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PCH680, PCH740 Service Manual

1. GENERAL TORQUE VALUES English Fastener Torque Recommendations for Standard Applications Bolts Screws Nuts and Fasteners Assembled Into Cast Iron or Steel Grade 2 or 5 Fasteners Into Aluminum Size Grade 2 Grade 5 Grade 8 Q Tightening Torque N m in Ib 20 8 32 2 3 20 2 8 25 2 3 20 10 24 3 6 32 4 5 40 3 6 32 10 32 3 6 32 4 5 40 1 4 20 7 9 70 13 0 115 18 7 165 7 9 70 1 4 28 9 6 85 15 8 140 22 6 200 5 16 18 17 0 150 28 3 250 39 6 350 17 0 150 5 16 24 18 7 165 30 5 270 3 8 16 29 4 260 3 8 24 33 9 300 Tightening Torque N m ft Ib 20 5 16 24 40 7 30 3 8 16 47 5 35 67 8 50 3 8 24 54 2 40 81 4 60 71 16 14 47 5 35 74 6 55 108 5 80 7 16 20 61 0 45 101 7 75 142 5 105 1 2 13 67 8 50 108 5 80 155 9 115 1 2 20 94 9 70 142 4 105 223 7 165 9 16 12 101 7 75 169 5 125 237 3 175 9 16 18 135 6 100 223 7 165 311 9 230 5 8 11 149 5 110 244 1 180 352 6 260 5 8 18 189 8 140 311 9 230 447 5 330 3 4 10 199 3 147 332 2 245 474 6 350 3 4 16 271 2 200 440 7 325 637 3 470 Metric Fastener Torque Recommendations for Standard Applications Property Class Noncritical Size ines Alaina Tightening Torque N m i
2. Speed Control Throttle Actuator A Bracket B Cable Clamp C Screw D Lever bottom E Spring Washer F Throttle D Lever G Flat Washer H Nut I Return Spring 1 Install governor lever onto governor cross shaft 2 Make sure throttle linkage linkage spring black linkage bushing are connected to governor lever and to throttle lever on throttle body Assemble Top Mount Control Panel 1 Install lower support control bracket with throttle control shaft 2 Install top mount control panel over throttle control shaft Secure control panel to blower housing with screws 3 Assemble throttle control lever and applicable hardware to throttle control shaft 4 Attach governor spring to previously marked hole on governor lever 24 690 32 Rev A KohlerEngines com 85 Reassembly Install Air Cleaner Assembly Install Oil Cooler Refer to Air Cleaner Intake for air cleaner reassembly procedure Heavy Duty Air Cleaner 1 Install air cleaner assembly onto throttle body mounting studs Secure and torque nuts to 7 4 9 0 N m 65 5 80 in Ib 2 Install and tighten two upper mounting screws securing air cleaner to mounting bracket Torque screws to 9 9 N m 88 in Ib Low Profile Air Cleaner 1 Verify O ring is present around machined O D of throttle body and place air cleaner base onto throttle body studs Secure air cleaner base using three nuts Attach air cleaner b
3. Remove Camshaft Q x sd R Piston Pin S Piston Rings T Crankcase U Governor Cross Shaft Remove camshaft Inspection and Service NOTE To prevent repeat failures camshaft and crankshaft should always be replaced as a set Check lobes of camshaft for wear or damage See Specifications for minimum lift tolerances Measurement must be performed while valve train is still assembled Inspect cam gear for badly worn chipped or missing teeth Replacement of camshaft will be necessary if any of these conditions exist Remove Governor Cross Shaft 1 Remove retainer and nylon washer from governor cross shaft 2 Remove cross shaft through inside of crankcase Governor Cross Shaft Oil Seal Cross Shaft Oil Seal Details A 2 0 mm 0 0787 in B Governor Cross Shaft Seal If governor cross shaft seal is damaged and or leaks replace it using these following procedures Remove oil seal from crankcase and replace it with a new one Install new seal to depth shown using a seal installer Remove Connecting Rods with Pistons and Rings NOTE If a carbon ridge is present at top of either cylinder bore use a ridge reamer tool to remove it before attempting to remove piston NOTE Cylinders are numbered on crankcase Use numbers to mark each end cap connecting rod and piston for reassembly Do not mix end caps and connecting rods 24 690 32 Rev A 1 Remove screws sec
4. Low system voltage Faulty injectors Faulty battery Loose or corroded connections Faulty spark plugs Lock off not functioning Fuel pressure low Insufficient fuel delivery TPS set incorrect ECU Reset and TPS Initialization Crankshaft position sensor loose or faulty TPS faulty Engine temp sensor faulty Faulty injectors Faulty spark plugs Insufficient fuel delivery TPS set incorrect TPS faulty Faulty engine temperature sensor Faulty injectors Fuel injector s fuel filter or fuel line Dirty air cleaner Insufficient fuel pressure or fuel delivery Vacuum intake air leak Improper governor setting adjustment or operation TPS faulty mounting problem or TPS Initialization Procedure incorrect Bad coil s spark plug s or wires 24 690 32 Rev A KohlerEngines com 37 Propane EFI System Troubleshooting Guide Condition Possible Cause Low Power Faulty malfunctioning ignition system Dirty air filter Insufficient fuel delivery or pressure Improper governor adjustment Plugged restricted exhaust One injector not working Basic engine problem exists TPS faulty or mounting exists Throttle plate in throttle body not fully opening to WOT stop if equipped Fault Codes Example of Diagnostic Display ZE 0 One second pause 1 One sec
5. KohlerEngines com 73 Reassembly Crankcase Components Closure Plate Seal Closure Plate Oil Pickup Tube Oil Pump Assembly Ball Governor Shaft Spring Governor Washer Oil Pump Cover O ring Governor Gear Outer Gerotor Gear Governor Cup o O AX a 4 ur T O I M Camshaft Crankshaft Connecting Rod Piston Q Pistan oo Piston Pin Piston Rings Crankcase U Governor Cross Shaft NOTE Make sure engine is assembled using all specified torque values tightening sequences and clearances Failure to observe specifications could cause severe engine wear or damage Always use new gaskets Apply a small amount of oil to threads of critical fasteners before assembly unless a Sealant or Loctite is specified or preapplied Make sure all traces of any cleaner are removed before engine is assembled and placed into operation Even small amounts of these cleaners can quickly break down lubricating properties of engine oil Check closure plate crankcase and cylinder heads to be certain that all old sealing material has been removed Use gasket remover lacquer thinner or paint remover to remove any remaining traces Clean surfaces with isopropyl alcohol acetone lacquer thinner or electrical contact cleaner 74 KohlerEngines com 24 690 32 Rev A Install Flywheel End Oil Seal Oil Seal Detail A 45mm 0 17
6. e Clogged broken or inoperative crankcase breather e Loose or improperly torqued fasteners e Piston blow by or leaky valves e Restricted exhaust 18 KohlerEngines com EXTERNAL ENGINE INSPECTION NOTE It is good practice to drain oil at a location away from workbench Be sure to allow ample time for complete drainage Before cleaning or disassembling engine make a thorough inspection of its external appearance and condition This inspection can give clues to what might be found inside engines and cause when it is disassembled e Check for buildup of dirt and debris on crankcase cooling fins grass screen and other external surfaces Dirt or debris on these areas can cause overheating Check for obvious fuel and oil leaks and damaged components Excessive oil leakage can indicate a clogged or inoperative breather worn or damaged seals or gaskets or loose fasteners Check air cleaner cover and base for damage or indications of improper fit and seal Check air cleaner element Look for holes tears cracked or damaged sealing surfaces or other damage that could allow unfiltered air into engine A dirty or clogged element could indicate insufficient or improper maintenance Check carburetor throat for dirt Dirt in throat is further indication that air cleaner was not functioning properly Check if oil level is within operating range on dipstick If itis above sniff for gasoline odor Check condition of oil Drai
7. NOTE If crankpin is reground visually check to ensure fillet blends smoothly with crankpin surface NOTE To prevent repeat failures camshaft and crankshaft should always be replaced as a set Inspect gear teeth of crankshaft If teeth are badly worn chipped or some are missing replacement of crankshaft will be necessary Inspect crankshaft bearing surfaces for scoring grooving etc Some engines have bearing inserts in crankshaft bore of closure plate and or crankcase Do not replace bearings unless they show signs of damage or are out of running clearance specifications If crankshaft turns easily and noiselessly and there is no evidence of scoring grooving etc on races or bearing surfaces bearings can be reused Inspect crankshaft keyways If they are worn or chipped replacement of crankshaft will be necessary Inspect crankpin for score marks or metallic pickup Slight score marks can be cleaned with crocus cloth soaked in oil If wear limits as stated in Specifications and Tolerances are exceeded it will be necessary to either replace crankshaft or regrind crankpin to 0 25 mm 0 010 in undersize If reground a 0 25 mm 0 010 in undersize connecting rod big end must then be used to achieve proper running clearance Measure crankpin for size taper and out of round Connecting rod journal can be ground one size under When grinding a crankshaft grinding stone deposits can get caught in oil passages whic
8. 2 Allow ample time for oil to drain from crankcase and oil filter 3 Remove mounting screw and oil fill tube 4 Remove and discard oil filter 24 690 32 Rev A Disassembly Inspection and Service Remove Oil Cooler 1 Use an 8 mm Allen wrench to remove oil filter threaded nipple 2 Separate filter adapter from closure plate leaving oil lines attached Remove screws mounting oil cooler to blower housing then remove cooler lines and filter adapter with O ring as an assembly Remove Muffler Remove exhaust system and attaching hardware from engine On engines equipped with a port liner remove it now Remove Air Cleaner Assembly Heavy Duty Air Cleaner 1 Remove nuts securing air cleaner to mounting studs 2 Remove screws securing air cleaner assembly to mounting bracket and remove air cleaner assembly Low Profile Air Cleaner Optional Loosen retaining knob and remove cover Remove wing nut from element cover 3 Remove element cover element and precleaner 4 Remove nuts securing base Additional screws must be removed from lower air cleaner support bracket 5 Remove base N gt Remove Control Panel Assembly If Equipped 1 Disconnect cables from throttle levers 2 Remove screws fastening control panel and remove panel from blower housing Remove External Governor Controls NOTE To aid in reassembly mark hole locations of governor spring throttle linkage spring throttle
9. Conclusion e Battery e Main system fuse e MIL light bulb burned out e MIL electrical circuit problem Pin circuits Grey 3 e gnition switch e Permanent ECU power circuit problem Pin circuit Black 18 e Switched ECU power circuit problem Pin circuit Black 15 e ECU grounds e ECU Diagnostic Aid 2 FAULT CODES Refer to Diagnostic Fault Code Summary Diagnostic Aid 3 RUN ON MIL remains ON while engine is running Condition NOTE Either incandescent or LED type bulbs can be used for MIL as long as they do not draw more than 0 1 amps Bulb needs to be rated at 1 4 Watts or less or needs to have a total resistance of 140 O or more LEDs typically draw less than 0 03 amps All current fault codes will turn on MIL when engine is running Diagnostic Aid 4 CRANKSHAFT POSITION SENSOR MIL does not turn off during cranking Condition e Crankshaft position sensor e Crankshaft position sensor circuit problem pin circuits Black 4 and Black 13 e Crankshaft position sensor toothed wheel air gap e Toothed wheel e Flywheel key sheared e ECU Diagnostic Aid 5 FUEL LOCK OFF lock off not activating Condition e Main fuse e Fuel lock off circuit problem pin circuits Black 9 and Grey 17 e Fuel lock off 24 690 32 Rev A Propane EFI System Diagnostic Aid 6 IGNITION SYSTEM no spark Condition e Spark plug e Plug wire e Coil e Coil circuit s pin circuits Grey 10 and Black 1 e ECU gro
10. KOHLER Command PRO PCH680 PCH740 Propane Electronic Fuel Injection EFI Service Manual IMPORTANT Read all safety precautions and instructions carefully before operating equipment Refer to operating instruction of equipment that this engine powers Ensure engine is stopped and level before performing any maintenance or service 2 Safety 3 Maintenance 5 Specifications 14 Tools and Aids 17 Troubleshooting 21 Air Cleaner Intake 22 Propane Electronic Fuel Injection EFI System 47 Lubrication System 49 Electrical System 54 Starter System 58 Disassembly Inspection and Service 74 Reassembly 24 690 32 Rev A KohlerEngines com Safety SAFETY PRECAUTIONS A WARNING A hazard that could result in death serious injury or substantial property damage A CAUTION A hazard that could result in minor personal injury or property damage NOTE is used to notify people of important installation operation or maintenance information A WARNING Explosive Fuel can cause fires and severe burns If a gaseous odor is GAL detected ventilate area and contact an authorized service technician 4 WARNING Carbon Monoxide can cause severe nausea fainting or death Avoid inhaling exhaust fumes A CAUTION Y Electri
11. reassembly install oil pressure adapter instead of oil filter Prefill a new oil filter following instructions Place new filter in shallow pan with open end up Fill with new oil until oil reaches bottom of threads Allow 2 minutes for oil to be absorbed by filter material Apply a thin film of clean oil to rubber gasket on oil filter Refer to instructions on oil filter for proper installation Fill crankcase with new oil Level should be at top of indicator on dipstick Reinstall oil fill cap dipstick and tighten securely Connect Spark Plug Leads 1 Connect leads to spark plugs 24 690 32 Rev A Prepare Engine for Operation Reassembly Testing Engine NOTE If ECU or TPS throttle body were replaced an ECU Reset and TPS Learn is required Refer to ECU Reset and TPS Learn procedures in Fuel System Engine is now completely reassembled Before starting or operating engine be sure to follow steps below 1 2 4 5 Make sure all hardware is tightened securely Make sure oil drain plugs Oil Sentry pressure Switch and a new oil filter are installed Fill crankcase with correct amount weight and type of oil Refer to oil recommendations and procedures in Maintenance Specifications and Lubrication System Adjust idle speed adjusting screw as necessary Refer to Fuel System Turn on fuel supply Sensitivity Adjustment Governor Lever B Hole 1 H
12. Do not allow battery cables to touch opposing terminals When connecting battery cables attach positive cable to positive battery terminal first sak by negative cable to negative battery terminal Never start engine when cables are loose or poorly connected to battery terminals Never disconnect battery while engine is running Never use a quick battery charger to start engine Do not charge battery with key switch ON Always disconnect negative battery cable before charging battery and also unplug harness from ECU before performing any welding on equipment 24 690 32 Rev A KohlerEngines com 25 Propane EFI System ELECTRICAL COMPONENTS Grey Connector Electronic Control Unit ECU Pin Description Pinout of ECU 1 Not Used Black Connector 2 Not Used Pin Function 3 Malfunction Indicator Light MIL Ground 1 ignition Coil 1 Ground 4 Not Used 2 Battery Ground 5 Not Used 3 Diagnostic Communication Line 6 Not Used 4 Speed Sensor input 7 Not Used 5 Fuel Injector Output 1 Ground 8 Not Used 6 Fuel Injector Output 2 Ground 9 Battery Ground 7 Oxygen Sensor Heater 10 Ignition Coil 2 Ground 8 Intake Air Temperature IAT sensor input 11 Not Used 9 Fuel Lock Off Ground 12 Not Used 10 Ground for IAT TPS MAP O2 and Oil Sensors 13 Not Used 11 Manifold
13. E Oil Fill F Back Side G Oil Cooler H Oil Filter OIL RECOMMENDATIONS 1 Remove dipstick wipe oil off Refer to Maintenance 2 Reinsert dipstick into tube press completely down CHECK OIL LEVEL 3 Remove dipstick check oil level Level should be at NOTE To prevent extensive engine wear or damage top of indicator on dipstick never run engine with oil level below or above 4 If oil is low on indicator add oil up to top of indicator operating range indicator on dipstick mark Ensure engine is cool Clean oil fill dipstick areas of any 5 Reinstall and secure dipstick debris 24 690 32 Rev A KohlerEngines com 47 Lubrication System CHANGE OIL AND FILTER Change oil while engine is warm 1 9 Clean area around oil fill cap dipstick and drain plug Remove drain plug and oil fill cap dipstick Allow oil to drain completely Clean area around oil filter Place a container under filter to catch any oil and remove filter Wipe off mounting surface Reinstall drain plug Torque to 13 6 N m 10 ft Ib Place new filter in shallow pan with open end up Fill with new oil until oil reaches bottom of threads Allow 2 minutes for oil to be absorbed by filter material Apply a thin film of clean oil to rubber gasket on new filter Refer to instructions on oil filter for proper installation Fill crankcase with new oil Level should be at top of indicator on dipstick Reinstall oil fill cap dipstick and tighten securely
14. G S jloyejnBay sezuode A apeg o esnJj voe d Joyeinbay seynooy o JojejS N yoejg W Kai 7 SUM M UEL f Xuld I ajdind H anig eq 5 U9AJEO Jeq E u 19 iur 3 MOJISA a SUUM PEY 9 xXoe g pes a poy V oo PE JE JE E EJP BE IE c Seay 0699960 606 p 66 99 66 69 66 k YN o o O o O o oO o o o o o O D Oo o Oo O O 5i 29 KohlerEngines com A X i NIN d Sv d om TC d b jeuonudo u 1iMs Avy 103128uuo euruuo G we1Berg BuuM 143 24 690 32 Rev A Propane EFI System Crankshaft Position Sensor A sealed non serviceable assembly If Fault Code diagnosis indicates a problem within this area test and correct as follows 1 Check mounting and air gap of sensor It must be 0 20 0 70 mm 0 008 0 027 in 2 Inspect wiring and connections for damage or problems 3 Make sure engine has resistor type spark plugs Disconnect Black connector from ECU 5 Connect an ohmmeter between 4 and 13 pin terminals A resistance value of 325 395 O at room temperature 20 C 68 F should be obtained If resistance is correct check mounting air gap flywheel teeth damage run out etc and flywheel key 6 Disconnect crankshaft position sensor connector from wiring harness Test resistance between terminals A reading of 325 395 O should again be obtained a If resistance is incorrect remove screw
15. Year Manufactured Code Factory Code Code Year 43 2013 44 2014 45 2015 GENERAL SPECIFICATIONS PCH680 PCH740 Bore 83 mm 3 27 in Stroke 69 mm 2 72 in Displacement 747 cc 45 6 cu in Oil Capacity refill 1 6 1 9 L 1 7 2 0 U S qt Maximum Angle of Operation 25 full oil level TORQUE SPECIFICATIONS PCH680 PCH740 Blower Housing Into cored aluminum hole or weld nut 6 2 N m 55 in Ib into new holes 4 0 N m 35 in Ib into used holes M6 10 7 N m 95 in Ib into new holes 7 3 N m 65 in Ib into used holes Into extruded hole in sheet metal M5 2 8 N m 25 in Ib into new holes 2 3 N m 20 in Ib into used holes M6 2 8 N m 25 in Ib into new holes 2 3 N m 20 in Ib into used holes Closure Plate Fastener 25 6 N m 227 in Ib Connecting Rod Cap Fastener torque in increments 13 6 N m 120 in Ib 3Values are in Metric units Values in parentheses are English equivalents Exceeding maximum angle of operation may cause engine damage from insufficient lubrication 5 Lubricate threads with engine oil prior to assembly Any and all horsepower hp references by Kohler are Certified Power Ratings and per SAE J1940 8 J1995 hp standards Details on Certified Power Ratings can be found at KohlerEngines com 24 690 32 Rev A KohlerEngines com 7 Specifications TORQUE SPECIFICATIONS PCH680 PCH740 Crankcase Breather Cover Fastener 11 7 3 m 100 in Ib into new h
16. pressure check for conditions in table below 4 Close pinch clamp before stopping engine Condition To test crankcase vacuum with vacuum pressure gauge 1 Remove dipstick or oil fill plug cap 2 Install adapter into oil fill dipstick tube opening upside down over end of a small diameter dipstick tube or directly into engine if a tube is not used Insert barbed gauge fitting into hole in stopper 3 Run engine and observe gauge reading Analog tester needle movement to left of 0 is a vacuum and movement to right indicates a pressure Digital tester depress test button on top of tester Crankcase vacuum should be a minimum of 10 2 cm 4 in of water If reading is below specification or if pressure is present check table below for possible causes and conclusions Conclusion Crankcase breather clogged or inoperative NOTE If breather is integral part of valve cover and cannot be serviced separately replace valve cover and recheck pressure Disassemble breather clean parts thoroughly check sealing surfaces for flatness reassemble and recheck pressure Seals and or gaskets leaking Loose or improperly torque fasteners Replace all worn or damaged seals and gaskets Make sure all fasteners are tightened securely Use appropriate torque valves and sequences when necessary Piston blow by or leaky valves confirm by inspecting components Restricted exhaust Recondition piston rings
17. 10 oil to prevent rusting Valve Stem Seal These engines use valve stem seals on intake and exhaust valves Always use a new seal when valves are removed from cylinder head Seals should also be replaced if deteriorated or damaged in any way Never reuse an old seal Flywheel Components A Flywheel Fan B Flywheel C Stator D Backing Plate NOTE Always use a flywheel strap wrench or holding tool to hold flywheel when loosening or tightening flywheel screw Do not use any type of bar or wedge to hold flywheel Use of such tools could cause flywheel to become cracked or damaged NOTE Always use a flywheel puller to remove flywheel from crankshaft Do not strike crankshaft or flywheel as these parts could become cracked or damaged Striking puller or crankshaft can cause crank gear to move affecting crankshaft endplay 66 KohlerEngines com 24 690 32 Rev A 1 Remove fan screws were removed earlier with debris screen 2 Use a flywheel strap wrench or holding tool see Tools and Aids to hold flywheel and loosen screw securing flywheel to crankshaft 3 Remove screw and washer 4 Use a puller to remove flywheel from crankshaft 5 Remove woodruff key Inspection Inspect flywheel for cracks and flywheel keyway for damage Replace flywheel if it is cracked Replace flywheel crankshaft and key if flywheel key is sheared or keyway is damaged Inspect ring gear for cracks or damage Kohler do
18. Absolute Pressure MAP sensor input 14 Safety Switch Ground 12 Throttle Position Sensor TPS input 15 Not Used 13 Speed Sensor Ground 16 ECU 14 Oil Temperature Sensor input 17 Fuel Lock Off Control 12V 15 Ignition Switch Switched 12V 18 Not Used 16 Power for TPS and MAP Sensors 5V 17 Oxygen Sensor O2 input 18 Battery Power Permanent 12V ECU BLACK CONNECTOR SIDE GREY CONNECTOR SIDE 123456789 w w m w w m m w w a 10 11 12 13 14 15 16 17 18 10 11 12 13 14 15 16 17 18 Pinout of ECU 26 KohlerEngines com 24 690 32 Rev A Never attempt to disassemble ECU It is sealed to prevent damage to internal components Warranty is void if case is opened or tampered with in any way All operating and control functions within ECU are preset No internal servicing or readjustment may be performed If a problem is encountered and you determine ECU to be faulty contact your source of supply ECU pins are coated at factory with a thin layer of electrical grease to prevent fretting and corrosion Do not attempt to remove grease from ECU pins Relationship between ECU and throttle position sensor TPS is very critical to proper system operation If TPS or ECU is changed or mounting position of TPS is altered appropriate TPS Learn Procedure must be performed to restore synchr
19. B Valve Cover O ring Hex Flange Screw D Rocker Arm Pivot E Rocker Arm F Push Rod Hydraulic Lifter H Valve Cap I Valve Keeper J Valve Spring Valve Seal L VM M Spark Plug N Cylinder Head e P Valve Q Dowel Pin NOTE Hydraulic lifters should always be installed in same position as before disassembly Exhaust lifters are located on output shaft closure plate side of engine while intake lifters are located on fan side of engine Cylinder numbers are embossed on top of crankcase and each cylinder head 1 See Servicing Hydraulic Lifters in Disassembly Inspection and Service Apply camshaft lubricant to bottom surface of each lifter Lubricate hydraulic lifters and lifter bores in crankcase with engine oil Note mark or tag identifying hydraulic lifters as either intake or exhaust and cylinder 1 or 2 Install hydraulic lifters into their appropriate locations in crankcase Do not use a magnet If breather reeds and stops were removed from crankcase reinstall them at this time and secure with screw Torque screw to 4 0 N m 35 in Ib 78 KohlerEngines com 24 690 32 Rev A Valve Stem Seals These engines use valve stem seals on intake valves and on exhaust valves Use a new seal whenever valve is removed or if seal is deteriorated or damaged in any way Never reuse an old seal Assemble Cylinder Heads Prior to installation lubricate all components with engine oil paying particular attention to lip of valve stem sea
20. Pin C and Pin D before engine is started With key ON and sensor unplugged voltage should read about 5 0 volts With sensor attached using diagnostic software voltage should read about 1 0 volt This voltage is generated by ECU If it is not present there is a short in associated wiring and corrective action should be taken If voltage still is not present there is a problem with ECU or engine harness Reconnect sensor and start engine Run engine at sufficient speed to bring sensor up to operating temperature Maintain for 1 to 2 minutes to ensure that engine has gone closed loop Once in closed loop sensor voltage should cycle between about 100 to 250 mv and 700 to 900 mv If this cycling is not observed a determination must be made if problem is with engine or sensor Check engine harness for battery voltage on heater circuit Removal Inspection NOTE Apply anti seize compound only to threads Anti seize compound will affect sensor performance if it gets into lower shield of sensor 1 If sensor has heavy deposits on lower shield engine oil or fuel may be source 2 f heavy carbon deposits are observed incorrect engine fuel control may be occurring 3 If sensor is at room temperature measure between signal leads black wire Pin C and grey wire Pin D attached to sensor If resistance is less than one megohm sensor has an internal short 4 With sensor at room temperature measure heater circuit resistance
21. Piston rings and cylinder in good condition Gauge reading in moderate yellow zone Engine is still usable but there is some wear present Customer should start planning for overhaul or replacement Gauge reading in high red zone Rings and or cylinder have considerable wear Engine should be reconditioned or replaced 20 KohlerEngines com 24 690 32 Rev A AIR CLEANER These systems are CARB EPA certified and components should not be altered or modified in any way Low Profile Air Cleaner Components A Air Cleaner Cover B Air Cleaner Knob C Wing Nut D Element Cover E Rubber Seal F Precleaner G Paper Element H Air Cleaner Base Heavy Duty Air Cleaner Components Air Cleaner Housing J End Cap K Element L Inner Element M Ejector Area N Inlet Screen o Retaining Clip P Filter Minder NOTE Operating engine with loose or damaged air cleaner components could cause premature wear and failure Replace all bent or damaged components NOTE Paper element cannot be blown out with compressed air 24 690 32 Rev A Air Cleaner Intake Low Profile Loosen knob and remove air cleaner cover Precleaner 1 Remove precleaner from paper element 2 Replace or wash precleaner in warm water with detergent Rinse and allow to air dry 3 Saturate precleaner with new engine oil squeeze out excess oil 4 Reinstall precleaner over paper element Pa
22. a useful technique for observing sensor performance However user must understand that such software reads a signal generated by ECU If there is an ECU or wiring problem readings could be misinterpreted as a sensor problem Digital nature of signal to software means that it is not reading continuous output of sensor A voltmeter can also be used as an effective tool in diagnosing sensors It is advisable to use an electronic meter such as a digital voltmeter Simple mechanical meters may place a heavy electrical load on sensor and cause inaccurate readings Since resistance of sensor is highest at low temperatures such meters will cause largest inaccuracies when sensor is in a cool exhaust Visual Inspection 1 Look for a damaged or disconnected sensor to engine harness connection 2 Look for damage to sensor lead wire or associated engine wiring due to cutting chaffing or melting on a hot surface 3 Disconnect sensor connector and look for corrosion in connector 4 Try reconnecting sensor and observe if problem has cleared 5 Correct any problems found during visual check KohlerEngines com 31 Propane EFI System Sensor Signal Observation NOTE Do not cut into or pierce sensor or engine 32 wiring to make this connection Sensor produces a very small signal Corrosion or damage to wiring could lead to an incorrect signal because of repairs or contamination to sensor Using a voltmeter observe voltage between
23. and snap clip together Install Fuel Injectors NOTE Ensure all parts are clean undamaged and free of debris and make sure electrical connectors have seal in place O rings and retaining clips should be replaced any time fuel injector is separated from its normal mounting position 1 Lightly lubricate fuel injector O rings with clean engine oil 2 Push retaining clip onto fuel injector aligning clip 3 Press fuel injector into fuel injector cap until retaining clip snaps into place 4 Press fuel injector into bore in intake manifold and rotate to original position 5 Install fuel injector cap screw into intake manifold and torque to 7 3 N m 65 in Ib 6 Push electrical connector on fuel injector making sure a good connection is made 7 Repeat steps 1 through 6 for other fuel injector 24 690 32 Rev A NOTE Ensure all parts are clean undamaged and free of debris and make sure electrical connector has seal in place 1 Lightly oil MAP sensor O ring and push MAP sensor into bore in intake manifold 2 Torque screw to 7 3 N m 65 in Ib 3 Push electrical connector on MAP sensor making sure a good connection is made Install Crankshaft Position Sensor NOTE Ensure all parts are clean undamaged and free of debris and make sure electrical connectors have seal in place 1 Install crankshaft position sensor and bracket assembly to crankcase posts 2 Snug screws and check air gap of sensor
24. appear as they may not be in numerical sequence b Code 61 will always be last code displayed indicating end of code transmission If code 61 appears immediately no other fault codes are present After problem has been corrected fault codes may be cleared by following ECU Reset and TPS Learn Procedures Diagnostic Fault Code Summary lists fault codes and what they correspond to Diagnostic Code Summary is a list of individual codes with an explanation of what triggers them what symptoms might be expected and probable causes 24 690 32 Rev A A MIL may not be provided with engine If equipment manufacturer has not added a MIL to equipment one can be added easily for quick diagnostics Main engine to vehicle connection will have a tan wire which is ground for MIL Either incandescent or LED type bulbs can be used for MIL as long as they do not draw more than 0 1 amps Bulb needs to be rated at 1 4 Watts or less or needs to have a total resistance of 140 O or more LEDs typically draw less than 0 03 amps Attach 12 volts to positive terminal of bulb and attach ground terminal of bulb to tan wire Diagnostic Code Summary Code 0031 Component Oxygen Sensor Heater Fault O2S Heater Circuit High Voltage Condition System voltage too high shorted connection or faulty sensor Conclusion Oxygen Sensor Related e Sensor connector or wiring problem e Sensor damaged e Pin circuit wiring
25. at high pressure fuel high pressure fuel line TPS malfunction line TPS malfunction shorted shorted connection faulty sensor low connection faulty sensor or regulator fuel or wrong fuel type failure Conclusion Oxygen Sensor Related Conclusion Oxygen Sensor Related e Corrosion or poor connection e Sensor connector or wiring e Sensor contaminated or damaged e Sensor contaminated or damaged e Air leak into exhaust e Poor ground path e Poor ground path e Pin circuit wiring or connectors e Pin circuit wiring or connectors ECU Black pin 10 or 17 ECU Black pin 10 or Black pin 17 TPS Sensor Related TPS Sensor Related e Throttle plate position incorrect during e Throttle plate position incorrect during Learn procedure Learn procedure e TPS problem or malfunction e TPS problem or malfunction Engine Wiring Harness Related Engine Wiring Harness Related e Difference in voltage between sensed e Difference in voltage between sensed voltage and actual sensor voltage voltage and actual sensor voltage e Problem in wiring harness e Problem in wiring harness e ECU to harness connection problem e ECU to harness connection problem Systems Related Systems Related e Ignition spark plug plug wire ignition e Ignition spark plug plug wire ignition coil coil e Fuel fuel type quality injector fuel e Fuel fuel type quality injector fuel pressure too high fuel regulator pressure too low fuel lock off or e Combustion air air
26. aus 21 0 EGULATOR ASSEMBLY Se if MOUNTING OIL DRAIN PLUG 3 8 NPT TSK 97 0 X90 15K 612 0 X90 TSK 0 13 5X 90 WEN MOUNTING HOLE A ENGINE MOUNTING SURFACE PILOT 146 05 5 750 OIL FILTER SIDE l PTO SIDE Specifications Engine Dimensions with Low Profile Air Cleaner Dimensions in millimeters Inch equivalents shown in na 5990358 VANECVER 2851 AIR CLEANER SPARK PLUG COVER REMOVAL REMOVAL 353 02 VALVE COVER 113 898 115 90 14 563 ay 70 21 isis 12764 na Kam 3000 1181 2869 em SPARK PLUG SPARK PLUG REMOVAL DIPSTICK OIL FILL 1151 ISPARK PLUG 47301 W 18 622 DES 319 12 SPARK PLUG 12 564 i SPARK PLUG 113 15 32038 REMOVAL REMOVAL HIH
27. cleaner dirty regulator restricted e Combustion air air cleaner dirty e Base engine problem rings valves restricted intake leak throttle bores e Base engine problem rings valves e Exhaust system leak muffler flange oxygen sensor mounting boss etc 42 KohlerEngines com 24 690 32 Rev A Propane EFI System Code 0174 Code 0202 Component Fuel System Component Fuel Injector Fault Lean fuel condition Fault Injector 2 Circuit Malfunction Condition Fuel filters plugged low pressure at high Condition Injector damaged or faulty shorted or pressure fuel line TPS malfunction open connection shorted connection or faulty sensor Conclusion Injector Related Conclusion TPS Learn Incorrect e Injector coil shorted or opened e Lean condition check oxygen sensor signal with VOA and see Oxygen Engine Wiring Harness Related Sensor e Broken or shorted wire in harness ECU pin Black 6 Engine Wiring Harness Related e Wiring from Ignition e Pin circuit wiring or connectors ECU pin Black 10 12 16 and 17 ECU Related e Circuit controlling injector 2 damaged Low Fuel Pressure e Low empty fuel tank Code 0230 e Plugged filters Component Fuel Lock off e Bad regulator Fault Circuit Low Voltage or Open Oxygen Sensor Related Condition Shorted or open connection e Sensor connector or wiring problem Conclusion Fuel Lock off Re
28. considered For example a starting problem could be caused by an empty fuel tank Some general common causes of engine troubles are listed below and vary by engine specification Use these to locate causing factors Engine Cranks But Will Not Start Engine Will Not Crank e Battery connected backwards e Blown fuse e Carburetor solenoid malfunction e Choke not closing e Clogged fuel line or fuel filter e Diode in wiring harness failed in open circuit mode e DSAI or DSAM malfunction e Empty fuel tank e Faulty electronic control unit e Faulty ignition coil s e Faulty spark plug s e Fuel pump malfunction vacuum hose clogged or leaking e Fuel shut off valve closed e gnition module s faulty or improperly gapped e Insufficient voltage to electronic control unit e Interlock switch is engaged or faulty e Key switch or kill switch in OFF position e Low oil level e Quality of fuel dirt water stale mixture e SMART SPARK malfunction e Spark plug lead S disconnected Engine Starts But Does Not Keep Running e Battery is discharged e Faulty electric starter or solenoid e Faulty key switch or ignition switch e Interlock switch is engaged or faulty e Loose wires or connections that intermittently ground ignition kill circuit e Pawls not engaging in drive cup e Seized internal engine components Engine Runs But Misses e Carburetor adjusted incorrectly e Engine overhe
29. contact with wall Scoring of cylinder wall can also be caused by localized hot spots resulting from blocked cooling fins or from inadequate or contaminated lubrication If cylinder bore is badly scored excessively worn tapered or out of round resizing is necessary Use an inside micrometer to determine amount of wear refer to Specifications then select nearest suitable oversize of either 0 25 mm 0 010 in or 0 50 mm 0 020 in Resizing to one of these oversizes will allow usage of available oversize piston and ring assemblies First resize using a boring bar then use these following procedures for honing cylinder 72 KohlerEngines com Honing Detail A 23 33 Crosshatch NOTE Kohler pistons are custom machined to exacting tolerances When oversizing a cylinder it should be machined exactly 0 25 mm 0 010 in or 0 50 mm 0 020 in over new diameter Specifications Corresponding oversize Kohler replacement piston will then fit correctly While most commercially available cylinder hones can be used with either portable drills or drill presses use of a low speed drill press is preferred as it facilitates more accurate alignment of bore in relation to crankshaft crossbore Honing is best accomplished at a drill speed of about 250 RPM and 60 strokes per minute After installing coarse stones in hone proceed as follows 1 Lower hone into bore and after centering adjust so stones are in contac
30. corrected to ignition coil and ECU power switch must be turned OFF for 10 seconds for injector signal to return This is a safety measure to prevent bore washing and oil dilution Testing Using an ohmmeter set on Rx1 scale check resistance in circuits as follows 1 To check cylinder coil 1 starter side disconnect Black connector from ECU and test between Black pins 1 and 15 To check cylinder coil 2 oil filter side disconnect Grey connector from ECU and test between Grey pins 10 and 17 Wiring and coil primary circuits are OK if readings are 0 5 0 8 O 2 If reading s are not within specified range check and clean connections and retest 3 Ifreading s are still not within specified range test coils separately from main harness as follows a Remove screw retaining coil to housing and disconnect primary leads connector b Connect an ohmmeter set on Rx1 scale to primary terminals of coil Primary resistance should be 0 5 0 8 O c Connect an ohmmeter set on Rx10K scale between spark plug boot terminal and B primary terminal Secondary resistance should be 6400 7800 O d If secondary resistance is not within specified range coil is faulty and needs to be replaced 24 690 32 Rev A Propane EFI System FUEL COMPONENTS A Fluid puncture injuries are highly toxic and hazardous If an injury occurs seek immediate medical attention A WARNING High Pressure Fluids can puncture skin and cause sever
31. faulty sensor or faulty sensor grounding sensor Conclusion Crankshaft Position Sensor Related Conclusion Engine Wiring Harness Related e Sensor connector or wiring e Connection to ignition or fuse e Sensor loose or air gap incorrect e Pin circuit wiring or connectors e ECU pin Black 1 Crankshaft Position Sensor Wheel e ECU to harness connection problem Related e Damaged teeth Ignition System Related e Gap section not registering e Incorrect spark plug s used e Poor connection to spark plug Engine Wiring Harness Related Code 0352 e Pin circuit wiring or connectors ECU pin Black 4 and Black 13 Component Ignition Coil e ECU to harness connection problem Fault Cylinder 2 Ignition Coil Malfunction lanition System Related Condition Broken wire in harness may not be amen my Stent Slate visible shorted connection or faulty e Non resistor spark plug s used sensor e Faulty or disconnected ignition coil or CETTE secondary lead Conclusion Engine Wiring Harness Related e Connection to ignition or fuse e Pin circuit wiring or connectors Code 0337 ECU pin Grey 10 Component Crankshaft Position Sensor e ECU to harness connection problem Fault Crankshaft Position Sensor No Signal am ae Condition Air gap incorrect loose sensor open or ipsios dok Aera shorted connection or faulty sensor epu POLE ULLUS Conclusion Crankshaft Position Sensor Related e Sensor connector or wiring e Sensor loose or air gap
32. incorrect Code 0562 ES Component System Voltage SC Position Sensor Wheel Fault System Voltage Low e Damaged teeth Condition Faulty voltage regulator bad fuse or shorted connection Engine Wiring Harness Related Conclusion Corroded Connections e Pin circuit wiring or connectors ECU pin Black 4 or Black 13 Bad Stator e ECU to harness connection problem Bad Battery If code is stored in fault history and starts e Low output charging system normally Clear code no other service e Poor magnet in flywheel required e Bad or missing fuse Code 0563 Component System Voltage Fault System Voltage High Condition Faulty voltage regulator or shorted connection Conclusion Faulty Rectifier Regulator Bad Stator Bad Battery Code 61 Component End of Code Transmission 44 KohlerEngines com 24 690 32 Rev A Troubleshooting Flow Chart Following flow chart provides an alternative method of troubleshooting EFI system Chart will enable you to review entire system in about 10 15 minutes Using chart accompanying diagnostic aids listed chart and any signaled fault codes you should be able to quickly locate any problems within system Flow Chart Diagnostic Aids Diagnostic Aid 1 SYSTEM POWER MIL does not illuminate when key is turned ON NOTE MIL is installed by vehicle OEM Twelve volt supply to bulb will be part of vehicle wire harness Kohler key switch model will have MIL on engine with 12V supply to bulb
33. intake valve opens air fuel mixture is drawn into combustion chamber compressed ignited and burned ECU controls amount of fuel being injected and ignition timing by monitoring primary sensor signals for engine temperature speed RPM and throttle position load These primary signals are compared to preprogrammed maps in ECU computer chip and ECU adjusts fuel delivery to match mapped values After engine reaches operating temperature an exhaust gas oxygen sensor provides feedback to ECU based upon amount of unused oxygen in exhaust indicating whether fuel mixture being delivered is rich or lean Based upon this feedback ECU further adjusts fuel input to re establish ideal air fuel ratio This operating mode is referred to as closed loop operation EFI system operates closed loop when all three of following conditions are met e Oil temperature is greater than 60 C 140 F e Oxygen sensor has warmed sufficiently to provide a signal minimum 400 C 752 F e Engine operation is at a steady state not starting warming up accelerating etc During closed loop operation ECU has ability to readjust temporary and learned adaptive controls providing compensation for changes in overall engine condition and operating environment so it will be able to maintain ideal air fuel ratio This system requires a minimum engine oil temperature greater than 80 C 176 F to properly adapt These adaptive values are maintained as long a
34. is 7 6 mm 0 300 in Replace brushes if they are worn undersize or condition is questionable KohlerEngines com 55 Starter System Armature Components and Details A B A Commutator O D B Mica Insulation C Insulation Check D Armature Coil E Continuity Check 1 Clean and inspect commutator outer surface Mica insulation must be lower than commutator bars undercut to ensure proper operation of commutator 2 Use an ohmmeter set to Rx1 scale Touch probes between 2 different segments of commutator and check for continuity Test all segments Continuity must exist between all or armature is bad 3 Check for continuity between armature coil segments and commutator segments There should be no continuity If continuity exists between any 2 armature is bad 4 Check armature windings insulation for shorting Shift Fork Check that shift fork is complete and pivot and contact areas are not excessively worn cracked or broken Brush Replacement 4 brushes and springs are serviced as a set Use a new Kohler brush and spring kit if replacement is necessary 1 2 56 Perform steps 1 5 in Starter Disassembly Remove screws securing brush holder assembly to end cap plate Note orientation for reassembly later Discard old brush holder assembly Clean component parts as required New brushes and springs come preassembled in a brush holder with a prote
35. linkage before removing them from governor lever 1 Disconnect governor spring attached to governor lever Note mark hole location for reassembly 2 Note mark hole location then disconnect throttle linkage spring from governor lever Remove throttle linkage bushing and throttle linkage from governor lever Note mark hole location for reassembly 3 Lonen nut and remove governor lever from cross shaft KohlerEngines com 59 Disassembly Inspection and Service External Governor Controls top Speed Control Throttle Actuator i Bracket B Cable Clamp E S05 Lever bottom E Spring Washer F Throttle Control Lever G Flat Washer Nut Return Spring Vaporizer Regulator Lock Off Assembly W Explosive Fuel can cause fires and severe burns If a gaseous odor is detected ventilate area and contact an authorized service technician A WARNING leaks Propane is extremely flammable and is heavier than air and tends to settle in low areas where a spark or flame could ignite gas Do not start or operate this engine in a poorly ventilated area where leaking gas could accumulate and endanger safety of persons in area To ensure personal safety installation and repair of propane fuel supply systems must be performed only by qualified propane system technicians Improperly installed and maintained propane equ
36. m 55 in Ib CLEARANCE SPECIFICATIONS n had Camshaft End Play with shim 0 101 0 406 mm 0 0040 0 0160 in Running Clearance 0 025 0 105 mm 0 001 0 004 in Bore I D New 20 000 20 025 mm 0 7874 0 7884 in Max Wear Limit 20 038 mm 0 7889 in Bearing Surface O D New 19 920 19 975 mm 0 7843 0 7864 in Max Wear Limit 19 914 mm 0 7840 in 3Values are in Metric units Values in parentheses are English equivalents 5 Lubricate threads with engine oil prior to assembly 24 690 32 Rev A KohlerEngines com 9 Specifications CLEARANCE SPECIFICATIONS Connecting Rod PCH680 PCH740 Connecting Rod to Crankpin Running Clearance 21 C 70 F New Max Wear Limit 0 043 0 073 mm 0 0017 0 0029 in 0 088 mm 0 0035 in Connecting Rod to Crankpin Side Clearance 0 26 0 63 mm 0 0102 0 0248 in Connecting Rod to Piston Pin Running Clearance 21 C 70 F Piston Pin End LD 21 C 70 F New Max Wear Limit 0 015 0 028 mm 0 0006 0 0011 in 17 015 17 023 mm 0 6699 0 6702 in 17 036 mm 0 6707 in Crankcase New Max Wear Limit Governor Cross Shaft Bore D 8 025 8 075 mm 0 3159 0 3179 in 8 088 mm 0 3184 in Crankshaft End Play free Bore in crankcase New Max Wear Limit 0 025 0 635 mm 0 001 0 025 in 40 972 40 997 mm 1 6131 1 6141 in 41 011 mm 1 6146 in Bore in closure plate New 40 974 41 000 mm 1 6
37. mm 0 0598 0 0708 in Used Bore Max 2 051 mm 0 08068 in Values are in Metric units Values in parentheses are English equivalents 24 690 32 Rev A KohlerEngines com 11 Specifications CLEARANCE SPECIFICATIONS PCH680 PCH740 Piston Piston Rings and Piston Pin continued Thrust Face O D 82 978 mm 3 2668 in Max Wear Limit 82 833 mm 3 2611 in Piston Thrust Face to Cylinder Bore Running Clearance New 0 019 0 062 mm 0 0007 0 0024 in Valves and Valve Lifters Hydraulic Lifter to Crankcase 0 011 0 048 mm 0 0004 0 0019 in Running Clearance Intake Valve Stem to Valve 0 040 0 078 mm 0 0016 0 0031 in Guide Running Clearance Exhaust Valve Stem to Valve 0 052 0 090 mm 0 0020 0 0035 in Guide Running Clearance Intake Valve Guide I D New 7 040 7 060 mm 0 2772 0 2780 in Max Wear Limit 7 134 mm 0 2809 in Exhaust Valve Guide I D New 7 040 7 060 mm 0 2772 0 2780 in Max Wear Limit 7 159 mm 0 2819 in Valve Guide Reamer Size Standard 7 050 mm 0 2776 in 0 25 mm O S 7 300 mm 0 2874 in Intake Valve Minimum Lift 8 07 mm 0 3177 in Exhaust Valve Minimum Lift 8 07 mm 0 3177 in Nominal Valve Seat Angle 45 3Values are in Metric units Values in parentheses are English equivalents 7 Measure 6 mm 0 236 in above bottom of piston skirt at right angles to piston pin 12 KohlerEngines com 24 690 32 Rev A Specifications
38. of injector prevent external fuel leakage and also insulate it from heat and vibration A special clip connects each injector to high pressure fuel line and holds it in place O rings and retaining clip must be replaced any time fuel injector is separated from its normal mounting position When key switch is on lock off valve will open briefly and allow fuel into system at 24 26 psi and voltage is present at injector At proper instant ECU completes ground circuit energizing injector Valve needle in injector is opened electromagnetically and pressure in high pressure fuel line forces fuel down through inside Director plate at tip of injector contains a series of calibrated openings which directs fuel into manifold Injectors have sequential fueling that open and close once every other crankshaft revolution Amount of fuel injected is controlled by ECU and determined by length of time valve needle is held open also referred to as injection duration or pulse width Time injector is open milliseconds may vary in duration depending on speed and load requirements of engine A high voltage solid state battery ignition system is used with EFI system ECU controls ignition output and timing through transistorized control of primary current delivered to coils Based on input from crankshaft position sensor ECU determines correct firing point for speed at which engine is running At proper instant 24 KohlerEngines com it interrupts
39. on tip are an indication of general condition of piston rings valves and fuel system Normal and fouled plugs are shown in following photos Normal Plug taken from an engine operating under normal conditions will have light tan or gray colored deposits If center electrode is not worn plug can be set to proper gap and reused Worn On a worn plug center electrode will be rounded and gap will be greater than specified gap Replace a worn spark plug immediately Wet Fouled A wet plug is caused by excess fuel or oil in combustion chamber Excess fuel could be caused by a restricted air cleaner a fuel system problem or operating engine with too much choke Oil in combustion chamber is usually caused by a restricted air cleaner a breather problem worn piston rings or valve guides KohlerEngines com 49 Electrical System Carbon Fouled Soft sooty black deposits indicate incomplete combustion caused by a restricted air cleaner over rich settings weak ignition or poor compression Overheated Chalky white deposits indicate very high combustion temperatures This condition is usually accompanied by excessive gap erosion Lean settings an intake air leak or incorrect spark timing are normal causes for high combustion temperatures BATTERY A 12 volt battery with 400 cold cranking amps cca is generally recommended for starting in al
40. or unevenly worn Transmission Make sure clutch or transmission is disengaged or placed or in neutral This is especially important on eguipment with Engine hydrostatic drive Transmission must be exactly in neutral to prevent resistance which could keep engine from starting Check for seized engine components such as bearings connecting rod and piston 54 KohlerEngines com 24 690 32 Rev A SOLENOID SHIFT ELECTRIC STARTERS Solenoid Shift Starter Components A Tube B Washer C Armature D Drive E Stop F Retaining Ring G Collar H Drive End Cap l Screw J Plunger K Spring L Lever M Plate N Plug o Solenoid P Frame and Field Q Brush Holder R Nut S Commutator End T Screw Plate U Bolt When power is applied to starter armature rotates As armature rotates drive pinion moves out on drive shaft splines and into mesh with flywheel ring gear When pinion reaches end of drive shaft it rotates flywheel and cranks engine When engine starts flywheel rotates faster than starter armature and drive pinion This moves drive pinion out of mesh with ring gear and into retracted position When power is removed from starter armature stops rotating and drive pinion is held in retracted position by anti drift spring 24 690 32 Rev A Starter System Starter Disassembly NOTE Do not reuse old retainer NOTE Do not soak armature or use solvent when cleaning Wipe clean using a
41. purple wire Pin A and white wire Pin B resistance should be 8 1 11 1 O 5 If a damaged sensor is found identify root cause which may be elsewhere in application Refer to Troubleshooting Oxygen Sensor O table 6 Aspecial dry to touch anti seize compound is applied to all new oxygen sensors at factory If recommended mounting thread sizes are used this material provides excellent anti seize capabilities and no additional anti seize is needed If sensor is removed from engine and reinstalled anti seize compound should be reapplied Use an oxygen sensor safe type anti seize compound It should be applied according to directions on label KohlerEngines com 24 690 32 Rev A Troublshooting Oxygen Sensor O Propane EFI System Condition Possible Cause Conclusion Low voltage output Shorted sensor or sensor circuit Shorted lead wire Wiring shorted to ground Replace sensor or repair wiring Contamination of air reference Remove source of external contamination protect air reference area Air leak at sensor or gasket sensor upper shield damage Use recommended torque at installation replace gasket or sensor Revise application exhaust Shield sensor from damage High voltage output Silica poisoning Replace sensor Contaminated fuel Use high quality fuel Engine problem misfire Correct cause of misfire Excessive rich air fuel ratio Check fo
42. ring groove and roll O ring over tool onto fuel injector Torque screw securing fuel injector caps and blower housing mounting screws to 7 3 N m 65 in Ib and intake manifold and air cleaner mounting screws to 10 5 N m 93 in Ib An ECU Reset will need to be completed 24 690 32 Rev A Injector problems due to dirt or clogging are generally unlikely due to design of injectors and high fuel pressure Symptoms that could be caused by dirty clogged injectors include rough idle hesitation stumbling during acceleration or triggering of fault codes related to fuel delivery Injector clogging is usually caused by a buildup of deposits inside injector or on inlet filter restricting flow of fuel resulting in low flow Some contributing factors to injector clogging include higher than normal operating temperatures short operating intervals and dirty incorrect or poor quality fuel Cleaning of clogged injectors is not recommended they should be replaced Ignition Coil If a coil is determined to be faulty replacement is necessary An ohmmeter may be used to test wiring and coil windings NOTE Do not ground primary coil with ignition ON as they may overheat or spark NOTE Always disconnect spark plug lead from spark plug before performing following tests NOTE If ignition coil s are disabled and an ignition fault is registered system will automatically disable corresponding fuel injector drive signal Fault must be
43. sensor is used by system to help determine fuel requirements for starting a cold engine needs more fuel than one at or near operating temperature Mounted in breather cover it has a temperature sensitive resistor that extends into oil flow Resistance changes with oil temperature altering voltage sent to ECU Using a table stored in its memory ECU correlates voltage drop to a specific temperature Using fuel delivery maps ECU then knows how much fuel is required for starting at that temperature Intake Air Temperature IAT sensor is a thermally sensitive resistor that exhibits a change in electrical resistance with a change in its temperature When sensor is cold resistance of sensor is high As sensor warms up resistance drops and voltage signal increases From voltage signal ECU can determine temperature of intake air Purpose of an air temperature sensor is to help ECU calculate air density Higher air temperature less dense air becomes As air becomes less dense ECU knows that it needs to lessen fuel flow to achieve correct air fuel ratio If fuel ratio was not changed engine would become rich possibly losing power and consuming more fuel KohlerEngines com 23 Propane EFI System Oxygen sensor functions like a small battery generating a voltage signal to ECU based upon difference in oxygen content between exhaust gas and ambient air Tip of sensor protruding into exhaust gas is hollow Outer portion of tip is s
44. soft cloth or use compressed air 1 Remove nut and disconnect positive brush lead bracket from solenoid terminal 2 Remove screws securing solenoid to starter 3 Remove retaining ring from armature shaft using either a retaining ring pliers or snap ring removal tool as described in Steps 4 and 5 Do not reuse old retainer 4 Remove thru larger bolts 5 Remove commutator end plate assembly containing brush holder brushes springs and locking caps Remove thrust washer from inside commutator end 6 Remove frame from armature and drive end cap 7 Remove rubber grommet and backing plate from end cap 8 Take out drive lever and pull armature out of drive end cap 9 Remove thrust washer from armature shaft 10 Push stop collar down to expose retaining ring 11 Remove retainer from armature shaft Save stop collar 12 Remove drive pinion assembly from armature 13 Clean parts as required Inspection Check drive pinion and inspect following areas e Pinion teeth for abnormal wear or damage e Surface between pinion and clutch mechanism for nicks or irregularities which could cause seal damage e Check drive clutch by holding clutch housing and rotating pinion Pinion should rotate in only 1 direction Brushes and Springs Detail A Wear Limit Length Inspect both springs and brushes for wear fatigue or damage Measure length of each brush Minimum length for each brush
45. under this condition Oil control is also lost when ring gaps are not staggered during installation When cylinder temperatures get too high lacquer and KohlerEngines com 69 Disassembly Inspection and Service varnish collect on pistons causing rings to stick which results in rapid wear A worn ring usually takes on a shiny or bright appearance Scratches on rings and pistons are caused by abrasive material such as carbon dirt or pieces of hard metal Detonation damage occurs when a portion of fuel charge ignites spontaneously from heat and pressure shortly after ignition This creates 2 flame fronts which meet and explode to create extreme hammering pressures on a specific area of piston Detonation generally occurs from using low octane fuels Preignition or ignition of fuel charge before timed spark can cause damage similar to detonation Preignition damage is often more severe than detonation damage Preignition is caused by a hot spot in combustion chamber from sources such as glowing carbon deposits blocked cooling fins an improperly seated valve or wrong spark plug s Replacement pistons are available in STD bore size and in 0 25 mm 0 010 in and 0 50 mm 0 020 in oversize Replacement pistons include new piston ring sets and new piston pins Replacement ring sets are also available separately for STD 0 25 mm 0 010 in and 0 50 mm 0 020 in oversize pistons Always use new piston rings when installing
46. up 5 Install cylinder head Match numbers on cylinder heads and crankcase Make sure head is flat on gasket and dowel pins 6 Lightly lubricate exposed upper threads of studs with engine oil Install a flat washer and nut onto each of mounting studs Torque nuts in 2 stages first to 16 9 N m 150 in Ib then finally to 33 9 N m 300 in Ib following sequence Install Push Rods and Rocker Arms NOTE Push rods should always be installed in same position as before disassembly 1 Note mark or tag identifying push rod as either intake or exhaust and cylinder 1 or 2 Dip ends of push rods in engine oil and install making sure that each push rod ball seats in its hydraulic lifter socket 2 Apply grease to contact surfaces of rocker arms and rocker arm pivots Install rocker arms and rocker arm pivots on one cylinder head and start screws 3 Torque screws to 11 9 N m 105 in Ib 4 Use a spanner wrench or rocker arm lifting tool to lift rocker arms and position push rods underneath 5 Repeat above steps for remaining cylinder Do not interchange parts from cylinder heads 6 Rotate crankshaft to check for free operation of valve train Check clearance between valve spring coils at full lift Minimum allowable clearance is 0 25 mm 0 010 in Check Assembly Important Rotate crankshaft a minimum of 2 revolutions to check longblock assembly and overall proper operation Install Spark Plugs 1 Check
47. use precautions and procedures when installing flywheel RTV sealant is used as a gasket between closure plate and crankcase Always use fresh sealant Using outdated sealant can result in leakage 76 KohlerEngines com 24 690 32 Rev A Reassembly Flywheel Components A Flywheel Fan B Flywheel C Stator D Backing Plate NOTE Before installing flywheel make sure crankshaft Install Fan taper and flywheel hub are clean dry and completely free of any lubricants Presence of NOTE Position locating tabs on back of fan into locating lubricants can cause flywheel to be over holes of flywheel stressed and damaged when screw is torqued to 4 Install fan onto flywheelusing screws Steen 2 Torque screws to 9 9 N m 88 in Ib NOTE Make sure flywheel key is installed properly in E keyway Flywheel can become cracked or damaged if key is not properly installed 1 Install woodruff key into keyway of crankshaft Make sure that key is properly seated and parallel with shaft taper Install flywheel onto crankshaft being careful not to shift woodruff key 3 Install screw and washer Use a flywheel strap wrench or holding tool to hold flywheel Torque screw securing flywheel to crankshaft to 71 6 N m 52 8 ft Ib 24 690 32 Rev A KohlerEngines com T Reassembly Cylinder Head Components Install Hydraulic Lifters A Valve Cover
48. with a feeler gauge It must be 0 20 0 70 mm 0 008 0 027 in 3 Torque bracket screws to crankcase to 4 0 N m 35 in Ib into used holes or 6 2 N m 55 in Ib into new holes 4 Push electrical connector on crankshaft position sensor making sure a good connection is made Install Valve Covers Torque Sequence 1 Make sure sealing surfaces are clean 2 Make sure there are no nicks or burrs on sealing surfaces 3 Install a new O ring in groove of each cover 4 Position covers on cylinder heads Locate cover with oil separator hole on cylinder 1 Install screws in each cover and finger tighten 5 Torque valve cover fasteners to 6 2 N m 55 in Ib KohlerEngines com 81 Reassembly Install Breather Cover and Inner Baffles Torque Sequence Be sure sealing surfaces of crankcase and breather cover are clean of old gasket material Do not scrape surfaces as this could result in leakage Use a new gasket when installing breather cover Check to make sure there are no nicks or burrs on sealing surfaces Position breather gasket and cover on crankcase Install screws in locations 3 and 4 Finger tighten at this time Install inner baffles using remaining screws and finger tighten Do not torque screws at this time they will be tightened after blower housing Install Oil Temperature Sensor NOTE Ensure part is clean undamaged and free of debris and make sure e
49. 0 RPM and B at terminal on rectifier regulator to ground using a DC voltmeter If voltage is 13 8 volts or more place a minimum load of 5 amps turn on lights if 60 watts or more or place a 2 5 ohm 100 watt resistor across battery terminals on battery to reduce voltage Observe ammeter Conclusion Charging system is OK and battery was fully charged Test stator and rectifier regulator steps 2 and 3 Condition Charge rate increases when load is applied Charge rate does not increase when load is applied 2 Remove connector from rectifier regulator With engine running at 3600 RPM measure AC voltage across stator leads using an AC voltmeter Condition Conclusion Voltage is 28 volts or Stator is OK Rectifier more regulator is faulty replace Voltage is less than 28 Stator is faulty replace volts Test stator further using an ohmmeter steps 3 and 4 3 With engine stopped measure resistance across stator leads using an ohmmeter 52 Condition Conclusion Resistance is 0 064 0 2 ohms Stator is OK Resistance is 0 ohms Resistance is infinity ohms Stator is shorted replace Stator is open replace 4 With engine stopped measure resistance from each stator lead to ground using an ohmmeter Condition Conclusion Resistance is infinity ohms no continuity Stator is OK not shorted to ground Resistance
50. 1 and 16 Code 0117 Bad TPS Learn Component Coolant Oil Sensor Fault Coolant Oil Temperature Sensor Circuit Low Voltage Code 0108 Condition Shorted connection faulty sensor or Component Manifold Absolute Pressure Sensor shorted wire Fault MAP Circuit High Voltage Conclusion Temperature Sensor Related Condition Intake manifold leak shorted connection e Sensor wiring or connection or faulty sensor T Engine Wiring Harness Related Conclusion MAP Sensor Related e Pin circuits Black 10 and Black 14 See ie fai maybe damaged or routed near noisy e Vacuum leaks from loose manifold or signal coils stator etc sensor e ECU to harness connection problem Wire Harness Related e Poor grounding vede 0119 e Pin circuit wiring or connectors at Black Component Coolant Oil Sensor 11 Fault Coolant Oil Temperature Sensor Circuit Bad TPS L High Voltage or Open a gam Condition Shorted connection faulty sensor open connection or broken wire Code 0112 Conclusion Temperature Sensor Related Component Intake Air Temperature Sensor e Sensor wiring or connection Fault Intake Air Temperature Sensor Circuit Low Voltage Engine Wiring Harness Related Condition Shorted connection faulty sensor or e Pin circuits ECU Black pin 10 and 14 shorted wire may be damaged e ECU to harness connection problem or Conclusion Temperature Sensor Related broken wire e Sensor wiring or connection System Related Engin
51. 131 1 6141 in Crankshaft to Sleeve Bearing closure plate Running Clearance New Crankshaft Bore closure plate to Crankshaft Running Clearance New 0 03 0 12 mm 0 001 0 005 in 0 039 0 087 mm 0 0015 0 0034 in Flywheel End Main Bearing Journal O D New O D Max Wear Limit Max Taper Limit Max Out of Round Limit Closure Plate End Main Bearing Journal O D New O D Max Wear Limit Max Taper Limit Max Out of Round Limit Connecting Rod Journal O D New O D Max Wear Limit Max Taper Limit Max Out of Round Limit Crankshaft T I R PTO End Crank in Engine Entire Crank in V Blocks 40 913 40 935 mm 1 6107 1 6116 in 40 843 mm 1 608 in 0 022 mm 0 0009 in 0 025 mm 0 0010 in 40 913 40 935 mm 1 6107 1 6116 in 40 843 mm 1 608 in 0 022 mm 0 0009 in 0 025 mm 0 0010 in 35 950 35 973 mm 1 4153 1 4163 in 35 941 mm 1 415 in 0 018 mm 0 0007 in 0 025 mm 0 0010 in 0 279 mm 0 0110 in 0 10 mm 0 0039 in Values are in Metric units Values in parentheses are English equivalents 5 Lubricate threads with engine oil prior to assembly Lubricate threads with engine oil prior to assembly 10 KohlerEngines com 24 690 32 Rev A CLEARANCE SPECIFICATIONS Cylinder Bore Specifications PCH680 PCH740 Bore I D New 83 006 83 031 mm 3 2680 3 2689 in O D Max Wear Limit 83 081 mm 3 2709 in Ma
52. 14455 pore T ms SIE TBUNF2BINCH 381 rim CRANKSHAFT men 1K 19 0 21 0X 60 Res BOOT SPARK Ge LH PLUG osia N 10 729 BOOT k OIL FILTER REMOVAL REMOVAL i 15208 j 155 58 15987 6 MOUNTING HOLEN m BE EECH 16305 oam 134 80 3 626 5 307 4X0 10 8 0 425 MOUNTING HOLES THRU an 139 99 184 20 e 15512 7 252 Dag FLYWHEEL SIDE 1226 anaiai sson 50 L p483 ke F ang Mt 10159 JA s ENGINE MOUNTING SURFACE s MONTNGHOLPW T OLDRAIN PLUG 3 2 NPT 99 96 89 00 B339 ba OILFILTER SIDE 50 00 1 969 33479 amp SPARK 113 181 PLUG 15 9 4 2 964 LIFT STRAP SOLENOID SHIFT STARTER AX0210 i 5 16 24 UNF 2B INCHF17 0 Lol jim Si TSK 97 0 90 4 S 4 hae ENGINE MOUNTING SURFACE SE MOUNTING HOLE gps 8 6 DER NOR 210 12 008 MOUNTING HOLE A gt Katie REGULATOR ASSEMBLY 1550 x OIL DRAIN PLUG 3 8 NPT INCH 4X07250 89 00 4 7 N6 14UNF 2BINCHY21 0 ENGINE MOUNTING SURFACE 3 504 15K 913 5 X90 STARTER SIDE PTO SIDE Specifications ENGINE IDENTIFICATION NUMBERS Kohler engine identification numbers model specification and serial should be referenced for efficient repair ordering correct parts and engine replacement Model ae A oumae B a ws PCH680 Propane EFI Command Engine Horizontal Shaft Numerical Designation Specification PCH680 3001 Seral iisiiii4 koks a 4323500328
53. 4 Leave leads connected to pin terminals as described in step 3 Rotate throttle shaft slowly to full throttle position Monitor dial during rotation for indication of any momentary short or open circuits Note resistance at full throttle position It should be 4600 5200 O without a stop pin or 3200 4100 O with a stop pin 5 Disconnect main wiring harness connector from TPS leaving TPS assembled to throttle body Refer to Resistance Table and perform resistance checks indicated between terminals in TPS switch with throttle in positions specified If resistance values in steps 3 4 and 5 are within specifications go to step 6 If resistance values are not within specifications or a momentary short or open circuit was detected during rotation step 4 TPS needs to be replaced go to step 7 6 Check TPS circuits input ground between TPS plug and main harness connector for continuity damage etc Input pin is 12 and ground is pin 10 a Repair or replace as required b Turn idle speed screw back in to its original setting c Reconnect connector plugs start engine and retest system operation 7 Remove two mounting screws from TPS Save screws for reuse Remove and discard faulty TPS Install replacement TPS and secure with original mounting screws a Reconnect Black and TPS connector plugs b Perform TPS Learn Procedure integrating new sensor to ECU Engine Oil Temperature Sensor A sealed non serviceable asse
54. 7 8 N m 69 in Ib finally to 10 5 N m 93 in Ib 7 3 N m 65 in Ib Air Cleaner to Throttle Body Fastener Nut 8 2 N m 73 in Ib Air Cleaner Mounting Bracket Fastener 5 8 N m 51 in Ib Fuel Injector Cap Fastener 7 3 N m 65 in Ib Muffler Retaining Nut Oxygen Sensor 27 8 N m 246 in Ib 50 1 N m 37 ft Ib Values are in Metric units Values in parentheses are English equivalents 5 Lubricate threads with engine oil prior to assembly 8 KohlerEngines com 24 690 32 Rev A Specifications TORQUE SPECIFICATIONS 5 PCH680 PCH740 Oil Cooler Oil Cooler Adapter Nipple 28 5 N m 21 ft Ib Fastener Into Blower Housing 2 8 N m 25 in Ib Between Oil Cooler Hoses 2 3 N m 20 in Ib Speed Control Bracket Fastener assembled to cylinder heads 10 7 N m 95 in Ib into new holes 7 3 N m 65 in Ib into used holes Fastener assembled to blower housing 2 8 N m 25 in Ib into new holes 2 3 N m 20 in Ib into used holes Starter Assembly Thru Bolt 5 6 9 0 N m 49 79 in Ib Mounting Screw 16 0 N m 142 in Ib Brush Holder Mounting Screw 2 5 3 3 N m 22 29 in Ib Starter Solenoid Mounting Hardware 4 0 6 0 N m 35 53 in Ib Nut Positive Brush Lead 8 0 11 0 N m 71 97 in Ib Stator Mounting Screw 6 2 N m 55 in Ib into new holes 4 0 N m 35 in Ib into used holes Valve Cover Fastener 6 2 N
55. 7 in B Oil Seal 1 Make sure that seal bore of crankcase is clean and free of any nicks or burrs 2 Apply a light coat of engine oil to outside diameter of oil seal 3 Drive oil seal into crankcase using a seal driver Make sure oil seal is installed straight and true in bore to depth shown Install Crankshaft 1 Lubricate crankshaft journals and connecting rod bearing surfaces with engine oil 2 Carefully slide flywheel end of crankshaft through main bearing in crankcase Install Connecting Rods with Pistons and Rings Piston Detail A Cylinder 1 B Cylinder 2 NOTE Cylinders are numbered on crankcase Make sure to install piston connecting rod and end cap into its appropriate cylinder bore as previously marked at disassembly Do not mix end caps and connecting rods 24 690 32 Rev A Reassembly NOTE Proper orientation of piston connecting rod assemblies inside engine is extremely important Improper orientation can cause extensive wear or damage Be certain pistons and connecting rods are assembled exactly as shown NOTE Align chamfer of connecting rod with chamfer of its mating end cap When installed flat faces of connecting rods should face each other Faces with raised rib should be toward outside If piston rings were removed see Disassembly Inspection and Service procedure to install new rings Lubricate cylinder bore piston and piston rings wi
56. BOSSES li EXHAUST ep d PORT 1 7127 2 806 71 04 2 797 SPARK PLUG REMOVAL mE SPARK PLUG LIFT STRAP REMOVAL 70 11 2 7601_ 29 81 1 174 SPARK PLUG SPARK PLUG BOOT 80 REMOVAL 4135 1 628 I 2924 1 151 SPARK PG SPARK PLUG BOOT BOOT REMOVAL 319 10 AMAT 12563 17 511 SPARK XU bye 320 65 12 6261 REMOVAL 112 624 SPARK casam SPARK PSO PLUG PLUG BOOT 15 50 BOOT REMOVAL 10610 REMOVAL OILFILTER REMOVAL E MOUNTING HOLE A 9210 ENGINE ENGINE MOUNTING SURFACE n BASI ian 4X 103 0406 MOUNTING HOLES THRU ee 17 252 ee ENGINE MOUNTING SURFACE SCH FLYWHEEL SIDE OIL DRAIN PLUG 3 8 NPT 89 00 MOUNTING HOLE I 3 504 STARTER SIDE 334 79 13 181 le 122 11 7528 353 02 sm 808 2 964 13 898 12 559 20995 MUFFLER p MOUNTING ey 5195 82661 ig MOUNTING Den 2045 amp SPARK PLUG 32 00 1260 EXHAUST PORT 2 6750 Dei MUFFLER MOUNTING BOSSES DIPSTICK 50 00 M8 X 1 25 T1969 ASTUDS EXHAUST 6228 PORT 2 124 499 50 00 MOUNTING 1 969 HOLES 347 0 50 0 EXHAUST 7 16 20 UNF 28 INCHT38 1 PORT 1 SKO 12 5 14 5X 60 MOUNTING HOLES 028 45 1 1204 308 12 I dis 12131 11 164 MUFFLER 155 52 15 987 SOLENOID MOUNTING 16123 OIL FILTER SHIFT as STARTER Dag Or NE 1228 REGULATOR RECTIFIER i j 407 us pem 0483 ti 10 160 2 077 AX0321 0 4X0325 0 4X0125 0 89 00 0 PUT OIL FILTER 3 504 ENGINE MOUNTING SURFACE 5 16 24 UNF 2B INCH 17 0 3 8 16 UNC 2B INCH 21 0 7 64 UNE 2B
57. Manifold Absolute Pressure MAP Sensor 1 With a screwdriver slide locking tab on electrical connector 2 Detach connector 3 Remove screw and pull MAP sensor out of intake manifold Remove Fuel Injectors 1 Disconnect electrical connector 2 Remove screw and pull injector out of intake manifold for each injector 3 When removed pull metal retaining clip connecting fuel injector to fuel injector cap There may be some fuel left in line Any spilled fuel must be cleaned up immediately Remove Intake Manifold 1 Remove screw securing a ring terminal which is part of wiring harness 2 Remove screws securing intake manifold to cylinder heads Note which screws hold wiring clamp 3 Unclasp wiring harness from clip using a screwdriver 4 Remove intake manifold and intake manifold gaskets 5 Leave high pressure fuel line and wiring harness attached to manifold 24 690 32 Rev A Cylinder Head Components Disassembly Inspection and Service Style A Ribbed Remove Valve Covers Remove Spark Plugs A Valve Cover Valve Cover O ring C Hex Flange Screw D Rocker Arm Pivot E Rocker Arm Push Rod G Hydraulic Lifter H Valve Cap l Valve Keeper Valve Spring Valve Seal L m Cylinder Head M Spark Plug Cylinder Head o Gasket P Valve Hydraulic Lifter Hydraulic Lifter Q bowels S style B Smooth 1 Remove screws securing each valve cover Note valv
58. OSTIC AID 4 E CRANKSHAFT POSITION SENSOR lu e YES NO 9 a REFER TO DIAGNOSTIC AID 5 WHILE CRANKING CHECK FUEL LOCK OFF IGNITION SYSTEM we REFER TO DIAGNOSTIC AID 46 IGNITION SYSTEM YES WHILE CRANKING CHECK INJECTOR FUEL DELIVERY ANY NOTAB INTERNAL COMBUSTION YES INSTALL IN LINE PRESSURE GAUGE AND KEY ON NO REFER TO DIAGNOSTIC AID 7 FUEL SYSTEM ELECTRICAL REFER TO DIAGNOSTIC AID 8 IN SPECIFICATION NO FUEL SYSTEM YES REFER TO DIAGNOSTIC AID 9 BASIC ENGINE 1 After turning key to OFF wait 10 seconds before turning to ON to allow ECU to go to sleep 2 Fuel lock off can be heard or felt to establish lock off opening Fuel lock off will stay activated for one 4 6 second cycle when ECU wakes up after being asleep key ON not cranking 46 KohlerEngines com 24 690 32 Rev A Lubrication System This engine uses a full pressure lubrication system which delivers oil under pressure to crankshaft camshaft connecting rod bearing surfaces and hydraulic valve lifters A high efficiency gerotor oil pump maintains high oil flow and oil pressure even at low speeds and high operating temperatures A pressure relief valve limits maximum pressure of system Closure plate must be removed to service oil pickup pressure relief valve and oil pump Lubrication Components A 9 1 A Dipstick B DipstickTube C OilSentry p HS
59. Rev A Install Electric Starter Motor and ECU Bracket Reassembly Install Throttle Body 1 Install electric starter motor using screws Position ECU bracket 2 Torque screws to 16 0 N m 142 in Ib 3 Connect leads to solenoid 4 Install dipstick tube and align mounting hole with threaded hole in ECU bracket Secure with M5 screw Torque screw to 6 2 N m 55 in Ib into new hole or 4 0 N m 35 in Ib into used hole ECU Install Electronic Control Unit ECU A Electronic Control B ECU Bracket Unit ECU Starter NOTE ECU pins should be coated with a thin layer of 24 690 32 Rev A electrical grease to prevent fretting and corrosion and may need to be reapplied if ECU is being reused Install ECU to ECU bracket using screws Torgue M5 screws to 6 2 N m 55 in Ib into new holes or 4 0 N m 35 in Ib into used holes Connect Black and Grey electrical connectors Connectors and ECU are keyed in such a way so they cannot be installed incorrectly NOTE Ensure all parts are clean undamaged and free of debris and make sure electrical connector has seal in place 1 Install a new throttle body O ring prior to installation Make sure all holes align and are open 2 Install throttle body throttle position sensor intake air temperature sensor throttle linkage spring and bushing as an assembly 3 Install air cleaner bracket to throttle body with screws Torq
60. Start engine check for oil leaks Stop engine correct leaks Recheck oil level Dispose of used oil and filter in accordance with local ordinances OIL COOLER if equipped 1 2 3 48 Clean fins with a brush or compressed air Remove screws securing oil cooler and tilt to clean back side Reinstall oil cooler and secure with screws Torque top screw to 2 8 N m 25 in Ib and lower screw to 2 3 N m 20 in Ib KohlerEngines com OIL SENTRY if equipped This switch is designed to prevent engine from starting in a low oil or no oil condition Oil Sentry may not shut down a running engine before damage occurs In some applications this switch may activate a warning signal Read your equipment manuals for more information Oil Sentry pressure switch is installed in breather cover On engines not equipped with Oil Sentry installation hole is sealed with a 1 8 27 N P T F pipe plug Installation 1 Apply pipe sealant with Teflon Loctite PST 592 Thread Sealant or equivalent to threads of switch 2 Install switch into tapped hole in breather cover 3 Torque switch to 4 5 N m 40 in Ib Testing Compressed air a pressure regulator pressure gauge and a continuity tester are required to test switch 1 Connect continuity tester across blade terminal and metal case of switch With O psi pressure applied to Switch tester should indicate no continuity switch open 2 Gradually incre
61. all molded tabs in gear When gear is removed from shaft these tabs are destroyed and gear must be replaced Therefore remove gear only if absolutely necessary Governor gear must be replaced once it is removed from closure plate 1 Remove regulating pin and governor gear assembly 2 Remove locking tab thrust washer located under governor gear assembly 3 Carefully inspect governor gear shaft and replace it only if itis damaged After removing damaged shaft press or lightly tap replacement shaft into closure plate to depth shown Reassembly 1 Install locking tab thrust washer on governor gear shaft with tab down 2 Position regulating pin within governor gear flyweight assembly and slide both onto governor shaft KohlerEngines com 67 Disassembly Inspection and Service Oil Pump Assembly Oil pump is mounted inside closure plate If service is required refer to Disassembly Inspection and Reassembly Disassembly 1 Remove screws 2 Lift oil pump assembly from closure plate Remove outer gerotor gear from closure plate 3 Ensure ball and spring remain installed in pressure relief hole of closure plate If ball and spring fall out of pressure relief hole see reassembly for correct installation 4 Remove oil pump cover O ring from groove in closure plate Inspection Inspect oil pump housing gear and rotors for nicks burrs wear or any visible damage Inspect oil pump cover O ring for cut
62. anifold and injectors are locked into place A small retaining clip provides a secondary lock High pressure fuel line is serviced as a complete assembly to prevent tampering and safety hazards Components are not individually serviceable Vacuum hose connects vaporizer regulator to throttle body compensating regulated pressure for air cleaner condition EFI engines have no carburetor so throttle function regulate incoming combustion airflow is achieved with a throttle valve in a separate throttle body attached to intake manifold Throttle body intake manifold provides mounting for fuel injectors throttle position sensor MAP sensor intake air temperature sensor high pressure fuel line idle speed screw and air cleaner assembly Idle speed is only adjustment that may be performed on EFI system Standard idle speed setting for EFI engines is 1500 RPM but certain applications might require a different setting Check equipment manufacturer s recommendation For starting and warm up ECU will adjust fuel and ignition timing based upon ambient temperature engine temperature and loads present In cold conditions idle speed will probably be different than normal for a few moments Under other conditions idle speed may actually start lower than normal but gradually increase to established setting as operation continues Do not attempt to circumvent this warm up period or readjust idle speed during this time Engine must be comp
63. ase bracket to cylinder heads with screws behind any control panel or bracket Attach air cleaner base to lower bracket with M5 screws through lower section of base Torque nuts to 7 4 9 0 N m 65 5 80 in Ib and lower M5 mounting screws to 2 3 N m 20 in Ib 2 Install air cleaner components as described in Air Cleaner Intake Setting Initial Governor Adjustment 1 Move governor lever toward throttle body as far as it will go wide open throttle and hold in position 2 Insert a nail into hole on cross shaft and rotate shaft counterclockwise as far as it will turn then torque nut to 7 1 N m 63 in Ib Install Muffler 1 Install port liners if equipped Install exhaust gaskets and muffler Install oxygen sensor torque to 50 1 N m 37 ft Ib and connect to wire harness 2 Install remaining muffler support hardware screws and nuts and torque to 9 9 N m 88 in Ib 3 Install nuts to exhaust studs Torque nuts to 27 8 N m 246 in Ib 86 KohlerEngines com 1 2 Secure adapter to closure plate with oil filter nipple Torque oil filter nipple to 28 5 N m 21 ft Ib Verify all fuel and vent hoses are routed properly and not pinched Install screws to secure oil cooler to blower housing Torque top screw to 2 8 N m 25 in Ib and lower screw to 2 3 N m 20 in Ib Install Oil Filter and Fill Crankcase with Oil NOTE If testing oil pressure after completing 5 6
64. ase pressure to switch As pressure increases through range of 2 0 5 0 psi tester should indicate a change to continuity switch closed Switch should remain closed as pressure is increased to 90 psi maximum 3 Gradually decrease pressure through range of 2 0 5 0 psi Tester should indicate a change to no continuity switch open down to 0 psi 24 690 32 Rev A SPARK PLUGS Electrical System Inspection A CAUTION E Electrical Shock can cause injury Do not touch wires while engine is running Spark Plug Component and Details o Bo A Wire Gauge B Spark Plug C Ground Electrode D Gap NOTE Do not clean spark plug in a machine using abrasive grit Some grit could remain in spark plug and enter engine causing extensive wear and damage Engine misfire or starting problems are often caused by a spark plug that has improper gap or is in poor condition Engine is equipped with following spark plugs Gap 0 76 mm 0 03 in Thread Size 14 mm Reach 19 1 mm 3 4 in Hex Size 15 9 mm 5 8 in Refer to Maintenance for Repairs Service Parts Service Clean out spark plug recess Remove plug and replace 1 Check gap using wire feeler gauge Adjust gap to 0 76 mm 0 03 in 2 Install plug into cylinder head 3 Torque plug to 27 N m 20 ft Ib 24 690 32 Rev A Inspect each spark plug as it is removed from cylinder head Deposits
65. ated e Faulty spark plug s e Ignition module s faulty or improperly gapped e Incorrect crankshaft position sensor air gap e Interlock switch is engaged or faulty e Loose wires or connections that intermittently ground ignition kill circuit e Quality of fuel dirt water stale mixture e Spark plug lead s disconnected e Spark plug lead boot loose on plug e Spark plug lead loose Engine Will Not Idle e Faulty carburetor e Faulty cylinder head gasket e Faulty or misadjusted choke or throttle controls e Fuel pump malfunction vacuum hose clogged or leaking e ntake system leak e Loose wires or connections that intermittently ground ignition kill circuit e Quality of fuel dirt water stale mixture e Restricted fuel tank cap vent Engine Starts Hard e Engine overheated e Faulty spark plug s e Idle fuel adjusting needle s improperly set e dle speed adjusting screw improperly set e Inadequate fuel supply e Low compression e Quality of fuel dirt water stale mixture e Restricted fuel tank cap vent Engine Overheats e Clogged fuel line or fuel filter e Engine overheated e Faulty ACR mechanism e Faulty or misadjusted choke or throttle controls e Faulty spark plug s e Flywheel key sheared e Fuel pump malfunction vacuum hose clogged or leaking e Interlock switch is engaged or faulty e Loose wires or connections that intermittently ground ignition kill
66. ation or hard starting A fully charged 12 volt battery with a minimum of 350 cold cranking amps is important in maintaining steady and reliable system operation Battery condition and state of charge should always be checked first when troubleshooting an operational problem Keep in mind that EF I related problems are often caused by wiring harness or connections Even small amounts of corrosion or oxidation on terminals can interfere with milliamp currents used in system operation Cleaning connectors and grounds will solve problems in many cases In an emergency situation simply disconnecting and reconnecting connectors may clean up contacts enough to restore operation at least temporarily If a fault code indicates a problem with an electrical component disconnect ECU connector and test for continuity between component connector terminals and corresponding terminals in ECU connector using an ohmmeter Little or no resistance should be measured indicating that wiring of that particular circuit is OK 24 690 32 Rev A Propane EFI System Crankshaft position sensor is essential to engine operation constantly monitoring rotation and speed RPM of crankshaft There are 23 consecutive teeth cast into flywheel One tooth is missing and is used to reference crankshaft position for ECU Inductive crankshaft position sensor is mounted 0 20 0 70 mm 0 008 0 027 in from flywheel During rotation an AC voltage pulse is created with
67. ay remain attached to baffle after being unplugged or disconnected 5 Remove outer barrel baffles 6 If debris screen overlaps blower housing remove fasteners and screen 7 Remove remaining screws securing blower housing Remove blower housing 8 Remove cooling fan Remove Oil Sentry If Equipped NOTE This is optional Removing Oil Sentry is not required to remove breather cover 1 Disconnect lead from Oil Sentry switch 2 Remove Oil Sentry switch from breather cover Remove Oil Temperature Sensor NOTE Unless oil temperature sensor is damaged or malfunctioning disassembly from breather cover is unnecessary 1 Disconnect lead from oil temperature sensor 2 Remove oil temperature sensor from breather cover Remove Inner Baffles and Breather Cover NOTE Removing oil temperature sensor is not required to remove breather cover or inner baffles Remove screws securing inner baffles to crankcase Remove inner valley baffles Disconnect and remove oil temperature sensor Remove remaining screws from breather cover Pry under protruding edge of breather cover with a screwdriver to break gasket seal Do not pry on sealing surfaces as it could cause damage resulting in leaks 6 Remove breather cover and gasket ak WON gt 62 KohlerEngines com 1 Remove screws securing crankshaft position sensor bracket 2 Disconnect electrical connector to crankshaft position sensor Remove
68. bber grommet into matching recess of drive end cap Molded recesses in grommet should be out matching and aligned with those in end cap Install frame with small notch forward onto armature and drive end cap Align notch with corresponding section in rubber grommet Install drain tube in rear cutout if it was removed previously Install flat thrust washer onto commutator end of armature shaft Starter reassembly when replacing brushes brush holder assembly a Hold starter assembly vertically on end housing and carefully position assembled brush holder assembly with supplied protective tube against end of commutator armature Mounting screw holes in metal clips must be up out Slide brush holder assembly down into place around commutator and install positive brush lead grommet in cutout of frame Protective tube may be saved and used for future servicing Starter reassembly when not replacing brushes brush holder assembly a Carefully unhook retaining caps from brush assemblies Do not lose springs 24 690 32 Rev A Starter System b Position brushes back in their slots so they are flush with I D of brush holder assembly Insert brush installation tool with extension or use tube described above from a prior brush installation through brush holder assembly so holes in metal mounting clips are up out c Install brush springs and snap on retainer caps d Hold starter assembly vertically on end housing an
69. cal Shock can cause injury Do not touch wires while engine is running Propane is extremely flammable and is heavier than air and tends to settle in low areas where a spark or flame could ignite gas Do not start or operate this engine in a poorly ventilated area where leaking gas could accumulate and endanger safety of persons in area To ensure personal safety installation and repair of propane fuel supply systems must be performed only by qualified propane system technicians Improperly installed and maintained propane equipment could cause fuel supply system or other components to malfunction causing gas leaks Observe federal state and local laws governing propane fuel storage and systems Engine exhaust gases contain poisonous carbon monoxide Carbon monoxide is odorless colorless and can cause death if inhaled WARNING Accidental Starts can cause severe injury or death Disconnect and ground spark plug lead s before 24 servicing f Se A CAUTION Damaging Crankshaft and Flywheel can cause Jo personal injury QN Using improper procedures can lead to broken fragments Broken fragments could be thrown from engine Always observe and use precautions and procedures when installing flywheel Before working on engine or equipment disable engine as follows 1 Disconnect spark plug lead s 2 Disconnect negative battery cable from ba
70. circuit e Low compression e Quality of fuel dirt water stale mixture e Weak spark 24 690 32 Rev A e Cooling fan broken e Excessive engine load e Fan belt failed off e Faulty carburetor e High crankcase oil level e Lean fuel mixture e Low cooling system fluid level e Low crankcase oil level e Radiator and or cooling system components clogged restricted or leaking e Water pump belt failed broken e Water pump malfunction Engine Knocks e Excessive engine load e Hydraulic lifter malfunction e Incorrect oil viscosity type e Internal wear or damage e Low crankcase oil level e Quality of fuel dirt water stale mixture KohlerEngines com 17 Troubleshooting Engine Loses Power e Dirty air cleaner element e Engine overheated e Excessive engine load e Restricted exhaust e Faulty spark plug s e High crankcase oil level e Incorrect governor setting e Low battery e Low compression e Low crankcase oil level e Quality of fuel dirt water stale mixture Engine Uses Excessive Amount of Oil e Loose or improperly torqued fasteners e Blown head gasket overheated e Breather reed broken e Clogged broken or inoperative crankcase breather e Crankcase overfilled e Incorrect oil viscosity type e Worn cylinder bore e Worn or broken piston rings e Worn valve stems valve guides Oil Leaks from Oil Seals Gaskets e Breather reed broken
71. connect vent hose from throttle body Remove screws securing air cleaner bracket take off bracket and slide throttle body with linkage and spring connected off intake manifold 1 Remove screws securing ECU to bracket 2 Disconnect Black and Grey electrical connectors from ECU O BON Remove Electronic Control Unit Bracket and Electric Starter Motor 1 Disconnect leads from starter 2 Remove screws ECU bracket and starter assembly 24 690 32 Rev A KohlerEngines com 61 Disassembly Inspection and Service Remove Guard and Debris Screen Remove Crankshaft Position Sensor NOTE Fan will be loose but cannot be removed until after blower housing is removed 1 Remove screws securing guard to blower housing and remove guard and spacers 2 Remove screws securing metal screen and remove Screen 3 Remove support ring spacers and washers paying attention to curvature of spring washers between spacers and fan Remove Outer Barrel Baffles Debris Screen and Blower Housing 1 Disconnect plug from rectifier regulator 2 Remove silver plated rectifier regulator ground strap screw fastened to crankcase Rectifier regulator does not have to be detached from blower housing 3 Disconnect 3 fuse connectors on outer baffle and allow them to hang 4 Remove screws securing outer barrel baffles Note location of any lifting strap and position of short screws for reassembly Coil and any hoses m
72. continuity is measured or very high resistance replace wire harness Check to make sure intake manifold is not loose and MAP sensor is not loose Loose parts would allow a vacuum leak making MAP sensor report misleading information to ECU a Tighten all hardware and perform an ECU Reset and a TPS Learn Procedure to see if MIL will display a fault with MAP sensor again If MIL finds a fault with MAP sensor replace it KohlerEngines com 33 Propane EFI System Fuel Injectors A WARNING High Pressure Fluids can puncture skin and e Cause severe injury or death Do not work on fuel system without proper training or safety eguipment Fluid puncture injuries are highly toxic and hazardous If an injury occurs seek immediate medical attention Details A Electrical Connection B Upper O ring Inlet Filter Calibration C Tube Assembly D Solenoid Winding E Armature F Valve Housing G Valve Seat H Lower O ring NOTE Do not apply voltage to fuel injector s Excessive voltage will burn out injector s Do not ground injector s with ignition ON Injector s will open turn on if relay is energized NOTE When cranking engine with injectors disconnected fault codes will be registered in ECU and will need to be cleared using software fault clear or an ECU Reset and TPS Learn Procedure Injector problems typically fall into three general categories electrical dirty clogged or l
73. ctive sleeve that will also serve as an installation tool Perform steps 10 13 in Starter Reassembly sequence If starter has been disassembled installation must be done after armature drive lever and frame are installed KohlerEngines com Starter Reassembly NOTE Always use a new retainer Do not reuse old retainers that have been removed NOTE Correctly installed center pivot section of drive 10 lever will be flush or below machined surface of housing Apply drive lubricant to armature shaft splines Install drive pinion onto armature shaft Install and assemble stop collar retainer assembly a Install stop collar down onto armature shaft with counter bore recess up b Install a new retainer in larger rear groove of armature shaft Squeeze with a pliers to compress it in groove c Slide stop collar up and lock it into place so recess surrounds retainer in groove If necessary rotate pinion outward on armature splines against retainer to help seat collar around retainer Install offset thrust stop washer so smaller offset of washer faces retainer collar Apply a small amount of oil to bearing in drive end cap and install armature with drive pinion Lubricate fork end and center pivot of drive lever with drive lubricant Position fork end into space between captured washer and rear of pinion Slide armature into drive end cap and at same time seat drive lever into housing Install ru
74. cylinder bore valves and valves guides Check exhaust screen spark arrestor if equipped Clean or replace as needed Repair or replace any other damaged restricted muffler or exhaust system parts 24 690 32 Rev A KohlerEngines com 19 Troubleshooting COMPRESSION TEST For Command Twins A compression test is best performed on a warm engine Clean any dirt or debris away from base of spark plug s before removing them Be sure choke is off and throttle is wide open during test Compression should be at least 160 psi and should not vary more than 1596 between cylinders All other models These engines are eguipped with an automatic compression release ACR mechanism It is difficult to obtain an accurate compression reading because of ACR mechanism As an alternative use cylinder leakdown test described below CYLINDER LEAKDOWN TEST A oylinder leakdown test can be a valuable alternative to a compression test By pressurizing combustion chamber from an external air source you can determine if valves or rings are leaking and how badly Cylinder leakdown tester is a relatively simple inexpensive leakdown tester for small engines This tester includes a quick connect for attaching adapter hose and a holding tool 1 Run engine for 3 5 minutes to warm it up 2 Remove spark plug s and air filter from engine 3 Rotate crankshaft until piston of cylinder being tested is at top dead center TDC of compression str
75. d carefully place tool with extension and assembled original brush holder assembly onto end of armature shaft Slide brush holder assembly down into place around commutator install positive brush lead grommet in cutout of frame 11 Install end cap onto armature and frame aligning thin raised rib in end cap with corresponding slot in grommet of positive brush lead 12 Install thru bolts and brush holder mounting screws Torque bolts to 5 6 9 0 N m 49 79 in Ib and brush holder mounting screws to 2 5 3 3 N m 22 29 in Ib 13 Hook plunger behind upper end of drive lever and install spring into solenoid Insert mounting screws through holes in drive end cap Use these to hold solenoid gasket in position then mount solenoid Torque screws to 4 0 6 0 N m 35 53 in Ib 14 Connect positive brush lead bracket to solenoid and secure with nut Torque nut to 8 11 N m 71 97 in Ib Do not overtighten Solenoid Tests NOTE DO NOT leave 12 volt test leads connected to solenoid for any time over what is necessary for performing each of individual tests Internal damage to solenoid may occur Disconnect all leads from solenoid including positive brush lead attached to lower stud terminal Remove mounting hardware and separate solenoid from starter for testing To test solenoid pull in coil plunger Actuation 1 Use a 12 volt power supply and 2 test leads 2 Connect 1 lead to flat spade S start terminal on solenoid Momentar
76. designated for safe propane tank storage 4 Store engine in a clean dry place 24 690 32 Rev A Engine Dimensions with Heavy Duty Air Cleaner Specifications Dimensions in millimeters 24 690 32 Rev A Ko hlerEngines com 344 13 13 548 p PRIMARY AIR FILTER Inch equivalents shown in ELEMENT REMOVAL 23181 0 126 SAFETY AIR FILTER ELEMENT REMOVAL iis 13254 5 440 5218 a i AIR FILTER COVER AIR FILTER COVER bam ASSEMBLY REMOVAL ASSEMBLY REMOVA 41375 50 00 16289 VALVE COVER 1 969 SPARK PLUG 67 50 2 657 L 1200 MUFFLER MOUNTING i 0472
77. e Components of 24 761 01 S Fuel Pressure Tester Noid Light 90 Adapter In line T Fitting Code Plug Red Wire Code Plug Blue Wire Shrader Valve Adapter Hose Kohler 24 761 01 S Design Technology Inc DTI 019 DTI 021 DTI 023 DTI 035 DTI 027 DTI 029 DTI 037 Flywheel Puller For properly removing flywheel from engine SE Tools KLR 82408 14 KohlerEngines com 24 690 32 Rev A TOOLS Description Tools and Aids Source Part No Hydraulic Valve Lifter Tool For removing and installing hydraulic lifters Kohler 25 761 38 S Ignition System Tester For testing output on all systems including CD Kohler 25 455 01 S Inductive Tachometer Digital For checking operating speed RPM of an engine Design Technology Inc DTI 110 Offset Wrench K and M Series For removing and reinstalling cylinder barrel retaining nuts Kohler 52 455 04 S Cil Pressure Test Kit For testing verifying oil pressure on pressure lubricated engines Kohler 25 761 06 S Rectifier Regulator Tester 120 volt current Rectifier Regulator Tester 240 volt current For testing rectifier regulators Components of 25 761 20 S and 25 761 41 S CS PRO Regulator Test Harness Special Regulator Test Harness with Diode Spark Advance Module SAM Tester For testing SAM ASAM and DSAM on engines with SMART SPARK Starter Servicing Kit All Starters For removing and reinstalling drive retaining
78. e Wiring Harness Related e Engine is operating above 176 C e Pin circuits Black 10 and Black 8 may 350 F temperature sensor limit be damaged or routed near noisy signal coils alternator etc e ECU to harness connection problem 40 KohlerEngines com 24 690 32 Rev A Propane EFI System Code 0122 Code 0131 Component Throttle Position Sensor TPS Component Oxygen Sensor Fault TPS Circuit Low Voltage or Open Fault O28 1 Circuit Low Voltage Condition Open connection broken wire or faulty Condition Open connection broken wire or faulty sensor sensor Conclusion TPS Related Conclusion Oxygen Sensor Related e TPS bad or worn internally e Sensor connector or wiring problem e Sensor contaminated corroded or Engine Wiring Harness Related damaged e Broken or shorted wire in harness e Poor ground path ECU Black pin 10 to TPS pin 1 e Pin circuit wiring or connectors ECU Black pin 12 to TPS pin 3 ECU Black pin 10 or 17 ECU Black pin 16 to TPS pin 2 TPS Learn Procedure Incorrect Throttle Body Related e Lean condition check oxygen sensor e Throttle shaft inside TPS worn broken signal with VOA and see Oxygen or damaged Sensor section e Throttle plate loose or misaligned e Throttle plate bent or damaged Engine wiring harness related such as a allowing extra airflow past or restricting cut wire broken or pinched movement CH ESSA Code 0132 ela
79. e cover differences for proper location in reassembly Ensure any brackets removed are reassembled in same location 2 Covers should lift off without prying 24 690 32 Rev A Remove spark plug from each cylinder head KohlerEngines com 63 Disassembly Inspection and Service Remove Cylinder Heads and Hydraulic Lifters 1 Remove nuts and washers securing each cylinder head Discard nuts and washers once removed Do not reuse Studs if present should only be removed if damaged or if cylinder reconditioning is necessary Once removed they must be replaced 2 Mark location of push rods as either intake or exhaust and cylinder 1 or 2 Push rods should always be reinstalled in same positions 3 Carefully remove push rods cylinder heads and head gaskets 4 Remove lifters from lifter bores Use a hydraulic lifter tool Do not use a magnet to remove lifters Mark lifters by location as either intake or exhaust and cylinder 1 or 2 Hydraulic lifters should always be reinstalled in same position Inspection Check base surface of hydraulic lifters for wear or damage If lifters need to be replaced apply a liberal coating of Kohler lubricant see Tools and Aids to base of each new lifter before it is installed Bleeding Lifters Style A Ribbed To prevent a possible bent push rod or broken rocker arm it is important to bleed any excess oil out of lifters before they are installed 1 Cuta 50 75 mm 2 3 in p
80. e injury or death Do not work on fuel system without proper training or safety equipment Vaporizer Regulator Lock Off Details m MD A Brass Plug B Inlet Fitting Cc Seen D Button Filter Gasket E O Ring F Nut G Lock Off H Lock Off Valve Body l Plunger J Screen K Outlet Fitting Ensure there is an adequate supply of fuel in tank and that fuel valve is turned ON Vaporizer Regulator is preset at factory is not serviceable and must be replaced if determined to be faulty If a regulator problem is suspected make certain lock off is being activated all electrical connections are properly secured fuses are good and a minimum of 7 0 volts is being supplied If required testing of regulator and lock off may be conducted 1 Relieve fuel pressure at lock off Shut off tank valve If possible run engine in a well ventilated area until fuel system is empty and engine stops If unable to run engine work in a well ventilated area and carefully loosen inlet fuel fitting on vaporizer regulator slowly venting off fuel from line When fuel is dispensed retighten fitting and remove quick connect fitting to allow fuel to escape from line Insert pressure test jumper from Kohler EFI Service Kit between high pressure fuel line and fuel lock off KohlerEngines com 35 Propane EFI System 2 Turn on key switch to activate lock off and check system pressure on gauge If
81. eakage An electrical problem usually causes one or both of injectors to stop functioning Several methods may be used to check if injectors are operating 1 With engine running at idle listen for a buzzing or clicking sound 2 Disconnect electrical connector from an injector and listen for a change in idle performance only running on one cylinder or a change in injector noise or vibration 34 KohlerEngines com If an injector is not operating it can indicate either a bad injector or a wiring electrical connection problem Check as follows 1 Disconnect electrical connector from both injectors Plug a 12 volt noid light into one connector 2 Make sure all safety switch requirements are met Crank engine and check for flashing of test light Turn key OFF for at least 10 seconds between tests to allow ECU to go to sleep and reawake Repeat test at other connector a If flashing occurs use an ohmmeter Rx1 scale and check resistance of each injector across two terminals Proper resistance is 7 9 O If injector resistance is correct check whether connector and injector terminals are making a good connection If resistance is not correct replace injector Check all electrical connections connectors and wiring harness leads if resistance is incorrect Injector leakage is very unlikely but in those rare instances it can be internal past tip of valve needle or external weeping around injector O rings Loss of Sy
82. es See valve details and specifications 24 690 32 Rev A Hard starting or loss of power accompanied by high fuel consumption may be symptoms of faulty valves Although these symptoms could also be attributed to worn rings remove and check valves first After removal clean valve heads faces and stems with a power wire brush Then carefully inspect each valve for defects such as a warped head excessive corrosion or a worn stem end Replace valves found to be in bad condition KohlerEngines com 65 Disassembly Inspection and Service Valve Guides If a valve guide is worn beyond specifications it will not guide valve in a straight line This may result in burnt valve faces or seats loss of compression and excessive oil consumption To check valve guide to valve stem clearance thoroughly clean valve guide and using a split ball gauge measure inside diameter of guide Then using an outside micrometer measure diameter of valve stem at several points on stem where it moves in valve guide Use largest stem diameter to calculate clearance by subtracting stem diameter from guide diameter If intake clearance exceeds 0 038 0 076 mm 0 0015 0 0030 in or exhaust clearance exceeds 0 050 0 088 mm 0 0020 0 0035 in determine whether valve stem or guide is responsible for excessive clearance Maximum I D wear on intake valve guide is 7 134 mm 0 2809 in while 7 159 mm 0 2819 in is maximum allowed on exhaust guide Guides are not
83. es not provide ring gear as a serviceable part Replace flywheel if ring gear is damaged Remove Stator and Backing Plate 1 Remove screws securing backing plate Remove backing plate 2 Remove screws and stator Note position routing of stator lead Remove Closure Plate Assembly 1 Remove screws securing closure plate to crankcase 2 Locate splitting tabs cast into perimeter of closure plate Insert drive end of a 1 2 in breaker bar between splitting tab and crankcase and turn it to loosen seal Do not pry on sealing surfaces as this can cause leaks Inspection Inspect oil seal in closure plate and remove it if it is worn or damaged Refer to Install Closure Plate Oil Seal in Reassembly for new oil seal installation Inspect main bearing surface for wear or damage refer to Specifications Replace closure plate assembly if required 24 690 32 Rev A Disassembly Inspection and Service Governor Gear Assembly Governor Shaft Press Depth Details A Gear Shaft B 19 40 mm 0 7638 in C 34 0 mm 1 3386 in 33 5 mm 1 3189 in Governor gear assembly is located inside closure plate If service is reguired continue with Inspection Disassembly and Reassembly Inspection Inspect governor gear teeth Replace gear if it is worn chipped or if any teeth are missing Inspect governor weights They should move freely in governor gear Disassembly NOTE Governor gear is held onto shaft by sm
84. flow of primary current in coil causing electromagnetic flux field to collapse Flux collapse induces an instantaneous high voltage in coil secondary which is strong enough to bridge gap on spark plug Each coil fires every other revolution EFI engines are equipped with either a 20 or 25 amp charging system to accommodate combined electrical demands of ignition system and specific application Charging system troubleshooting information is provided in Electrical System When key switch is turned ON and all safety switch requirements are met ECU activates lock off valve for about six seconds which pressurizes system for start up If key switch is not promptly turned to start position engine fails to start or engine is stopped with key switch ON as in case of an accident ECU switches off lock off valve preventing continued delivery of fuel In this situation MIL will go on but it will go back off after 4 cranking revolutions if system function is OK Once engine is running lock off valve remains on There are two filters in system one on inlet of vaporizer regulator will be a 30 micron button filter and one after will be a special metal 10 micron filter Be sure to use metal propane 10 micron filter for replacement High pressure fuel line is an assembly of hoses injector caps and a fuel connector to vaporizer regulator High pressure fuel line feeds fuel to top of injectors through injector caps Caps are fastened to intake m
85. gap using wire feeler gauge Adjust gap to 0 76 mm 0 03 in Install plug into cylinder head Torque plug to 27 N m 20 ft Ib KohlerEngines com 79 Reassembly External Engine Components Aj m m le Oil Filter Nipple Bi Air Temperature Throttle Body Oil Cooler Oil Cooler O Ring G Sensor Assembly Barrel Baffle Oil Temperature K Valley Baffle Oil Sentry Sensor M Dipstick Tube Dipstick o ET Breather Cover Q Ignition Coil Md c E e peru Intake Manifold U MAP Sensor TE no asso W Fuel Quick Connect Debris Screen 80 KohlerEngines com 24 690 32 Rev A Install Intake Manifold Reassembly Install Manifold Absolute Pressure MAP Sensor Torque Sequence 1 Install intake manifold with high pressure fuel line assembly and new gaskets with wiring harness attached to cylinder heads Slide any wiring harness clips onto appropriate bolts before installing Make sure gaskets are in proper orientation Using sequence shown torque screws in 2 stages first to 7 8 N m 69 in Ib then to 10 5 N m 93 in Ib 2 Install ground terminal to crankcase post with a silver screw Torque to 4 0 N m 35 in Ib into used holes or 6 2 N m 55 in Ib in new holes 3 Install wire harness clip to other crankcase post Torque to 4 0 N m 35 in Ib into used holes or 6 2 N m 55 in Ib in new holes 4 Place wire harness conduit in clip
86. h could cause severe engine damage Removing crankpin plug when crankshaft is ground provides easy access for removing any grinding deposits collected in oil passages Use these following procedures to remove and replace plug Procedure to Remove Crankshaft Plug 1 Drill a 3 16 in hole through plug in crankshaft 2 Thread a 3 4 in or 1 in long self tapping screw with a flat washer into drilled hole Flat washer must be large enough to seat against shoulder of plug bore 3 Tighten self tapping screw until it draws plug out of crankshaft Procedure to Install New Plug Use a single cylinder camshaft pin as a driver and tap plug into plug bore until it seats at bottom of bore Make sure plug is tapped in evenly to prevent leakage Remove Flywheel End Oil Seal Remove oil seal from crankcase KohlerEngines com 71 Disassembly Inspection and Service Crankcase Inspection and Service Check all gasket surfaces to make sure they are free of gasket fragments Gasket surfaces must also be free of deep scratches or nicks Inspect main bearing if so equipped for wear or damage refer to Specifications Replace crankcase using a miniblock or short block as required Check cylinder bore wall for scoring In severe cases unburned fuel can cause scuffing and scoring of cylinder wall It washes necessary lubricating oils off piston and cylinder wall As raw fuel seeps down cylinder wall piston rings make metal to metal
87. iece from end of an old push rod and chuck it in a drill press 2 Lay arag or shop towel on table of drill press and place lifter open end up on towel 3 Lower chucked push rod until it contacts plunger in lifter Slowly pump plunger 2 or 3 times to force oil out of feed hole in side of lifter 64 KohlerEngines com Bleeding Lifters Style B Smooth To prevent a possible bent push rod or broken rocker arm it is important to bleed any excess oil out of lifters before they are installed 1 Lay a rag or shop towel on table of drill press Place an 8 mm 5 16 in socket on towel with well end up then place open end of lifter on socket Ensure Socket does not contact lifter ball surface 2 Place some material such as wood plastic or aluminum on top of lifter to protect lifter finish 3 Lower drill press chuck until it contacts material on lifter Slowly pump lifter 2 or 3 times to force oil out of feed hole in side of lifter Disassemble Cylinder Heads NOTE These engines use valve stem seals on intake and exhaust valves Use a new seal whenever valve is removed or if seal is deteriorated or damaged in any way Never reuse an old seal 1 Remove screws rocker arm pivots and rocker arms from cylinder head 2 Compress valve springs using a valve spring compressor 3 Once valve spring is compressed remove valve spring keepers then remove following items e Valve spring retainers e Valve springs e Valve s
88. il Position timing mark of crankshaft gear at 12 o clock position Turn governor cross shaft clockwise until lower end of shaft contacts cylinder Make sure cross shaft remains in this position while installing camshaft Slide camshaft into bearing surface of crankcase positioning timing mark of camshaft gear at 6 o clock position Make sure camshaft gear and crankshaft gear mesh with both timing marks aligned KohlerEngines com 75 Reassembly Oil Pump Assembly Oil pump is mounted inside closure plate If service was required and oil pump was removed refer to assembly procedures under Oil Pump Assembly in Disassembly Inspection and Service Governor Gear Assembly Governor gear assembly is located inside closure plate If service was required and governor was removed refer to assembly procedures under Disassembly Inspection and Service Install Closure Plate Oil Seal Oil Seal Details A Oil Seal B 6 5 mm 0 255 in 1 Check to make sure that there are no nicks or burrs in crankshaft bore of closure plate 2 Apply a light coat of engine oil to outside diameter of oil seal 3 Drive oil seal into closure plate using a seal driver Make sure oil seal is installed straight and true in bore to depth shown Install Closure Plate Assembly 1 Be sure sealing surfaces have been cleaned and prepared 2 Check to make sure there are no nicks or burrs on sealing surfaces
89. ily connect other lead to lower large post terminal When connection is made solenoid should energize audible click and plunger retract Repeat test several times Continuity 1 Use an ohmmeter set to audible or Rx2K scale and connect 2 ohmmeter leads to 2 large post terminals 2 Perform solenoid pull in coil plunger actuation test and check for continuity Ohmmeter should indicate continuity Repeat test several times To test solenoid hold in coil Function 1 Connect a 12 volt test lead to flat spade S start terminal on solenoid and other lead to body or mounting surface of solenoid 2 Manually push plunger IN and check if coil holds plunger retracted Do not allow test leads to remain connected to solenoid for a prolonged period of time Continuity 1 Use an ohmmeter set to audible or Rx2K scale and connect 2 ohmmeter leads to 2 large post terminals 2 Perform preceding solenoid hold in coil function test and check for continuity Meter should indicate continuity Repeat test several times Condition Conclusion Solenoid fails to activate Replace solenoid No continuity is indicated Plunger fails to stay retracted 24 690 32 Rev A KohlerEngines com 57 Disassembly Inspection and Service WARNING death xf Nez Accidental Starts can cause severe injury or Disconnect and ground spark plug lead s before servicing Before working on engine or equipment disable engine as foll
90. in sensor for each passing tooth ECU calculates engine speed from time interval between consecutive pulses gap from missing tooth creates an interrupted input signal corresponding to specific crankshaft position near BDC for cylinder 1 This signal serves as a reference for control of ignition timing by ECU Synchronization of inductive speed pickup and crankshaft position takes place during first two revolutions each time engine is started Sensor must be properly connected at all times If sensor becomes disconnected for any reason engine will quit running Throttle position sensor TPS is used to indicate throttle plate angle to ECU Since throttle by way of governor reacts to engine load angle of throttle plate is directly related to load on engine Mounted on throttle body and operated directly off end of throttle shaft TPS works as a potentiometer varying voltage signal to ECU in direct correlation to angle of throttle plate This signal along with other sensor signals is processed by ECU and compared to internal preprogrammed maps to determine required fuel and ignition settings for amount of load Correct position of TPS is established and set at factory Do not loosen TPS or alter mounting position unless absolutely required by fault code diagnosis If TPS is loosened or repositioned appropriate TPS Learn Procedure must be performed to re establish baseline relationship between ECU and TPS Engine oil temperature
91. ing or shorting while engine is running This could damage stator These engines are equipped with a 20 or 25 amp regulated charging system 20 25 Amp Regulated Charging System IE A Battery B Starter Fuse D Rectifier Regulator Flywheel Stator E Connector Block Assembly Stator Stator is mounted on crankcase behind flywheel Follow procedures in Disassembly and Reassembly if stator replacement is necessary Rectifier Regulator NOTE When installing rectifier regulator take note of terminal markings and install plug s accordingly NOTE Disconnect all electrical connections attached to rectifier regulator Testing may be performed with rectifier regulator mounted or loose Repeat applicable test procedure 2 or 3 times to determine condition of part Rectifier regulator is mounted on blower housing To replace disconnect plug s remove mounting screws and ground wire or metal grounding strap Testing rectifier regulator may be performed as follows using appropriate rectifier regulator tester To test 20 25 amp rectifier regulators 1 Connect tester ground lead with spring clamp to body of rectifier regulator 2 Connect red lead from tester to middle terminal labeled B 3 Connect black leads from tester to both outer AC terminals on rectifier regulator 4 Plug tester into proper AC outlet p
92. ipment could cause fuel supply system or other components to malfunction causing gas Observe federal state and local laws governing propane fuel storage and systems 60 KohlerEngines com 24 690 32 Rev A Disassembly Inspection and Service Remove Vaporizer Regulator Lock Off A Vacuum Line B Vaporizer Regulator C Inlet Fitting D Lock Off Assembly E Outlet Fitting F Oetiker Clamp G Propane Fuel Filter H Bracket 1 Disconnect electrical plug from lock off ECU 2 Disconnect vacuum line from front of vaporizer regulator m Electronic Control Unit ECU 3 Loosen nut on center back of vaporizer regulator Keep all fuel lines connected then lift up on regulator so nut comes through key hole slot in bracket removing vaporizer regulator from bracket keeping fuel lines propane fuel filter assembled Separate parts only if additional service is required Do not cut Oetiker clamps unless fuel lines and or propane fuel filter are being replaced 4 Remove screws securing regulator bracket to crankcase Remove Throttle Body l b 1 Disconnect intake air temperature sensor connector ERU from sensor in throttle body Sensor can stay in gt throttl it is bei laced d Mo beu A Up a Electronic Control ECU Bracket Disconnect breather tube from throttle body A Unit ECU B Disconnect throttle position sensor connector C Starter Dis
93. l valve stems and valve guides Install following items in order listed below using a valve spring compressor Intake and exhaust valves Valve spring retainers Valve springs Valve spring caps Valve spring keepers Install Cylinder Heads Torque Sequence NOTE Match numbers embossed on cylinder heads and crankcase 1 Check to make sure there are no nicks or burrs on sealing surfaces of cylinder head or crankcase 2 Ifall of studs were left intact go to Step 6 If any studs were disturbed or removed install new studs as described in Step 3 Do not use reinstall any loosened or removed studs 3 Install new mounting stud s into crankcase a Thread and lock mounting nuts together on smaller diameter threads b Thread opposite end of stud with preapplied locking compound into crankcase until specified height from crankcase surface is achieved When threading in studs use a steady tightening motion without interruption until proper height is obtained Otherwise frictional heat from engaging threads may cause locking compound to set up prematurely 24 690 32 Rev A Reassembly Studs closest to lifters must have an exposed height of 75 mm 2 15 16 in Studs furthest from lifters must have an exposed height of 69 mm 2 3 4 in c Remove nuts and repeat procedure as required 4 Check that dowel pins are in place and install a new cylinder head gasket part number facing
94. l can cause fires and severe burns e 4 If a gaseous odor is detected ventilate area and contact an authorized service technician Propane is extremely flammable and is heavier than air and tends to settle in low areas where a spark or flame could ignite gas Do not start or operate this engine in a poorly ventilated area where leaking gas could accumulate and endanger safety of persons in area To ensure personal safety installation and repair of propane fuel supply systems must be performed only by qualified propane system technicians Improperly installed and maintained propane equipment could cause fuel supply system or other components to malfunction causing gas leaks Observe federal state and local laws governing propane fuel storage and systems Typical propane electronic fuel injection EFI system and related components include e Vaporizer regulator e Fuel filter e High pressure fuel line e Fuel line s e Gaseous propane fuel injectors e Throttle body intake manifold e Electronic control unit ECU e Ignition coils e Engine oil temperature sensor e Throttle position sensor TPS e Crankshaft position sensor e Oxygen sensor e Manifold absolute pressure sensor MAP e Wire harness assembly amp affiliated wiring e Malfunction indicator light MIL optional e Intake air temperature sensor FUEL RECOMMENDATIONS Refer to Maintenance FUEL LINE High pre
95. l conditions A smaller capacity battery is often sufficient if an application is started only in warmer temperatures Refer to following table for minimum capacities based on anticipated ambient temperatures Actual cold cranking reguirement depends on engine size application and starting temperatures Cranking reguirements increase as temperatures decrease and battery capacity shrinks Refer to equipment s operating instructions for specific battery requirements Battery Size Recommendations Temperature Battery Required Above 32 F 0 C 200 cca minimum O F to 32 F 18 C to 0 C 250 cca minimum 5 F to O F 21 C to 18 C 300 cca minimum 10 F 23 C or below 400 cca minimum If battery charge is insufficient to turn over engine recharge battery Battery Maintenance Regular maintenance is necessary to prolong battery life Battery Test To test battery follow manufacturer s instructions 50 KohlerEngines com 24 690 32 Rev A Electrical System BATTERY CHARGING SYSTEM NOTE Observe following guidelines to avoid damage to electrical system and components e Make sure battery polarity is correct A negative ground system is used e Disconnect rectifier regulator plug and or wiring harness plug before doing any electric welding on equipment powered by engine Also disconnect all other electrical accessories in common ground with engine e Prevent stator AC leads from touch
96. lated e Exhaust leak e Fuel lock off open or shorted internally seo tonne Engine Wiring Harness related Poor system ground from ECU to engine e Broken or shorted wire in harness causing rich running while indicating lean ECU pin Black 9 or Grey 17 Fuel lock off connection See Fuel ECU Related Components e ECU is damaged Code 0201 Code 0232 Component Fuel Injector Component Fuel Lock off Fault Injector 1 Circuit Malfunction Fault Circuit High Voltage Condition Injector damaged or faulty shorted or Condition _ Shorted connection open connection Conclusion Fuel Lock off Related Conclusion Injector Related e Fuel lock off damaged internally e Injector coil shorted or opened Charging Output System Too High Engine Wiring Harness Related e Broken or shorted wire in harness ECU pin Black 5 e Wiring from Ignition ECU Related e Circuit controlling injector 1 damaged 24 690 32 Rev A KohlerEngines com 43 Propane EFI System Code 0336 Code 0351 Component Crankshaft Position Sensor Component Ignition Coil Fault Crankshaft Position Sensor Noisy Signal Fault Cylinder 1 Ignition Coil Malfunction Condition Air gap incorrect loose sensor faulty bad Condition Broken wire in harness may not be battery shorted or faulty connection visible shorted connection or faulty
97. le screws with exception of rectifier regulator grounding bracket screw Torque all blower housing and baffle M6 screws assembled into aluminum to 10 7 N m 95 in Ib for a new hole or 7 3 N m 65 in Ib for a used hole Torque all blower housing and baffle M5 screws assembled into sheet metal backing plate to 2 8 N m 25 in Ib for new holes or 2 3 N m 20 in Ib for used holes If an overlapping style debris screen is used attach it to flywheel fan Torque screws to 2 2 N m 20 in Ib Torque breather cover screws to 11 3 N m 100 in Ib into new holes or 7 3 N m 65 in Ib into used holes in sequence shown Note first screw is torqued a second time Install Reconnect Rectifier Regulator NOTE Rectifier regulator middle terminal B is offset not equally spaced from outer terminals AC Verify rectifier regulator plug is assembled to match terminal offset of rectifier regulator Install rectifier regulator in blower housing if removed previously then secure grounding bracket against outer side of rectifier regulator with a silver screw Torque black rectifier regulator screws to 1 4 N m 12 6 in lb and silver ground strap screw to 2 8 N m 25 in Ib into new holes or 2 3 N m 20 in Ib into used holes Connect plug to rectifier regulator If purple wire was removed verify locking tang is raised on terminal and push wire terminal into plug prior to connecting to rectifier regulator 24 690 32
98. lead s Se 3 before servicing Accidental Starts can cause severe injury or Before working on engine or equipment disable engine as FO death follows 1 Disconnect spark plug lead s 2 Disconnect negative battery cable from battery Normal maintenance replacement or repair of emission control devices and systems may be performed by any repair establishment or individual however warranty repairs must be performed by a Kohler authorized dealer MAINTENANCE SCHEDULE Every 25 Hours e Service replace low profile precleaner if equipped Air Cleaner Intake Every 100 Hours e Check oil cooler fins clean as necessary if equipped Air Cleaner Intake e Change oil Lubrication System e Replace low profile air cleaner element if equipped Air Cleaner Intake e Remove cooling shrouds and clean cooling areas Air Cleaner Intake Every 150 Hours e Check heavy duty filter minder Air Cleaner Intake e Inspect heavy duty air filter paper element and inlet screen area Air Cleaner Intake Every 200 Hours e Change oil filter Lubrication System e Replace unique EFI fuel filters Every 300 Hours e Replace heavy duty air cleaner element and check inner element Air Cleaner Intake Every 500 Hours or Annually e Check all lines high pressure vacuum including fittings for leaks Fuel System e Drain va
99. lectrical connector has seal in place Lightly lubricate oil temperature sensor O ring and install oil temperature sensor into breather cover Torque sensor to 7 3 N m 65 in Ib Push electrical connector on oil temperature sensor making sure a good connection is made Install Oil Sentry If equipped 1 82 Apply pipe sealant with Teflon Loctite 592 PST Thread Sealant or equivalent to threads of Oil Sentry switch and install it into breather cover Torque to 4 5 N m 40 in Ib Connect wire lead green to Oil Sentry terminal KohlerEngines com Install Blower Housing Outer Baffles and Debris Screen NOTE Do not completely tighten screws until all items 1 2 are installed to allow shifting for hole alignment Connect plug to key switch in blower housing if equipped Slide blower housing into position over front edge of inner baffles Start a few screws to hold it in place Position outer baffles and secure using M6 screws Install M6 screws 20 mm long into intake port side of cylinder heads including any lifting strap Install M6 screws 16 mm long into exhaust port side of cylinder head Install short M5 screws 10 mm long in upper mounting holes of outer baffles into backing plate Be sure any leads are routed out through proper offsets or notches so they will not be pinched between blower housing and baffles Insert and tighten all remaining blower housing and baff
100. letely warmed up in closed loop operating mode for accurate idle adjustment 24 690 32 Rev A IMPORTANT NOTES e Cleanliness is essential and must be maintained at all times when servicing or working on EFI system Dirt even in small quantities can cause significant problems Clean any joint or fitting with parts cleaning solvent before opening to prevent dirt from entering system Always depressurize fuel system before disconnecting or servicing any fuel system components Shut off tank valve If possible run engine in a well ventilated area until fuel system is empty and engine stops If unable to run engine work in a well ventilated area and carefully loosen inlet fuel fitting on vaporizer regulator slowly venting off fuel from line When fuel is dispensed retighten fitting and remove quick connect fitting to allow fuel to escape from line Never attempt to service any fuel system component while engine is running or ignition switch is ON Do not use compressed air if system is open Cover any parts removed and wrap any open joints with plastic if they will remain open for any length of time New parts should be removed from their protective packaging just prior to installation Avoid direct water or spray contact with system components Propane EFI System Do not disconnect or reconnect ECU wiring harness connector or any individual components with ignition on This can send a damaging voltage spike through ECU
101. lways be a thorough scrubbing with a brush and hot soapy water Use a strong detergent capable of breaking down machining oil while maintaining a good level of suds If suds break down during cleaning discard dirty water and start again with more hot water and detergent Following scrubbing rinse cylinder with very hot clear water dry it completely and apply a light coating of engine oil to prevent rusting 24 690 32 Rev A Disassembly Inspection and Service Measuring Piston to Bore Clearance Piston Detail A A 6 mm 0 24 in NOTE Do not use a feeler gauge to measure piston to bore clearance it will yield inaccurate measurements Always use a micrometer Before installing piston into cylinder bore it is necessary clearance be accurately checked This step is often overlooked and if clearances are not within specifications engine failure will usually result Use these following procedures to accurately measure piston to bore clearance 1 Use a micrometer and measure diameter of piston 6 mm 0 24 in above bottom of piston skirt and perpendicular to piston pin 2 Usean inside micrometer telescoping gauge or bore gauge and measure cylinder bore Take measurement approximately 63 5 mm 2 5 in below top of bore and perpendicular to piston pin 3 Piston to bore clearance is difference between bore diameter and piston diameter step 2 minus step 1
102. mbly A faulty sensor must be replaced If a blink code indicates a problem with temperature sensor it can be tested as follows 1 Remove temperature sensor from breather cover and cap or block sensor hole 2 Wipe sensor clean and allow it to reach room temperature 25 C 77 F 3 Unplug Black connector from ECU 4 With sensor still connected check temperature sensor circuit resistance between Black pin 10 and 14 terminals Value should be 9000 11000 Q 5 Unplug sensor from wire harness and check sensor resistance separately across two pins Resistance value should again be 9000 11000 O a If resistance is out of specifications replace temperature sensor b If itis within specifications proceed to Step 6 24 690 32 Rev A 6 Check circuits input ground from wire harness connector to sensor plug for continuity damage etc Connect one ohmmeter lead to Black pin 14 in wire harness connector as in step 4 Connect other lead to terminal 1 in sensor plug Continuity should be indicated Repeat test between Black pin 10 and terminal 2 in sensor plug Intake Air Temperature Sensor A non serviceable component Complete replacement is required if it is faulty Sensor and wiring harness can be checked as follows 1 Remove temperature sensor from throttle body 2 Allow it to reach room temperature 20 C 68 F 3 Unplug Black connector from ECU 4 With sensor still connected check temperature sen
103. mshaft Endplay Plate For checking camshaft endplay SE Tools KLR 82405 Camshaft Seal Protector Aegis For protecting seal during camshaft installation SE Tools KLR 82417 Cylinder Leakdown Tester Individual component available Adapter 12 mm x 14 mm Required for leakdown test on XT 6 engines For checking combustion retention and if cylinder piston rings or valves are worn Kohler 25 761 05 S Design Technology Inc DTI 731 03 Dealer Tool Kit Domestic Complete kit of Kohler required tools Components of 25 761 39 S Ignition System Tester Cylinder Leakdown Tester Oil Pressure Test Kit Rectifier Regulator Tester 120 V AC 60Hz Kohler 25 761 39 S Kohler 25 455 01 S Kohler 25 761 05 S Kohler 25 761 06 S Kohler 25 761 20 S Dealer Tool Kit International Complete kit of Kohler required tools Components of 25 761 42 S Ignition System Tester Cylinder Leakdown Tester Oil Pressure Test Kit Rectifier Regulator Tester 240 V AC 50Hz Kohler 25 761 42 S Kohler 25 455 01 S Kohler 25 761 05 S Kohler 25 761 06 S Kohler 25 761 41 S Digital Vacuum Pressure Tester For checking crankcase vacuum DTI 721 01 Individual component available Design Technology Inc Rubber Adapter Plug DTI 721 10 Design Technology Inc Electronic Fuel Injection EFI Diagnostic Software For Laptop or Desktop PC Kohler 25 761 23 S EFI Service Kit For troubleshooting and setting up an EFI engin
104. n Ib 10 M4 1 2 11 1 7 15 2 9 26 4 1 36 5 0 44 2 0 18 M5 2 5 22 3 2 28 5 8 51 8 1 72 9 7 86 4 0 35 M6 4 3 38 5 7 50 9 9 88 14 0 124 16 5 146 6 8 60 M8 10 5 93 13 6 120 24 4 216 33 9 300 40 7 360 17 0 150 Tightening Torque N m ft Ib 10 M10 21 7 16 27 1 20 47 5 35 66 4 49 81 4 60 33 9 25 M12 36 6 27 47 5 35 82 7 61 116 6 86 139 7 103 61 0 45 M14 58 3 43 76 4 56 131 5 97 184 4 136 219 7 162 94 9 70 Torque Conversions N m in Ib x 0 113 in Ib N mx 8 85 N m ft Ib x 1 356 ft Ib N m x 0 737 24 690 32 Rev A KohlerEngines com 13 Tools and Aids Certain quality tools are designed to help you perform specific disassembly repair and reassembly procedures By using these tools you can properly service engines easier faster and safer In addition you ll increase your service capabilities and customer satisfaction by decreasing engine downtime Here is a list of tools and their source SEPARATE TOOL SUPPLIERS Kohler Tools SE Tools Design Technology Inc Contact your local Kohler source of 415 Howard St 768 Burr Oak Drive supply Lapeer MI 48446 Westmont IL 60559 Phone 810 664 2981 Phone 630 920 1300 Toll Free 800 664 2981 Fax 630 920 0011 Fax 810 664 8181 TOOLS Description Source Part No Alcohol Content Tester For testing alcohol content 96 in reformulated oxygenated fuels Kohler 25 455 11 S Ca
105. n oil into a container it should flow freely Check for metal chips and other foreign particles Sludge is a natural by product of combustion a small accumulation is normal Excessive sludge formation could indicate over rich fuel settings weak ignition overextended oil change interval or wrong weight or type of oil was used CLEANING ENGINE A WARNING y Cleaning Solvents can cause severe injury or 4 death Use only in well ventilated areas away from ignition sources Carburetor cleaners and solvents are extremely flammable Follow cleaner manufacturer s warnings and instructions on its proper and safe use Never use gasoline as a cleaning agent After inspecting external condition of engine clean engine thoroughly before disassembly Clean individual components as engine is disassembled Only clean parts can be accurately inspected and gauged for wear or damage There are many commercially available cleaners that will quickly remove grease oil and grime from engine parts When such a cleaner is used follow manufacturer s instructions and safety precautions carefully Make sure all traces of cleaner are removed before engine is reassembled and placed into operation Even small amounts of these cleaners can quickly break down lubricating properties of engine oil 24 690 32 Rev A CRANKCASE VACUUM TEST Troubleshooting WARNING Carbon Monoxide can cause se
106. nce Line No specific servicing is required for vacuum line unless operating conditions indicate replacement is required All components are serviced individually Abrasion sleeves on hoses should be reused or replaced when servicing vacuum line Please note routing and replicate after service or component replacement to prevent pinching or abrasion of line Only Kohler replacement parts can be used because vacuum line is specific to system and must be maintained Visit KohlerEngines com for recommended Kohler replacement parts Throttle Body Intake Manifold Assembly NOTE ECU Reset is required if throttle body is replaced Throttle body is serviced as an assembly with throttle shaft TPS throttle plate and idle speed adjusting screw installed Throttle shaft rotates on needle bearings non serviceable capped with seals to prevent air leaks 36 KohlerEngines com 24 690 32 Rev A Propane EFI System TROUBLESHOOTING Troubleshooting Guide Condition Possible Cause Engine Starts Hard or Fails to Start When Cold Engine Starts Hard or Fails to Start When Hot Engine Stalls or Idles Roughly cold or warm Engine Misses Hesitates or Stalls Under Load Lock off not functioning Faulty spark plugs Incorrect fuel Incorrect fuel pressure Crankshaft position sensor loose or faulty TPS set incorrect ECU Reset and TPS Learn TPS faulty Engine temp sensor faulty Faulty coils
107. nding on fuel quality operating environment and system performance fuel deposits can accumulate inside regulator Perform following steps to remove any accumulated deposits 1 Turn supply valve off run engine out of fuel and turn off ignition switch 2 Disconnect and ground spark plug leads 3 Remove brass plug from bottom of regulator and drain any accumulated deposits 4 Inspect O ring on plug replace if damaged 5 Reinstall plug and tighten securely Replace 30 Micron Button Filter Remove inlet fitting w O ring button filter and gasket Discard filter gasket and O Ring Position new gasket into regulator install button filter large end in Install new O ring on inlet fitting Reinstall inlet fitting and torque to 20 N m 177 in Ib Lock Off Assembly 1 Disconnect plug from lock off Remove nut and lock off Remove lock off valve body and plunger Discard all parts 2 Install plunger then lock off valve body Torque body to 20 N m 177 in Ib 3 Install lock off assembly and nut Torque nut to 6 5 N m 57 in Ib 4 Reconnect plug to lock off High Pressure Fuel Line High pressure fuel line is mounted to intake manifold No specific servicing is required unless operating conditions indicate that it needs replacement Thoroughly clean area around all joints and relieve any pressure before starting any disassembly Detach by removing two mounting screws wire ties and injector retaining clips Vacuum Refere
108. of closure plate or crankcase 3 Apply a 1 5 mm 1 16 in bead of sealant to sealing surface of closure plate 4 Make sure end of governor cross shaft is lying against bottom of cylinder 1 inside crankcase 5 Install closure plate to crankcase Carefully seat camshaft and crankshaft into their mating bearings Rotate crankshaft slightly to help engage oil pump and governor gear meshes 6 Install screws securing closure plate to crankcase Torque fasteners to 24 4 N m 216 in Ib following sequence On some engines one mounting screw is plated Plated screw is typically installed in hole location 6 Install Stator and Backing Plate 1 Apply pipe sealant with Teflon Loctite 592 PST Thread Sealant or equivalent to stator mounting holes 2 Position stator aligning mounting holes so that leads are at bottom towards crankcase 3 Install and torque screws to 6 2 N m 55 in Ib for new holes or 4 0 N m 35 in Ib for used holes 4 Route stator leads in crankcase channel then install backing plate Secure with screws Torque screws 10 7 N m 95 in Ib for new holes or 7 3 N m 65 in Ib for used holes Install Flywheel A CAUTION Damaging Crankshaft and Flywheel Can cause personal injury Jo CN Sealant Pattern and Torque Sequence Using improper procedures can lead to broken fragments Broken fragments could be thrown from engine Always observe and
109. oke Hold engine in this position while testing Holding tool supplied with tester can be used if PTO end of crankshaft is accessible Lock holding tool onto crankshaft Install a 3 8 in breaker bar into hole slot of holding tool so it is perpendicular to both holding tool and crankshaft PTO If flywheel end is more accessible use a breaker bar and socket on flywheel nut screw to hold it in position An assistant may be needed to hold breaker bar during testing If engine is mounted in a piece of equipment it may be possible to hold it by clamping or wedging a driven component Just be certain that engine cannot rotate off of TDC in either direction 4 Install adapter into spark plug hole but do not attach it to tester at this time 5 Turn regulator knob completely counterclockwise 6 Connectan air source of at least 50 psi to tester 7 Turn regulator knob clockwise increase direction until gauge needle is in yellow set area at low end of scale 8 Connect tester quick connect to adapter hose While firmly holding engine at TDC gradually open tester valve Note gauge reading and listen for escaping air at combustion air intake exhaust outlet and crankcase breather Condition Conclusion Air escaping from crankcase breather Ring or cylinder worn Air escaping from exhaust system Defective exhaust valve improper seating Air escaping from intake Defective intake valve improper seating Gauge reading in low green zone
110. ole 2 D Hole 3 Hole 4 Governor sensitivity is adjusted by repositioning governor spring in holes of governor lever If speed surging occurs with a change in engine load governor is set too sensitive If a big drop in speed occurs when normal load is applied governor should be set for greater sensitivity Adjust as follows 1 To increase sensitivity move spring closer to governor lever pivot point 2 To decrease sensitivity move spring away from 24 690 32 Rev A governor lever pivot point It is recommended engine be operated on a stand or bench prior to installation in piece of eguipment 1 Start engine inspect for leaks and check to make certain that oil pressure 20 psi or more is present Run engine at idle for 2 3 minutes then 5 6 minutes more between idle and midrange Adjust idle speed screw located on throttle body as necessary Standard idle speed setting for EFI engines is 1500 RPM but certain applications might reguire a different setting Adjust high speed stop as necessary located on control panel if eguipped Make sure maximum engine speed does not exceed 4200 RPM no load KohlerEngines com 87 1P24 690 32 30912 2015 by Kohler Co All rights reserved 8 85612 88 KohlerEngines com 24 690 32 Rev A 9
111. oles m 65 in Ib into used holes zz Oil Temperature Sensor into breather cover 7 3 N m 65 in Ib Oil Drain Plug 13 6 N m 10 ft Ib Cylinder Head Hex Flange Nut torgue in 2 increments first to 16 9 N m 150 in lb finally to 33 9 N m 300 in Ib Rocker Arm Screw 11 9 N m 105 in Ib Fan Flywheel Flywheel Retaining Screw 71 6 N m 52 8 ft Ib Metal Debris Screen Fastener to flywheel 9 9 N m 88 in Ib Fuel Vaporizer Regulator Lock Off Regulator to Bracket Nut Regulator Bracket Mounting Screw 19 8 N m 175 in Ib 11 9 N m 105 in Ib Lock Off Valve Body Nut 6 5 N m 57 in Ib Lock Off Valve Body Fuel Outlet Fitting Mounting Screws 20 N m 177 in lb 2 9 N m 26 in Ib Fuel Inlet Fitting 20 N m 177 in lb Coil Fastener Governor Lever Nut 7 1 N m 63 in Ib Ignition Spark Plug 27 N m 20 ft Ib 10 2 N m 90 in Ib Crankshaft Position Sensor Screw 6 2 N m 55 in Ib Crankshaft Position Sensor Bracket Screw Electronic Control Unit Screw 7 3 N m 65 in Ib 6 2 N m 55 in Ib Rectifier Regulator Ground Strap Fastener 2 8 N m 25 in Ib into new holes 2 3 N m 20 in Ib into used holes Rectifier Regulator Fastener 1 4 N m 12 6 in Ib Intake Manifold Fastener torque in 2 increments Manifold Absolute Pressure MAP Sensor Fastener first to
112. ollow these guidelines can burn out starter motor NOTE If engine develops sufficient speed to disengage starter but does not keep running a false start engine rotation must be allowed to come to a complete stop before attempting to restart engine If starter is engaged while flywheel is rotating starter pinion and flywheel ring gear may clash and damage starter NOTE If starter does not crank engine shut off starter immediately Do not make further attempts to start engine until condition is corrected NOTE Do not drop starter or strike starter frame Doing so can damage starter Engines in this series use solenoid shift starters Troubleshooting Starting Difficulties Condition Possible Cause Conclusion Starter does not energize Battery Check specific gravity of battery If low recharge or replace battery as necessary Wiring Clean corroded connections and tighten loose connections Replace wires in poor condition and with frayed or broken insulation Starter Switch By pass switch or solenoid with a jumper wire If starter cranks or Solenoid normally replace faulty components Remove and perform individual solenoid test procedure Starter energizes but turns Battery Check specific gravity of battery If low recharge or replace slowly battery as necessary Brushes Check for excessively dirty or worn brushes and commutator Clean using a coarse cloth not emery cloth Replace brushes if excessively
113. ond pause HEME LE ME Me ee ae E 0 id One second pause 3 3 MMM 7 Three second pause ae ie He Le Hee 6 One second pause Xt 1 Fault Code End Code 61 Diagnostic Fault Code Summary Fault Code Connection or Failure Description 0031 Oxygen Sensor Heater Circuit High Voltage 0032 Oxygen Sensor Heater Circuit Low Voltage 0107 Manifold Absolute Pressure Sensor Circuit Low Voltage or Open 0108 Manifold Absolute Pressure Sensor Circuit High Voltage 0112 Intake Air Temperature Sensor Circuit Low Voltage 0113 Intake Air Temperature Sensor Circuit High Voltage or Open 0117 Coolant Oil Temperature Sensor Circuit Low Voltage 0118 Coolant Oil Temperature Sensor Circuit High Voltage or Open 0122 Throttle Position Sensor Circuit Low Voltage or Open 0123 Throttle Position Sensor Circuit High Voltage 0131 Oxygen Sensor 1 Circuit Low Voltage or Open 0132 Oxygen Sensor 1 Circuit High Voltage 0171 Maximum Adaptation Limit Exceeded 0172 Minimum Adaptation Limit Exceeded 38 KohlerEngines com 24 690 32 Rev A Propane EFI System 0174 Lean Fuel Condition at High Load Open Loop or Insufficient Fuel Supply 0201 Injector 1 Circuit Malfunction 0202 Injector 2 Circuit Malfunction 0230 Fuel Lock off Circuit Low Voltage or Open 0232 Fuel Lock off Circuit High Voltage 0336 Crankshaft Position Sensor Noisy Signal 0337 Crankshaft Posi
114. onization Any service to ECU or TPS Throttle Body including idle speed increase over 300 RPM should include ECU Reset This will clear all trouble codes all closed loop learned offsets all max values and all timers besides permanent hour meter This system will NOT reset when battery is disconnected ECU Reset Procedure 1 Turn key ignition OFF 2 Install Red wire jumper from Kohler EFI service kit on to service port connect white wire to black wire in 4 way diagnostic port 3 Turn key ignition ON then OFF and count 10 seconds 4 Turn key ignition ON then OFF and count to 10 seconds a second time 5 Remove Red wire jumper Turn key ignition ON then OFF and count to 10 seconds a third time ECU is reset ATPS Learn Procedure must be performed after ECU Reset 24 690 32 Rev A Propane EFI System TPS Learn Procedure 1 Turn idle screw clockwise one full turn prior to key ignition ON after ECU Reset 2 Start engine run at low idle until engine is warm 3 Idle speed must be above 1500 RPM If below 1500 RPM turn idle screw up to 1700 RPM and then shut down engine and perform ECU Reset again 4 Adjust idle speed down to 1500 RPM Allow engine to dwell at 1500 RPM for about 3 seconds 5 After this adjust idle speed to final specified speed setting 6 Turn key ignition OFF and count to 10 seconds Learn procedure is complete KohlerEngines com 27 Propane EFI System 10j99Uu09 ans
115. opper 59207 Kohler 25 597 07 S Loctite 59109 Loctite Ultra Black 598 Loctite Ultra Blue 5877 Spline Drive Lubricant Kohler 25 357 12 S 24 690 32 Rev A KohlerEngines com 15 Tools and Aids FLYWHEEL HOLDING TOOL ROCKER ARM CRANKSHAFT TOOL A flywheel holding tool can be made out of an old junk A spanner wrench to lift rocker arms or turn crankshaft flywheel ring gear and used in place of a strap wrench may be made out of an old junk connecting rod 1 Using an abrasive cut off wheel cut out a six tooth 1 Find a used connecting rod from a 10 HP or larger 2 3 16 segment of ring gear as shown Grind off any burrs or sharp edges engine Remove and discard rod cap 2 Remove studs of a Posi Lock rod or grind off Invert segment and place it between ignition bosses cu i steps of a Command rod so joint surface is on crankcase so tool teeth engage flywheel ring CR gear teeth Bosses will lock tool and flywheel in 3 Finda 1 in long capscrew with correct thread size to position for loosening tightening or removing with a match threads in connecting rod puller 4 Use a flat washer with correct LD to slip on capscrew and approximately 1 in O D Assemble capscrew and washer to joint surface of rod KohlerEngines com 24 690 32 Rev A TROUBLESHOOTING GUIDE Troubleshooting When troubles occur be sure to check simple causes which at first may seem too obvious to be
116. or connectors at Black 7 ECU Related e ECU to harness connection problem Code 0032 Component Oxygen Sensor Heater Fault O2S Heater Circuit Low Voltage Condition System voltage too low open connection or faulty sensor Conclusion Engine Wiring Harness Related e Pin circuit wiring or connectors ECU black pin 7 or broken wire Oxygen Sensor Related e Sensor connector or wiring problem Poor system ground from ECU to engine or battery to engine KohlerEngines com 39 Propane EFI System Code 0107 Code 0113 Component Manifold Absolute Pressure Sensor Component Intake Air Temperature Sensor Fault MAP Circuit Low Voltage or Open Fault Intake Air Temperature Sensor Circuit Condition Intake manifold leak open connection or High Voltage or Open faulty sensor Condition Shorted connection faulty sensor broken Conclusion MAP Sensor Related wire or connection e Sensor malfunction Conclusion Temperature Sensor Related e Vacuum leaks from loose manifold or e Sensor wiring or connection sensor Engine Wiring Harness Related Wire Harness Related e Pin circuits ECU Black pin 10 and 8 e Poor grounding or open circuit may be damaged e Wire harness and connectors loose e ECU to harness connection problem or damaged or corroded broken wire e Pin circuit wiring or connectors at Black 10 1
117. or continuity measured Stator leads are shorted to ground replace To test charging system for battery continuously charging at high rate 1 With engine running at 3600 RPM measure voltage from B lead to ground using a DC voltmeter Condition Conclusion Voltage is 14 7 volts or less Charging system is OK Battery is unable to hold charge service or replace Voltage is more than 14 7 volts Faulty rectifier regulator replace KohlerEngines com 24 690 32 Rev A FUSES This engine has 3 blade type automotive fuses Replacement fuses must have same rating as blown fuse Use fuse chart below to determine correct fuse Wire Color Fuse Rating 2 Purple Wires 30 amp Fuse 1 Red Wire w Black Stripe 1 Red Wire w White Stripe 10 amp Fuse 2 Red Wires 10 amp Fuse Fuse Replacement 1 Shut engine off and remove key Locate fuse holders 2 3 Remove fuse cover and pull out fuse 4 Inspect fuse for a solid fusible link or a broken fusible link Replace fuse if fusible link is broken If you are not sure if fusible link is broken replace fuse 5 Insert fuse into fuse holder until it is seated properly Install fuse cover 24 690 32 Rev A KohlerEngines com Electrical System 53 Starter System NOTE Do not crank engine continuously for more than 10 seconds Allow a 60 second cool down period between starting attempts Failure to f
118. ormal operation may continue A technician can access stored fault code using a blink code diagnosis flashed out through MIL An optional computer software diagnostic program is also available see Tools and Aids ECU requires a minimum of 6 0 volts to operate To prevent engine over speed and possible failure a rev limiting feature is programmed into ECU If maximum RPM limit 4500 is exceeded ECU suppresses injection signals cutting off fuel flow This process repeats itself in rapid succession limiting operation to preset maximum Wiring harness used in EFI system connects electrical components providing current and ground paths for system to operate All input and output signaling occurs through two special all weather connectors that attach and lock to ECU Connectors are Black and Grey and keyed differently to prevent being attached to ECU incorrectly Condition of wiring connectors and terminal connections is essential to system function and performance Corrosion moisture and poor connections are as likely cause of operating problems and system errors as an actual component Refer to Electrical System for additional information EFI system is a 12 VDC negative ground system designed to operate down to a minimum of 6 0 volts If system voltage drops below this level operation of voltage sensitive components such as ECU lock off valve ignition coils and injectors will be intermittent or disrupted causing erratic oper
119. ouBeiq JOSUSS eJnje1eduus JOSU9S Josues eJnssa9Jgd JOSU9S diy exeyul IV oimesodua io PV aynjosaypioyuew 9V uonsogemoig dV 9 esueD xo av JOSU9S uonsog yeusyuerg QV Z 1100 uoniuf ov L lO uoniuf av CH 10 99fu jen 3 vy L Joyoalu on z JOD UU0O3 Aale A J0 99UUO M9e g X esnJ VOL M TW A UDJIMS 9JnSS9Jg IO n E HO 4907 JOJO JOUPIS L 10 99Uu09 jeulwweal 9 S poyeinbayjiazuode Y apeg o osnJ Yoe d JoyeinBay saynooy e 10 2 S N yoelg W Kai 1 SUM M uel f Mud I ejdung H enig eq 9 usa19 eq E used 4417 3 MOJISA a SHUM PSY 2 xoe g pes a pou Vv lo e ezi Dav BE W OWWGADWA OG W 8608 a CS CS EE od eu of O 000000 OJO 8I ehre gh 6 ee a oat 40 99UU09 euruiuos 9 WesbeIg BUM LI ssouJep BuuiM 24 690 32 Rev A KohlerEngines com co N Propane EFI System J0j2euuo2 onsouBeiq fv JOSUSS eJnjejeduus JOSU9S Josueg eJinssa9Jgd JOSU9S diy exeju Iv eunjeJeduje WO HV e amp njsqvpiojuew OV uonisog y L dV Josueg usB XO av JOSU9S uonisog yeusyueJl av ZK 1100 uoniuB ov L 1100 uoniu av ZK 10 2efu jen vy L Jojosluj jen z JOj08UU09 a19 A JOjD9UU09 yoe g X esnJ voL M TW A UJJIMS 9JnsS9Jg IO n HO 4907 JOJO JOWeIS L JoyoouUOD jeuuus
120. ous odor is detected ventilate area and contact an authorized service technician Propane is extremely flammable and is heavier than air and tends to settle in low areas where a spark or flame could ignite gas Do not start or operate this engine in a poorly ventilated area where leaking gas could accumulate and endanger safety of persons in area To ensure personal safety installation and repair of propane fuel supply systems must be performed only by qualified propane system technicians Improperly installed and maintained propane equipment could cause fuel supply system or other components to malfunction causing gas leaks Observe federal state and local laws governing propane fuel storage and systems 1 Relieve fuel pressure at lock off Shut off tank valve If possible run engine in a well ventilated area until fuel system is empty and engine stops If unable to run engine work in a well ventilated area and carefully loosen inlet fuel fitting on vaporizer regulator slowly venting off fuel from line When fuel is dispensed retighten fitting and remove quick connect fitting to allow fuel to escape from line Disconnect Spark Plug Leads NOTE Pull on boot only to prevent damage to spark plug lead Disconnect leads from spark plugs Drain Oil from Crankcase and Remove Oil Filter NOTE Some models are equipped with an oil drain valve 1 Remove oil fill cap dipstick and 1 oil drain plug
121. ower for tester being used Turn on power switch POWER light should be illuminated and one of four status lights may be lit as well This does not represent condition of part 5 Press TEST button until a click is heard and then release Momentarily one of four status lights will illuminate indicating partial condition of part 24 690 32 Rev A KohlerEngines com 51 Electrical System Condition Conclusion 20 25 amp OK green light comes on and stays steady Disconnect tester black lead attached to 1 AC terminal and reconnect it to other AC terminal Repeat test If OK green light comes on again part is good and may be used an inadequate ground lead connection Make certain connection location is clean and clamp is Secure Other lights come on Troubleshooting Guide NOTE Aflashing LOW light can also occur as a result of Rectifier regulator is faulty and should not be used 20 25 Amp Battery Charging System NOTE Always zero ohmmeter on each scale before testing to ensure accurate readings Voltage tests should be made with engine running at 3600 RPM no load Battery must be good and fully charged When problems occur in keeping battery charged or battery charges at too high a rate problem can usually be found somewhere in charging system or with battery To test charging system for no charge to battery 1 Insert an ammeter in B lead from rectifier regulator With engine running at 360
122. ows 1 Disconnect spark plug lead s 2 Disconnect negative battery cable from battery Before disconnecting negative ground cable make sure all switches are OFF If ON a spark will occur at ground cable terminal which could cause an explosion if hydrogen gas or propane fuel vapors are present External Engine Components AE o E cos Oil Filter Nipple Air Temperature Throttle Body E Oil Cooler Oil Cooler O Ring G Sensor Assembly l Barrel Baffle ee E Valley Baffle Oil Sentry M Dipstick Tube Dipstick o Breather Cover Breather Cover Gasket Q Ignition Coil SE st 5 de Intake Manifold U MAP Sensor e ine ao W Fuel Quick Connect Debris Screen 58 KohlerEngines com 24 690 32 Rev A Clean all parts thoroughly as engine is disassembled Only clean parts can be accurately inspected and gauged for wear or damage There are many commercially available cleaners that will quickly remove grease oil and grime from engine parts When such a cleaner is used follow manufacturer s instructions and safety precautions carefully Make sure all traces of cleaner are removed before engine is reassembled and placed into operation Even small amounts of these cleaners can quickly break down lubricating properties of engine oil Shut off Fuel Supply Empty System WARNING Explosive Fuel can cause fires and severe Lh burns If a gase
123. per Element 1 Clean area around element Remove wing nut element cover and paper element with precleaner 2 Separate precleaner from element service precleaner and replace paper element 3 Check condition of rubber seal and replace if necessary 4 Install new paper element on base install precleaner over paper element reinstall element cover and secure with wing nut Reinstall air cleaner cover and secure with knob Heavy Duty 1 Unhook retaining clips and remove end cap s 2 Check and clean inlet screen if equipped 3 Pull air cleaner element out of housing and replace Check condition of inner element replace when dirty 4 Check all parts for wear cracks or damage and that ejector area is clean 5 Install new element s 6 Reinstall end cap s with dust ejector valve screen down secure with retaining clips BREATHER TUBE Ensure sure both ends of breather tube are properly connected AIR COOLING A WARNING zt Hot Parts can cause severe burns k Do not touch engine while operating or just after stopping Never operate engine with heat shields or guards removed Proper cooling is essential To prevent over heating clean screens cooling fins and other external surfaces of engine Avoid spraying water at wiring harness or any electrical components Refer to Maintenance Schedule KohlerEngines com 21 Propane EFI System WARNING Explosive Fue
124. pistons Never use old rings Some important points to remember when servicing piston rings 1 Cylinder bore must be deglazed before service ring sets are used 2 If cylinder bore does not need reboring and if old piston is within wear limits and free of score or scuff marks old piston may be reused 3 Remove old rings and clean up grooves Never reuse old rings 4 Before installing new rings on piston place top 2 rings each in turn in its running area in cylinder bore and check end gap Compare ring gap to tolerance listed in Specifications 5 After installing new compression top and middle rings on piston check piston to ring side clearance Compare clearance to tolerance listed in Specifications If side clearance is greater than specified a new piston must be used 70 KohlerEngines com Install New Piston Rings Piston Ring Orientation Top Oil Ring Rail Bottom Oil Ring Rail A Gap B Gap Intermediate Ring D Oil Ring Expander Gap Gap Top Ring Gap FLY Stamp NOTE Rings must be installed correctly Ring installation instructions are usually included with new ring sets Follow instructions carefully Use a piston ring expander to install rings Install bottom oil control ring first and top compression ring last To install new piston rings proceed as follows 1 Oil control ring bottom groove Install expander and then rails Make sure ends of expander are no
125. porizer regulator of accumulated fuel deposits Fuel System e Replace spark plugs and set gap Electrical System Every 500 Hours or Annually e Inspect lock off assembly for damage leakage Fuel System e Have combustion deposits removed if using non synthetic oil Every 600 Hours or Annually e Replace heavy duty air cleaner inner element Air Cleaner Intake Every 1500 Hours e Have vaporizer regulator tested Fuel System Perform these procedures more frequently under severe dusty dirty conditions Must be performed by a Kohler authorized dealer or qualified propane personnel only REPAIRS SERVICE PARTS Kohler genuine service parts can be purchased from Kohler authorized dealers To find a local Kohler authorized dealer visit KohlerEngines com or call 1 800 544 2444 U S and Canada 24 690 32 Rev A KohlerEngines com 3 Maintenance OIL RECOMMENDATIONS Synthetic oil is recommended for use in propane fueled engines Non synthetic oil must be low ash rated oil Oils including synthetic must meet API American Petroleum Institute service class SG SH SJ or SL Select viscosity based on air temperature at time of operation as shown in table below Low ash is defined as less than 196 sulfated ash F 20 0 20 32 40 50 60 80 100 PC 30 20 10 0 10 20 30 40 FUEL RECOMMENDATIONS A WARNING Explosive F
126. pring caps e ntake and exhaust valve mark position e Valve stem seals intake and exhaust 4 Repeat above procedure for other cylinder head Do not interchange parts from one cylinder head to other 24 690 32 Rev A Inspection and Service Valve Details Disassembly Inspection and Service EXHAUST VALVE Sw INTAKE VALVE pe Sie 7 EXHAUST INSERT LA DPA INTAKE INSERT B Dimension Intake Exhaust A Seat Angle 89 89 B Insert O D 36 987 37 013 mm 1 4562 1 4572 in 32 987 33 013 mm 1 2987 1 2997 in C Guide Depth 4 mm 0 1575 in 6 5 mm 0 2559 in D Guide I D 7 038 7 058 mm 0 2771 0 2779 in 7 038 7 058 mm 0 2771 0 2779 in E Valve Head Diameter 33 37 33 63 mm 1 3138 1 3240 in 29 37 29 63 mm 1 1563 1 1665 in F Valve Face Angle 45 45 G Valve Margin Min 1 5 mm 0 0591 in 1 5 mm 0 0591 in H Valve Stem Diameter 6 982 7 000 mm 0 2749 0 2756 in 6 970 6 988 mm 0 2744 0 2751 in After cleaning check flatness of cylinder head and corresponding top surface of crankcase using a surface plate or piece of glass and feeler gauge as shown Maximum allowable out of flatness is 0 01 mm 0 004 in Carefully inspect valve mechanism parts Inspect valve springs and related hardware for excessive wear or distortion Check valves and valve seat area or inserts for evidence of deep pitting cracks or distortion Check clearance of valve stems in guid
127. r high fuel pressure Leaking injector Wiring shorted to voltage Repair wiring Open circuit no activity from sensor Broken element Broken wire Sensor dropped Hard blow to engine or exhaust system Defective sensor Thermal shock Replace sensor Slow time response Open heater circuit Improper handling Carbon deposits Replace sensor Incorrect or contaminated fuel Use high quality fuel Excessive engine oil consumption causing exhaust contamination or other exhaust side contamination Correct engine condition Heater circuit open shorted or out of specification Repair short in harness wires replace sensor Manifold Absolute Pressure Sensor MAP A sealed non serviceable assembly A faulty sensor must be replaced If a blink code indicates a problem with manifold absolute pressure sensor it can be tested as follows 1 Make sure all connections are making proper contact and are free of dirt and debris Remove blower housing Slide locking tab out and pull off manifold absolute pressure connector Turn key Switch to ON and check with a volt meter by contacting red lead to pin 1 and black lead to pin 2 There should be 5 volts present indicating ECU and wiring harness are functioning 24 690 32 Rev A 2 Check continuity in wire harness Ohms between Pin 3 at sensor connector and Black pin 11 connector at ECU should be near zero ohms If no
128. removable but can be reamed 0 25 mm 0 010 in oversize Valves with 0 25 mm oversize stems must then be used If guides are within limits but valve stems are worn beyond limits install new valves Valve Seat Inserts Hardened steel alloy intake and exhaust valve seat inserts are press fitted into cylinder head Inserts are not replaceable but can be reconditioned if not too badly pitted or distorted If cracked or badly warped cylinder head should be replaced Recondition valve seat inserts following instructions provided with valve seat cutter being used Final cut should be made with an 89 cutter as specified for valve seat angle Cutting proper 45 valve face angle as specified and proper valve seat angle 44 5 half of full 89 angle will achieve desired 0 5 1 0 full cut interference angle where maximum pressure occurs on outside diameters of valve face and seat Lapping Valves NOTE Exhaust valves that are black in color cannot be ground and do not require lapping Reground or new valves must be lapped in to provide proper fit Use a hand valve grinder with a suction cup for final lapping Lightly coat valve face with a fine grade of grinding compound then rotate valve on its seat with grinder Continue grinding until a smooth surface is obtained on seat and on valve face Thoroughly clean cylinder head in soap and hot water to remove all traces of grinding compound After drying cylinder head apply a light coating of SAE
129. rings and brushes Individual component available Starter Brush Holding Tool Solenoid Shift Kohler 25 761 20 S Kohler 25 761 41 S Design Technology Inc DTI 031 DTI 033 Kohler 25 761 40 S SE Tools KLR 82411 SE Tools KLR 82416 Triad OHC Timing Tool Set For holding cam gears and crankshaft in timed position while installing timing belt Kohler 28 761 01 S Valve Guide Reamer K and M Series For properly sizing valve guides after installation Design Technology Inc DTI K828 Valve Guide Reamer O S Command Series For reaming worn valve guides to accept replacement oversize valves Can be used in low speed drill press or with handle below for hand reaming Reamer Handle For hand reaming using Kohler 25 455 12 S reamer AIDS Description Kohler 25 455 12 S Design Technology Inc 8 Source Part No Camshaft Lubricant Valspar ZZ613 Kohler 25 357 14 S Dielectric Grease GE Novaguard G661 Kohler 25 357 11 S Dielectric Grease Loctite 51360 Kohler Electric Starter Drive Lubricant Inertia Drive Kohler 52 357 01 S Kohler Electric Starter Drive Lubricant Solenoid Shift Kohler 52 357 02 S RTV Silicone Sealant Loctite 59009 Heavy Body in 4 oz aerosol dispenser Only oxime based oil resistant RTV sealants such as those listed are approved for use Loctite Nos 5900 or 5910 are recommended for best sealing characteristics Loctite Ultra C
130. rvice technician Vap orizer Regulator Lock Off Assembly A Vacuum Line B Vaporizer Regulator C Inlet Fitting D Lock Off Assembly E Outlet Fitting F Oetiker Clamp G Propane Fuel Filter H Bracket 5 84 Connect fuel line quick connect on high pressure fuel line assembly to straight fitting in fuel line after propane fuel filter Apply pipe sealant with Teflon Loctite 592 PST Thread Sealant or equivalent to regulator bracket screws after first 3 4 lead in threads Install screws and secure regulator bracket to crankcase Torque screws to 11 9 N m 105 in Ib With nut installed on center back of vaporizer regulator position regulator so nut comes through key hole slot in bracket installing vaporizer regulator keeping fuel lines propane fuel filter assembled to bracket Torque nut to 19 8 N m 175 in Ib Connect vacuum line to barb on front of vaporizer regulator Reconnect electrical plug to lock off assembly If any Oetiker clamps were cut during disassembly slide a new Oetiker clamp onto fuel line and connect fuel line Only use an Oetiker clamp pliers to crimp Oetiker clamps Oetiker clamp crimp must point up away from top of vaporizer regulator or propane fuel filter and abrasion sleeve must be positioned over Oetiker clamp KohlerEngines com 24 690 32 Rev A Reassembly Install External Governor Controls
131. s nicks or any visible damage If any parts are worn or damaged replace oil pump assembly and or O ring Check oil pickup screen for damage or restriction replace if necessary Reassembly 1 Lubricate outer gerotor gear with oil Install outer gerotor gear through shaft of oil pump around inner gerotor gear Matching molding dots on inner and outer gerotor gears is not necessary and will not affect oil pump efficiency 2 Reinstall ball then spring into pressure relief hole in closure plate Reinstall O ring into groove in closure plate make sure it is fully seated in groove 4 Install oil pump inserting center shaft into corresponding recess in closure plate Apply consistent downward pressure to oil pump cover compressing oil pressure relief spring and start screws Secure oil pump by torquing screws in no specific sequence to 7 9 N m 70 in Ib 5 After torquing rotate gear and check for freedom of movement Make sure there is no binding If binding occurs loosen screws reposition pump retorque screws and recheck movement e Crankcase Components B A Closure Plate Seal B Closure Plate C Oil Pickup Tube D Oil Pump Assembly E Ball F Spring G o P ana H Outer Gerotor Gear l Governor Shaft J Governor Washer K Governor Gear L Governor Cup M Camshaft N Crankshaft o Connecting Rod P Piston 68 KohlerEngines com 24 690 32 Rev A Disassembly Inspection and Service
132. s ECU is not reset During certain operating periods such as cold starts warm up acceleration high load etc a richer air fuel ratio is required and system operates in an open loop mode In open loop operation oxygen sensor output is used to ensure engine is running rich and controlling adjustments are based on primary sensor signals and programmed maps only This system operates open loop whenever three conditions for closed loop operation above are not being met ECU is brain or central processing computer of entire EFI system During operation sensors continuously gather data which is relayed through wiring harness to input circuits within ECU Signals to ECU include ignition on off crankshaft position and speed RPM throttle position oil temperature intake air temperature exhaust oxygen levels manifold absolute pressure and battery voltage 24 690 32 Rev A ECU compares input signals to programmed maps in its memory to determine appropriate fuel and spark requirements for immediate operating conditions ECU then sends output signals to set injector duration and ignition timing ECU continually performs a diagnostic check of itself each of sensors and system performance If a fault is detected ECU can turn on a Malfunction Indicator Light MIL if equipped on equipment control panel store fault code in its fault memory and go into a default operating mode Depending on significance or severity of fault n
133. s securing sensor to mounting bracket and replace sensor b If resistance in step 5 was incorrect but resistance of sensor alone was correct test wire harness circuits between sensor connector terminals and corresponding pin terminals 4 and 13 in main connector Correct any observed problem reconnect sensor and perform step 5 again 7 When fault is corrected and engine starts clear fault codes following ECU Reset procedure Throttle Position Sensor TPS P Resistance Table Throttle Between Resistance mE Position Terminal Value Q Continuity Closed A amp C 1400 1800 Yes Full with Stop Pin A amp C 3200 4100 Yes Full without Stop Pin A amp C 4600 5200 Yes Any A amp B 3000 7000 Yes TPS is a sealed non serviceable assembly If diagnosis indicates a bad sensor complete replacement is necessary If a blink code indicates a problem with TPS it can be tested as follows 1 Counting number of turns back out idle speed adjusting screw counterclockwise until throttle plates can be closed completely Write this number down for reference later 2 Disconnect Black connector from ECU but leave TPS mounted to throttle body 3 a Use an ohmmeter and connect red positive ohmmeter lead to Black pin 12 terminal and black negative ohmmeter lead to Black pin 10 terminal to test 30 KohlerEngines com b Hold throttle closed and check resistance It should be 1400 1800 O
134. sor circuit resistance between Black pin 10 and 8 pin terminals Value should be 3100 3900 O 5 Unplug sensor from wire harness and check sensor resistance separately across two pins Resistance value should again be 3100 3900 O a If resistance is out of specifications replace temperature sensor b If itis within specifications proceed to Step 6 6 Check circuits input ground from main harness connector to sensor plug for continuity damage etc Connect one ohmmeter lead to Black pin 8 in main harness connector as in step 4 Connect other lead to terminal 1 in sensor plug Continuity should be indicated Repeat test between Black pin 10 and terminal 2 in sensor plug Oxygen Sensor O Components 24 690 32 Rev A Propane EFI System Cutaway Oxygen Sensor Components 0 Planar Element A Protection Shield B and Heater Stainless Steel C Lower Insulator D Housing E Upper Insulator F Tu G High Temp Water Seal Temperature must be controlled very accurately and gas constituents measured to a high degree of accuracy for absolute sensor measurements This requires laboratory equipment to determine a good or bad sensor in field Furthermore as with most devices intermittent problems are difficult to diagnose Still with a good understanding of system and sensor it is possible to diagnose many sensor problems in field Using diagnostic software connected to ECU is
135. ssure fuel line meeting a minimum of SAE R7 standard must be installed on Kohler Co engines equipped with propane EFI system from vaporizer regulator to injectors OPERATION NOTE When performing voltage or continuity tests avoid putting excessive pressure on or against connector pins Flat pin probes are recommended for testing to avoid spreading or bending terminals EFI system is designed to provide peak engine performance with optimum fuel efficiency and lowest possible emissions Ignition and injection functions are electronically controlled monitored and continually corrected during operation to maintain ideal air fuel ratio Central component of system is Engine Control Unit ECU which manages system operation determining best combination of fuel mixture and ignition timing for current operating conditions 22 KohlerEngines com Fuel is delivered from tank to integrated lock off valve at tank pressure Fuel travels to vaporizer regulator which reduces pressure to 24 26 psi typical Fuel then passes through a fine high pressure filter is delivered from vaporizer regulator through high pressure fuel line into injectors which inject fuel into intake ports ECU controls amount of fuel by varying length of time that injectors are on This can range from 2 to over 12 milliseconds depending on fuel requirements Controlled injection of fuel occurs every other crankshaft revolution or once for each 4 stroke cycle When
136. stem pressure from leakage can cause hot restart problems and longer cranking times To check for leakage it will be necessary to loosen or remove blower housing which may involve removing engine from unit Refer to Disassembly for removal of injector 1 Remove manifold mounting bolts and separate throttle body manifold from engine leaving TPS high pressure fuel line injectors and fuel line connections intact Discard old gaskets 2 Turn key switch ON to activate energize lock off valve and pressurize system Do not turn switch to START position Use soapy water to detect gaseous fuel leaks 3 If either injector exhibits leakage of more than two to four drops per minute from tip or shows any sign of leakage around outer shell turn ignition switch OFF and replace injector as follows 4 Depressurize fuel system 5 Clean any dirt accumulation from sealing mounting area of faulty injector s and disconnect electrical connector s 6 Pull retaining clip off top of injector s Remove screw holding injector s from manifold 7 Reverse appropriate procedures to install new injector s and reassemble engine Use new O rings and retaining clips any time an injector is removed new replacement injectors include new O rings and retaining clips Lubricate O rings lightly with clean engine oil Use installation tool provided with O rings to install new upper O ring Place tool into fuel injector inlet Place one side of O ring into O
137. system pressure of 26 psi 3 is observed wiring lock off and regulator are working properly Turn key switch OFF and observe system pressure System pressure should not drop more than 5 psi per minute If it does drop more that this a leak may be present in system and should be investigated If system pressure is OK depress valve button on tester to relieve system pressure a If pressure is too high or too low replace regulator 3 Iflock off did not activate step 2 disconnect plug from lock off Connect a DC voltmeter across terminals in plug turn on key switch and observe if a minimum of 7 volts is present during six second prime process 4 fno voltage is observed connect red lead of meter to red wire of plug and black lead to a good ground while key is still ON 5 f voltage is between 7 and 14 turn key switch OFF and connect an ohmmeter between terminals on lock off to check for continuity a If there was no continuity between lock off terminals replace lock off valve b If voltage was below 7 test wiring harness and battery 6 If voltage at plug was good and there was continuity across lock off terminals reconnect plug to lock off making sure you have a good connection Turn on key switch and listen for lock off to activate a If lock off clicks repeat steps 1 and 2 to verify correct pressure b If lock off still does not operate replace it Regulator Maintenance Drain Accumulated Deposits Over time depe
138. t overlapped 2 Middle compression ring center groove Install center ring using a piston ring installation tool Make sure identification mark is up or colored dye stripe if contained is to left of end gap 3 Top compression ring top groove Install top ring using a piston ring expander Make sure identification mark is up or colored dye stripe if contained is to left of end gap 24 690 32 Rev A Connecting Rods Offset stepped cap connecting rods are used in all these engines Inspection and Service Check bearing area big end for excessive wear score marks running and side clearances refer to Specifications Replace rod and cap if scored or excessively worn Service replacement connecting rods are available in STD crankpin size and 0 25 mm 0 010 in undersize 0 25 mm 0 010 in undersized rod can be identified by drilled hole located in lower end of rod shank Always refer to appropriate parts information to ensure correct replacements are used Remove Crankshaft Carefully pull crankshaft from crankcase Inspection and Service Crankshaft Components and Details Self Tapping Screw Flat Washer C Plug D Crankshaft A Fillet Must Blend Smoothly with Bearing Journal Surface High Point from Fillet Intersections 45 Minimum IJO T m This Fillet Area Must Be Completely Smooth 24 690 32 Rev A Disassembly Inspection and Service
139. t with cylinder wall Use of a commercial cutting cooling agent is recommended 2 With lower edge of each stone positioned even with lowest edge of bore start drill and honing process Move hone up and down while resizing to prevent formation of cutting ridges Check size frequently 3 When bore is within 0 064 mm 0 0025 in of desired size remove coarse stones and replace them with burnishing stones Continue with burnishing stones until bore is within 0 013 mm 0 0005 in of desired size and then use finish stones 220 280 grit and polish bore to its final size A crosshatch should be observed if honing is done correctly Crosshatch should intersect at approximately 23 33 off horizontal Too flat an angle could cause rings to skip and wear excessively and too steep an angle will result in high oil consumption 4 After resizing check bore for roundness taper and size Use an inside micrometer telescoping gauge or bore gauge to take measurements These measurements should be taken at 3 locations in cylinder at top middle and bottom Two measurements should be taken perpendicular to each other at each location 24 690 32 Rev A Clean Cylinder Bore After Honing Proper cleaning of cylinder walls following boring and or honing is very critical to a successful overhaul Machining grit left in cylinder bore can destroy an engine in less than 1 hour of operation after a rebuild Final cleaning operation should a
140. te f e Circuit providing voltage or ground to Component Oxygen Sensor TPS damaged Fault O28 1 Circuit High Voltage e TPS signal input circuit damaged Condition _ Shorted connection or faulty sensor Conclusion Oxygen Sensor Related Code 0123 e Sensor connector or wiring problem Component Throttle Position Sensor TPS e Sensor contaminated or damaged e e Poor ground path Fault TPS Circuit High Voltage e Pin circuit wiring or connectors Condition Shorted connection or faulty sensor ECU Black pin 10 or Black pin 17 Conclusion TPS Sensor Related m e Sensor connector or wiring Engine Wiring Harness Related dirt grease oil wear voltage and actual sensor voltage e Sensor loose on throttle body manifold e Short in wire harness Throttle Body Related e Throttle shaft or bearings worn damaged Engine Wiring Harness Related e ECU pins Black 10 12 and 16 damaged wiring connectors e ECU pins Black 10 12 and 16 routed near noisy electrical signal coils alternator e Intermittent 5 volt source from ECU pin Black 16 e ECU to harness connection problem 24 690 32 Rev A KohlerEngines com 41 Propane EFI System Code 0171 Code 0172 Component Fuel System Component Fuel System Fault Maximum adaptation limit exceeded Fault Minimum adaptation limit exceeded Condition Fuel filters plugged low pressure at Condition Too high pressure
141. th engine oil Compress rings using a piston ring compressor Make sure FLY stamping on piston is facing towards flywheel side of engine Use a hammer with a rubber grip and gently tap piston into cylinder as shown Be careful that oil ring rails do not spring free between bottom of ring compressor and top of cylinder Install inner rod cap to connecting rod using screws Two different types of connecting rod screws have been used If 6 mm straight shank torgue in increments to 11 6 N m 103 in Ib If 6 mm straight shank gray metallic color it is not necessary to lubricate this screw torque in increments to 13 6 N m 120 in Ib Illustrated instructions are provided in service rod package Repeat above procedure for other connecting rod and piston assembly Install Governor Cross Shaft 1 2 Lubricate governor cross shaft bearing surfaces in crankcase with engine oil Slide small lower washer onto governor cross shaft and install cross shaft from inside of crankcase Install nylon washer onto governor cross shaft then start push on retaining ring Hold cross shaft up in position place a 0 50 mm 0 020 in feeler gauge on top of nylon washer and push retaining ring down shaft to secure Remove feeler gauge which will have established proper end play Install Camshaft 1 Liberally apply camshaft lubricant to each of cam lobes Lubricate camshaft bearing surfaces of crankcase and camshaft with engine o
142. tion Sensor No Signal 0351 Cylinder 1 Ignition Coil Malfunction 0352 Cylinder 2 Ignition Coil Malfunction 0562 System Voltage Low 0563 System Voltage High 61 End of Code Transmission ECU continuously monitors engine operation against preset performance limits If operation is outside limits ECU activates MIL if equipped and stores a diagnostic code in its fault memory If component or system returns to proper function ECU will turn off MIL If MIL stays illuminated it warns customer a fault is currently happening and dealer service is required Upon receipt dealer technician can access fault code s to help determine what portion of system is malfunctioning Codes are accessed through key switch and displayed as blinks or flashes of MIL Access codes as follows 1 2 3 Check that battery voltage is above 11 volts Start with key switch OFF Turn key switch to ON and OFF then ON and OFF then ON leaving it on in third sequence Do not start engine Time between sequences must be less than 2 5 seconds MIL will blink a series of times Number of times MIL blinks represents a number in blink code A sequence of four digits make up a fault code There is a one 1 second pause between blinks of a fault code There is a three 3 second pause between separate fault codes After fault code s are blinked a two digit 61 is blinked to indicate program has completed a It s a good idea to write down codes as they
143. ttery WARNING Ro Rotating Parts can cause severe injury Stay away while engine is in operation Keep hands feet hair and clothing away from all moving parts to prevent injury Never operate engine with covers shrouds or guards removed WARNING P Hot Parts can cause severe burns ANN poni wit Do not touch engine while operating or just after stopping WARNING High Pressure Fluids can puncture skin and cause severe injury or death J Do not work on fuel system without proper training or safety equipment Never operate engine with heat shields or guards removed Fluid puncture injuries are highly toxic and hazardous If an injury occurs seek immediate medical attention A WARNING Cleaning Solvents can cause severe injury or death Use only in well ventilated areas away from ignition sources A cauTION Failure to utilize or reassemble debris screen as designed could Cr result in debris screen e failure and serious personal injury 4 Carburetor cleaners and solvents are extremely flammable Follow cleaner manufacturer s warnings and instructions on its proper and safe use Never use gasoline as a cleaning agent N KohlerEngines com 24 690 32 Rev A MAINTENANCE INSTRUCTIONS Maintenance A E WARNING e Disconnect and ground spark plug
144. ue screws to 9 9 N m 88 in Ib 4 Connect breather separator hose to top of throttle body using a pliers to compress spring clip Route hose through housing by pressing hose into cutout of blower housing Position abrasion sleeve 5 Push electrical connector onto intake air temperature sensor making sure a good connection is made by listening for a click 6 Connect 5 32 in LD vent hose to bottom of throttle body Other end of vent hose connects to vaporizer regulator 7 Push electrical connector onto throttle position sensor making sure a good connection is made KohlerEngines com 83 Re Inst assembly all Vaporizer Regulator Lock Off endanger safety of persons in area Explosive Fuel can cause fires and severe To ensure personal safety installation and repair of propane LA 4 A If a gaseous odor is detected ventilate area A WARNING Propane is extremely flammable and is heavier than air and tends to settle in low areas where a spark or flame could ignite gas Do not start or operate this engine in a poorly ventilated area where leaking gas could accumulate and burns fuel supply systems must be performed only by qualified propane system technicians Improperly installed and maintained propane equipment could cause fuel supply system or other components to malfunction causing gas leaks Observe federal state and local laws governing propane fuel storage and systems and contact an authorized se
145. uel can cause fires and severe burns LA 4 4 If a gaseous odor is detected ventilate area and contact an authorized service technician Propane is extremely flammable and is heavier than air and tends to settle in low areas where a spark or flame could ignite gas Do not start or operate this engine in a poorly ventilated area where leaking gas could accumulate and endanger safety of persons in area To ensure personal safety installation and repair of propane fuel supply systems must be performed only by qualified propane system technicians Improperly installed and maintained propane equipment could cause fuel supply system or other components to malfunction causing gas leaks Observe federal state and local laws governing propane fuel storage and systems This engine is certified to operate on commercial propane per GPA STD 2140 If you have any questions contact your propane supplier Propane from an appropriate propane fuel tank supplied separately is required to operate this engine KohlerEngines com STORAGE If engine will be out of service for 2 months or more follow procedure below 1 Change oil while engine is still warm from operation Remove spark plug s and pour about 1 oz of engine oil into cylinder s Replace spark plug s and crank engine slowly to distribute oil 2 Disconnect negative battery cable 3 Separate propane tank from unit and store separately in an area
146. unds e ECU e Vehicle safety interlocks ground signal on safety wire Diagnostic Aid 7 FUEL SYSTEM ELECTRICAL no fuel delivery Condition e No fuel e Air in high pressure fuel line e Fuel valve shut OFF e Fuel filter line plugged e Injector circuit s pin circuits Black 5 and Black 6 e Injector e ECU grounds e ECU Diagnostic Aid 8 FUEL SYSTEM fuel pressure Low Fuel Pressure Condition e Low fuel insufficient fuel supply e Fuel filter plugged e Fuel supply line plugged Low Fuel Pressure Condition e Pressure regulator not functioning properly Diagnostic Aid 9 BASIC ENGINE cranks but will not run Condition e Refer to basic engine troubleshooting charts within Troubleshooting Electronic Fuel Injection System and Electrical Systems KohlerEngines com 45 Propane EFI System EFI Diagnostic Flow Diagram START OF TEST PROCEED TO START OF TEST FOR RETEST KEY ON MALFUNCTION INDICATOR LIGHT NO REFER TO DIAGNOSTIC AID 1 SYSTEM POWER REFER TO DIAGNOSTIC FAULT CODE SUMMARY CLEAR CODES REFER TO DIAGNOSTIC AID 3 RUN ON ARE FAULT CODES PRESENT DOES ENGINE START YES NO NO YES OPERATE AT VARIOUS SPEED LOAD CONDITIONS xn i REFER TO DIAGNOSTIC m ARE FAULT CODES FAULT CODE SUMMARY ij YES S NO KEY OFF AND KEY ON NO CLEAR AES i LISTEN FOR FUEL LOCK OFF e 8 E D DOES LOCK OFF ACTIVATI N OFF ARTE REFER TO DIAGN
147. uring closest connecting rod end cap Remove end cap 2 Carefully remove connecting rod and piston assembly from cylinder bore 3 Repeat above procedure for other connecting rod and piston assembly 4 Remove piston pin from piston for inspection Use a small screwdriver to pry pin retainer out of groove Inspection Piston and Rings Components and Details Top Compression A Piston B Ring Middle Compression C Ring D Rails Oil Control Ring E Expander F 3 Piece Scuffing and scoring of pistons and cylinder walls occurs when internal engine temperatures approach welding point of piston Temperatures high enough to do this are created by friction which is usually attributed to improper lubrication and or overheating of engine Normally very little wear takes place in piston boss piston pin area If original piston and connecting rod can be reused after new rings are installed original pin can also be reused but new piston pin retainers are required Piston pin is included as part of piston assembly if pin boss in piston or pin are worn or damaged a new piston assembly is required Ring failure is usually indicated by excessive oil consumption and blue exhaust smoke When rings fail oil is allowed to enter combustion chamber where it is burned along with fuel High oil consumption can also occur when piston ring end gap is incorrect because ring cannot properly conform to cylinder wall
148. urrounded by exhaust gas with inner portion exposed to ambient air When oxygen concentration on one side of tip is different than that of other side a voltage signal up to 1 0 volt is generated and sent to ECU Voltage signal tells ECU if engine is straying from ideal fuel mixture and ECU then adjusts injector pulse accordingly Oxygen sensor functions after being heated to a minimum of 400 C 752 F A heater inside sensor heats electrode to optimum temperature in about 10 seconds Oxygen sensor receives ground through wire eliminating need for proper grounding through muffler If problems indicate a bad oxygen sensor check all connections and wire harness Oxygen sensor can also be contaminated by leaded fuel certain RTV and or other silicone compounds fuel injector cleaners etc Use only those products indicated as O2 Sensor Safe Manifold absolute pressure MAP sensor provides immediate manifold pressure information to ECU MAP measures difference in pressure between outside atmosphere and vacuum level inside intake manifold and monitors pressure in manifold as primary means of detecting load Data is used to calculate air density and determine engine s mass air flow rate which in turn determines required ideal fueling MAP also stores instant barometric pressure reading when key is turned ON Fuel injectors mount into intake manifold and high pressure fuel line attaches to them at top end Replaceable O rings on both ends
149. vere nausea fainting or death Avoid inhaling exhaust fumes WARNING Rotating Parts can cause severe injury Stay away while engine is in operation Engine exhaust gases contain poisonous carbon monoxide Carbon monoxide is odorless colorless and can cause death if inhaled Keep hands feet hair and clothing away from all moving parts to prevent injury Never operate engine with covers shrouds or guards removed A partial vacuum should be present in crankcase when engine is operating Pressure in crankcase normally caused by a clogged or improperly assembled breather can cause oil to be forced out at oil seals gaskets or other available spots Crankcase vacuum is best measured with either a water manometer or a vacuum gauge Complete instructions are provided in kits To test crankcase vacuum with manometer 1 Insert rubber stopper into oil fill hole Be sure pinch clamp is installed on hose and use tapered adapters to connect hose between stopper and one manometer tube Leave other tube open to atmosphere Check that water level in manometer is at 0 line Make sure pinch clamp is closed 2 Start engine and run no load high speed 3 Open clamp and note water level in tube Level in engine side should be a minimum of 10 2 cm 4 in above level in open side If level in engine side is less than specified low no vacuum or level in engine side is lower than level in open side
150. x Out of Round Limit Max Taper 0 120 mm 0 0047 in 0 05 mm 0 0020 in Cylinder Head Max Out of Flatness Governor 0 01 mm 0 004 in Governor Cross Shaft to Crankcase Running Clearance 0 025 0 126 mm 0 0009 0 0049 in Cross Shaft O D New Max Wear Limit Governor Gear Shaft to Governor Gear Running Clearance 7 949 8 000 mm 0 3129 0 3149 in 7 936 mm 0 3124 in 0 090 0 160 mm 0 0035 0 0063 in Gear Shaft O D New Max Wear Limit 5 990 6 000 mm 0 2358 0 2362 in 5 977 mm 0 2353 in Ignition Spark Plug Gap Crankshaft Position Sensor Air Gap Piston Piston Rings and Piston Pin Piston to Piston Pin Running Clearance 0 76 mm 0 030 in 0 2 0 7 mm 0 008 0 027 in 0 006 0 017 mm 0 0002 0 0007 in Max Wear Limit Pin Bore I D New 17 006 17 012 mm 0 6695 0 6698 in Max Wear Limit 17 025 mm 0 6703 in Pin O D New 16 995 17 000 mm 0 6691 0 6693 in 16 994 mm 0 6691 in Top Compression Ring to Groove Side Clearance 0 030 0 070 mm 0 001 0 0026 in Middle Compression Ring to Groove Side Clearance 0 030 0 070 mm 0 001 0 0026 in Oil Control Ring to Groove Side Clearance 0 060 0 190 mm 0 0022 0 0073 in Top Compression Ring End Gap New Bore 0 189 0 277 mm 0 0074 0 0109 in Used Bore Max 0 531 mm 0 0209 in Center Compression Ring End Gap New Bore 1 519 1 797

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