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Group 14 - Fuel System

1. mmt m n One Step Lean Two Steps Lean eet stt t tg Choke Unloader Idle Mixture Screws Turns Open Idle Speed RPM Curb Idle Fast Idle Speed RPM Engine Displacement cu in MRNA tints as tt n n Dn esr rt n n rn n n ng n 5 Downdraft 383 R 4371A 1 9 16 1 13 32 63 65 62 64 61 63 9 16 1 4 Travel 7 drill 200 28 drill 35 drill 5 64 11 64 1 1 2 650 1700 Well Thermostatic Coil Spring 2 Notches Rich CARTER AVS SERIES CARBURETORS Transmission Type Engine Displacement Cu In THROTTLE BORE Primary eee nn n Secondary MAIN VENTURI Primary eec Ir etre MAIN JET Primary Secondary LOW SPEED JET enar c c c 9 n Standard 6 ADJUSTMENTS Accelerator Pump top of plunger to air horn orbe Een Fast Idle Cam Position drill size Choke Unloader Vacuum Kick drill size Bow Vent Valve Setting Fast Idle Speed Idle Speed r p m Secondary Throttle Lever Adj
2. 65 Fast Idle Speed On Vehicle 14 GENERAL INFORMATION The Ball and Ball dual throat 1 1 2 inch Carburetor Model C A S Cleaner Air System BBD 4725S BBD 47268 and BBD 4894S are used on the 383 cu in En gines when the vehicles are equipped with manual or automatic transmissions respectively Fig 1 BBD 47265 is used only on vehicles without air condition ing while BBD 4894S is used only on vehicles with air conditioning This carburetor is equipped with a hot idle compensator valve which is a thermostatically operated air bleed to relieve an overrich condition at idle This condition is the result of excessive heat and resultant overrich mixtures These three carburetors are also equipped with a distributor ground switch which retards the distributor when the carburetor is at curb idle for better emission control The Ball and Ball dual throat 1 1 2 inch carburetor models E C S Evaporation Control System BBD 4727S and BBD 4728S are used on the 383 cu in en gines when the vehicles are equipped with manual and automatic transmissions respectively Fig 2 Both A of these carburetors are equipped with a hot idle com pensator valve which is a thermostatically operated air bleed to relieve an overrich condition at idle This condition is the result of excessive heat and resultant overrich mixtures These two carburetors are also equipped with a distributor ground switch whi
3. CURB IDLE AIR BLEED AG DISCHARGE NY NW gt FORT IDLE TRANSFER AIR BLEED NON ADJUSTABLE IDLE 05 TUBE 7 N MAIN WELL N Y 222 NR556B Fig 5 Idle System ture then flows down another vertical passage At the bottom of this vertical passage the fuel air mixture is metered by an idle limiter screw This adjustment is made at the factory and no field adjustment should be required However if an adjustment is necessary refer to Rough Idle and Low Speed Surge para graph under General Information The mixture then flows through a channel in the throttle body to the curb idle discharge port The fuel is discharged into the throttle bore just below the throttle valve The air that is supplied to the curb idle system is supplied through two idle air bleed restrictions and by a curb idle air bleed adjusting screw This is the only screw used to adjust curb idle mix ture The screw is located near the primary bowl vent on the choke air horn Turning the screw clockwise leans the curb idle mixture counter clockwise enrichens the mixture Primary Idle Transfer System Fig 5 separate off idle system is used in the carburetor to provide fuel air mixture from idle operation until the main system is in full operation Fuel for the idle transfer system enters the well through the main jet and travels up through the idle transfer tube and crosses ove
4. 1 00 1 00 1 00 1 00 1 00 Float Setting at Center ot Floats 5 16 5 16 5 16 5 16 5 16 Vacuum Kick Adjustment 20 28 28 20 28 Fast Idle Cam Position Adjustment 28 28 28 28 28 Bow Vent Valve at curb idle 1 16 1 16 1 16 1 16 1 16 Choke Unloader 1 4 1 4 1 4 1 4 1 4 Idle Speed RPM Curb Idle 750 650 650 750 650 Fast Idle Speed RPM 1700 1700 1700 1700 1700 CHOKE ene eee Well Well Control Thermostatic Thermostatic Coil Spring Coil Spring Setting 2 Notches Rich 2 Notches Rich After Approx 500 Miles If Necessary Without Air Conditioning With Air Conditioning 14 66 SPECIFICATIONS HOLLEY 2210 SERIES 2 BARRELL DOWNDRAFT CARBURETOR Type Manual Transmission Automatic Transmission Bore Venturi Main Metering Jet Standard ADJUSTMENTS Accelerator Pump Setting Tm Float Setting Vacuum Kick Adjustment Fast Idle Cam Position Adjustment Bowl Vent Valve at Curb idle CHOKE TYDE ever ERN After Approx 500 Miles If Necessary 94 5 4 4 4
5. CARBURETOR BOWL VENT N VALVE VENT ACCEL RATOR 2 TO AIR CLEANER SECONDARY TUBE PUMP VENT TUBE LEVER VACUUM HOSE ADJUSTING FITTING FAST IDLE NUT SECONDARY CHOKE CAM CONTROL THROTTLE SHAFT ACCELERATOR PUMP LEVER THROTTLE LEVER DISTRIBUTOR VACUUM ADVANCE TUBE CONNECTION CHOKE SECONDARY DIAPHRAGM LINK CURB IDLE SPEED THROTTLE CONNECTOR ADJUSTING LINK CHOKE SCREW UNLOADER LEVER PY872 Fig 2 Carburetor Assembly E C S SECONDARY IDLE AIR BLEEDS SECONDARY FUEL BOWL ETT TEE SECONDARY HIGH SPEED BLEEDS 8 SECONDARY IDLE AIR BLEEDS BOOSTER VENTURIS PRIMARY IDLE AIR BLEEDS CHOKE DIAPHRAGM CURB IDLE AIR BLEEDS BOWL VENT ROD CURB IDLE AIR BLEEDS PRIMARY HIGH SPEED BLEEDS PRIMARY FUEL BOWL BOWL VENT VALVE NR451B Fig 3 Carburetor Assembly Top View 14 40 D ao TRANSFER TUBE F N i CD 5 FLOAT SHAFT FLOAT FLOAT FUEL INLET NEEDLE AND SEAT BAFFLE NP599B Fig 4 Primary Fuel Inlet System The fuel enters the fuel bowl through a fuel inlet fitting and into the fuel inlet valve The amount of fuel entering the fuel bowl is determined by the space between the top of the movable needle and its seat and also by the pressure from the fuel pump The fuel inlet system must constantly maintain the specified level of fuel as the basic fuel metering sys tems are calibrated to deliver the proper mixture only w
6. Secondary Throttle Lockout Adj Float Setting Float Drop Air Valve Spring Tension from Vertical Turns C A S C A S Carter 4 Barre Downdraft AVS 4736S AVS 4732S Automatic Automatic 383 383 1 7 16 1 7 16 1 11 16 1 11 16 1 3 16 1 3 16 089 089 098 098 68 031 68 031 16 546 16 546 7 16 7116 50 50 1 4 1 4 44 44 3 64 3 64 1700 1700 700 700 19 64 19 64 020 020 5 16 5 16 1 2 1 2 2 2 E C S 5 47345 Automatic 383 1 7 16 1 11 16 1 3 16 089 098 68 031 16 546 7116 50 1 4 44 3 4 1700 700 19 64 020 5 16 1 2 2 5 AVS 4737S Manual 440 1 11 16 1 11 16 1 3 16 089 095 365 035 16 617 7116 50 1 4 20 3 64 2000 900 23 164 020 7 32 1 2 2 A SPECIFICATIONS 14 67 CHOKE Well Well Control wes RR RES CUORE Coil Spring Coil Spring Setting rrr rh nn 2 Notches Rich 2 Notches Rich After Approx 500 Miles If Necessary Without Air Conditioning With Air Conditioning CARTER AVS SERIES CARBURETOR C A S C A S E C S E C S uo teer etie ig Carter 4 Barrel Downdraft Model AVS 4738S AVS 4741S AVS 4739S AVS 4740S Transmission Type Automatic Au
7. Since the service procedures are identical on all Carter AVS carburetors the illustrations showing the various disassembly procedures will not always show any one specific carburetor The throttle valves of the secondary half of the carburetor are mechanically connected to the primary valves and open with the primary after an approxi mate 60 lag and continue to open until both primary and secondary throttle valves reach the wide open position simultaneously As engine speed increases the forces exerted by the velocity of intake air down through the venturis of the carburetor increases and A tends to overcome the air valve spring attached to the air valve permitting the air valve to position its self according to engine requirements The AVS air valve secondary carburetor con tains many features some of which are the locations for the step up rods and pistons The step up rods pistons and springs are accessible for service without removing the air horn or the carburetor from the engine The primary venturi assemblies are replace able and contain many of the calibration points for both the high and low speed system One fuel bowl feeds both the primary and secondary nozzles on the right side while the other fuel bow takes care of the primary and secondary nozzles on the left side This provides improved performance in cornering quick stops and acceleration All the major castings of the carburetor are alumi num with t
8. 6 Remove clip from choke operating link and dis engage link from diaphragm plunger stem and choke lever Fig 1 7 Remove vacuum diaphragm and bracket assem bly and place to one side to be cleaned as a special item A liquid cleaner may damage diaphragm ma terial 8 Remove screws that attach idle solenoid bracket and solenoid to air horn and main body Remove sole STEP UP PISTON AND METERING ROD STEP UP PISTON SPRING Reo STEP UP C PISTON ee V STEP up PISTON SPRING SCREW AB COVER PLATE 3 STAGE METERING ROD NR5I3A Fig 2 Removing or Installing Step Up Pistons and Rods A noid assembly from carburetor If so equipped 9 Remove eight screws that attach air horn to main body Lift air horn straight up and away from main body When removing air horn use care so as not to bend or damage floats Remove accelerator pump plunger lower spring from pump cylinder 10 Remove hot idle compensator and gasket if so equipped Disassembling Air Horn Place air horn in an inverted position on bench to protect the floats then proceed to disassemble as fol lows 1 Using a suitable tool remove float fulcrum pins left and right then lift float up and out of bosses on air horn It is suggested that the float on the pump side be marked so that floats can be reinstalled in their respective positions 2 Remove two needle valves from their respective seats after
9. Fig 22 Vacuum Kick Adjustment 5 Reinstall the vacuum hose on the correct car buretor fitting 6 Make the following check With no vacuum ap plied to the diaphragm the CHOKE VALVE SHOULD MOVE FREELY between the open and closed posi tions If movement is not free examine the linkage for misalignment or interferences caused by the bend ing operation Repeat the adjustment if necessary to provide proper link operation Secondary Throttle Adjustment This adjustment no longer required as valves are pre adjusted and need no further adjustment Idle Speed Adjustment Curb Idle Refer to General Information at front of Group Checking Wet Fuel Level On Vehicle Before checking wet fuel level check the fuel pump pressure to be certain 5 pound reading is obtained To check wet fuel level remove lower bolt furthest from fuel supply Primary and Secondary and install C 4051 wet fuel level gauge Fig 23 As screw is be SECONDARY FUEL BOWL WET LEVEL GAUGE SPACER PRIMARY FUEL BOWL TAKE READING ON GRADUATED SCALE NP788B Fig 23 Checking Wet Fuel Level on Vehicle ing removed fuel will be lost Start or crank engine and allow fuel bowls to fill The reading on level gauge should be 9 16 for Primary and 13 16 inch for Sec ondary with 5 pounds fuel pump pressure If an adjustment is necessary remove fuel bowl and FUEL PUMP FUEL SYSTEM 14 55 bend tang on float until correct speci
10. PUMP 7 BOWL VENT VALVE TUBE FITTING THROTTLE GROUND LEVER oz CHOKE SWITCH DIAPHRAGM LINK 3 TERMINAL AIR CLEANER TO CLOSED CARBURETOR CRANKCASE CURD IDEE VENT TUBE BOWL VENT VALVE DISTRIBUTOR VENT TUBE SPEED OPERATING LEVER VACUUM FITTING ADJUSTING ADVANCE SCREW TUBE FITTING FAST IDLE FAST IDLE CHOKE IDLE MIXTURE FAST IDLE CAM CONNECTOR ROD VACUUM ADJUSTING SCREW SPEED DIAPHRAGM LIMITER CAPS ADJUSTING SCREW BOWL VENT VALVE CHOKE UNLOADER TANG OPERATING LEVER BEND TO ADJUST BEND TO ADJUST CARBURETOR ASSEMBLY AVS ECS PY726 Fig 1 Carburetor Assembly 14 28 FUEL SYSTEM AVS pensator valve as described previously Fig 1 The Carter four barrel carburetor models E C S Evaporation Control System AVS 4739S and AVS 4740S are used on the 440 cu in engines when the vehicles are equipped with standard or automatic transmissions respectively These two carburetors are also equipped with a hot idle compensator valve as is AVS 4741S above Fig 1 These five AVS carburetors are equipped with a distributor ground switch which retards the distrib utor when the carburetor is at idle for better emis sion control The idle speed solenoid which is mounted on these carburetors Fig 21 is used to maintain a higher idle speed when the vehicle is running and allows the throttle to close to a low idle speed throttle position when the ignition key is turned off to prevent after running
11. 14 2 With a finger lightly pressing against shaft lev er a slight drag should be felt as drill is being with drawn If an adjustment is necessary bend unloader tang on throttle lever until correct opening has been obtained Fig 15 Use Tool T109 214 Bowl Vent Adjustment E C S 1 Open choke valve so that fast idle cam allows valves to close curb idle 2 Be sure that pump operating rod 15 in long Stroke hole in throttle lever Remove bowl vent valve cover if not previously done 3 Close throttle valves tightly Using a narrow ruler measure the distance from top of bowl vent valve rubber tip to top of air horn casting Fig 16 This measurement should be 5 32 inch 4 If an adjustment is necessary bend bowl vent lift arm using a suitable tool until correct opening has been obtained WARNING DO NOT BEND BOWL VENT VALVE LEAF SPRING DURING BENDING OPERATION OR IMPROPER VENT VALVE OPER ATION WILL RESULT Install bowl vent valve cover and secure with attaching screws 5 On C A S carburetors with the throttle valves closed curb idle there should be 1 16 inch clear ance between bowl vent valve and seat on air horn Fig 16 When measured at outermost or largest dimension with a drill shank 6 If an adjustment is necessary bend vent valve lifter arm until correct clearance has been obtained Idle Speed Adjustment Curb Idle Refer to General Information at Front of Section BEND UNLOADER TANG
12. 5 preron T H A OMS VE 418 POWER VALVE TOOL Fig 7 Removing or Installing Power Valve prying off ends of screws using a suitable tool Be careful not to bend screws Be sure and count num ber of turns to seat the screws as the same number of turns from the seat must be maintained at installa tion Remove screws and springs from metering body Secondary No disassembly required but it is very important that the well bleed parts main metering restrictions and idle feed restrictions are clean Fig 9 Disassembling Secondary Diaphragm 1 Remove the diaphragm cover screws and sepa rate diaphragm cover from housing 2 Remove diaphragm return spring from cover then slide diaphragm out of housing Disassembling Throttle Body CAUTION In normal routine cleaning and overhaul of the carburetor do not remove the throttle valves unless they are nicked or damaged If necessary to remove proceed as follows 1 Remove screws that hold throttle valves to throttle shafts These screws are staked to prevent MAIN METERING BODY PRIMARY p f POWER MAIN METERING JETS NY43C Fig 8 Removing or Installing Main Metering Jets 14 48 FUEL SYSTEM HOLLEY 4160 MAIN WELL WELL FUEL AND AIR IDLE FEED RESTRICTION 5 FUEL 5 Bv WELL WELL BLEED eee NP761A Fig 9 Secondary Metering Body loosening
13. Compress diaphragm and spring to engage arm with pull rod 5 Using suitable drift align rocker arm and wash ers then install pivot pin Install retaining washer then peen pivot pin to retain 6 Place valve body on diaphragm Align then in stall attaching screws Draw down evenly 7 With pump held in vise compress rocker arm to its full travel Hold in this position then tighten screws securely This will prevent tearing diaphragm when pump is operated at full stroke 8 Install pump arm follower spring between rock er arm and housing Be sure spring is seated 9 Test pump as described previously FUEL TANK C A S CLEANER AIR SYSTEM GENERAL INFORMATION The fuel tank on all models except Station Wagon Models is located at the rear of the body under the trunk compartment floor Fig 1 In Station Wagon CAP Q FILLER TUBE MOUNTING CLIP VENT TUBE HOSE models the fuel tank is mounted in the left rear quarter panel beyond the wheel house Fig 2 If the vehicle is to be stored for any appreciable VENT TUBE i 222 amp GROMMET T GROMMET FUEL GAUGE TANK UNIT NK554 C Fig 1 Fuel Tank Mounting 119 5 inch W B Vehicles 14 58 FUEL SYSTEM FUEL TANK STRAP TANK ASSEMBLY STRA CAP ASSEMBLY NRIS Fig 2 Fuel Tank Assembly 121 5 inch W B Vehicles length of time the gasoline should be drained from the entire system in order to
14. FUEL TANK Station Wagon Fig 2 Removal CAUTION Be sure the Ignition Switch is turned OFF before disconnecting or connecting the gauge wire 1 Remove filler cap and syphon fuel into safety can 2 Raise vehicle on hoist and remove fender skirt if so equipped 3 Remove left rear tire and wheel 4 Remove screws that attach stone shield to wheel house Slide shield down and away from vehicle 5 Disconnect fuel line ground strap and gauge wire 6 Place stands under frame at rear to support vehicle as hoist is lowered 7 Remove rear shock absorbers lower attaching nuts then slide off lower pivot FUEL TANK FUEL SYSTEM CLIP FUEL GAUGE GROUNDING 14 59 TUBE FUEL LINE WIRING FUEL GAUGE TANK UNIT lt TUBE FUEL LINE CLIP FUEL GAUGE GROUNDING STUD FUEL GAUGE STUD FUEL GAUGE UNIT TUBE FUEL GAUGE TANK UNIT NR11 Fig 4 Fuel Tank Ground Strap 8 Remove left rear brake drum 9 Remove left rear spring hanger attaching bolts to frame 10 Lower hoist and allow rear axle to fall away from vehicle far enough so as not to stretch brake hose 11 Remove fuel tank support strap nuts from eye bolts 12 Slide fuel tank forward and tilt leading edge down Work fuel tank out from under rear quarter panel 13 Loosen tank gauge unit using spanner wrench Tool C 3582 Slide unit up and out of tank Installation 1 Position fuel tank gauge unit in tank us
15. PUMP DIAPHRAGM CONTACT BUTTON FUEL INLET FITTING ACCELERATOR PUMP INLET PUMP COVER CHECK BALL i ASSEMBLY NOT REMOVABLE ar NS PUMP LEVER PUMP NP762 COVER SCREWS Fig 10 Accelerating Pump Exploded View clamp then install attaching screw and tighten se curely C A S Carburetors Figs 1 or 2 7 On E C S carburetors install seal on bottom of vent valve Slide plastic valve and seal into cover with valve recess mating with shoulder on underside of cover 8 Install bowl vent valve spring in position in opening in bowl then install valve and cover over spring Install attaching screws and tighten securely 9 Install bowl vent operating rod clamp and spring in position on bowl Install attaching screw and tighten securely SECONDARY FUEL BOWL 17 64 DRILL OR GAUGE 15 64 DRILL HOLLEY 4160 FUEL SYSTEM 14 49 GASKET PRIMARY FUEL INLET gt gt a FUEL BOWL SEAT mo FUEL INLET y a NEEDLE FLOAT RETAINER e BAFFLE FLOAT ASSEMBLY NP753 Exploded View Secondary 1 Install new gasket on fuel inlet needle seat Fig 11 then install in fuel bowl Tighten securely Slide fuel inlet needle into seat 2 Install float baffle in position then slide float hinge over pivot and secure with clip Install float spring Adjusting Floats 1 Invert the primary fuel bowl and using a 15 64 inch drill shank or gauge measure the clearance be tween t
16. With air horn inverted upside down place air horn in upright position and measure the distance floats move from inverted to upright position This measurement should be 1 2 inch Fig 10 Air horn gasket installed If an adjustment is necessary bend Stop tabs on float levers until correct drop setting has been obtained Bend tab toward needle seat to lessen drop or away from seat to increase drop 2 After floats have been checked and adjusted continue to assemble carburetor as follows 3 Place accelerator pump plunger lower spring in pump cylinder then lower air horn carefully down on main body Care must be taken to center small brass main bleed tubes so that they wil pass through holes in air horn without being damaged Be sure the fuel baffles on the air horn slide down in front bow side of the float chamber baffles or the air horn will not index correctly with the main body and can cause the floats to hang up Be sure the leather on the plunger does not curl or wrinkle Accelerator pump operation will be affected if this precaution is not observed Place curb idle solenoid in position on carburetor Install attaching screws and tighten securely If so equipped 4 Install air horn attaching screws and tighten securely The change from low speed best fuel economy road load mixtures to richer wide open throttle full power mixtures is now accomplished in two steps This has made it possible to secure best low speed fu
17. Worn or corroded needle valve and seat h Incorrect valve lash i Engine miss ignition j Incorrect timing a Accelerator pump piston or plunger leather too hard worn or loose on stem b ou accelerator pump discharge all c accelerator pump inlet check all d Incorrect fuel or float level e Worn accelerator pump and throttle linkage f Manifold heat valve sticking g No power mixture h Incorrect timing i Incorrect pump setting a Cracked body A screws be turned the same amount on each adjust ment so that as finally set both screws will be the same number of turns from the seated position 7 Install plastic caps over idle screws Correction a Disassemble carburetor Then use compressed air to clear idle bleed after soaking it in a suitable solvent Disassemble carburetor Then use compressed air to clear idle discharge holes after soaking main and throttle bodies in a suitable solvent Disassemble carburetor Check throt tle valve shaft for wear excessive wear is apparent replace throttle body assembly Replace worn or damaged idle needle Adjust air mixture e Test fuel level in carburetor Adjust as necessary to obtain correct float level f Tighten main body to throttle body screws securely to prevent air leaks and cracked housings g Clean and inspect needle valve and seat If found to be in questionable condition replace assemb
18. by excessive choke enrichment can be cleared by use of the unloader Adjust the system as follows 1 Qualify the choke control lever if necessary See Qualifying Choke Control Lever Paragraph 2 Hold the throttle valves in the wide open posi tion Insert the specified drill between the upper edge of the choke valve and the inner wall of the air horn see specifications 3 With a finger lightly pressing against the choke control lever a slight drag should be felt as the drill is being withdrawn If an adjustment is necessary bend the indicated tang until correct opening has been obtained Fig 19 Fast Idle Speed Adjustment On Vehicle Fast idle engine speed is used to overcome cold engine friction stalls after cold starts and stalls be cause of carburetor icing Set this adjustment after the vehicle odometer indicates over 500 miles to in sure a normal engine friction level Prepare tbe en gine by driving at least 5 miles Connect a tachometer and set the curb idle speed and mixture then proceed as follows 1 With the engine off and the transmission in the PARK or NEUTRAL position open the throttle slightly 2 Close choke valve until fast idle screw tang can be positioned on the second highest speed step of the fast idle cam Fig 20 3 Start the engine and determine the stabilized OR DRILL CHOKE VALVE a WALL OF AIR HORN fiel CHOKE CONTROL LEVER THROT
19. 1 To correctly set float height when carburetor is being overhauled install floats with fulerum pin and pin retainer in main body 2 Install rubber tipped needle seat and gasket in body and tighten securely 3 Invert main body so that weight of float only is forcing needle against seat Hold finger against re tainer to fully seat fulcrum pin 4 Using Tool T 109 280 a scale measure float Fig 10 There should be 5 16 inch from surface of fuel bowl to crown of each float at center If an adjustment is necessary hold the floats on bottom of the bowl and bend float lip toward or away from needle Recheck the 5 16 inch setting again and repeat the lip bending operation as required CAUTION When bending the float lip do not allow the lip to push against the needle as the synethetic rubber tip can be compressed sufficiently to cause a false setting which will affect correct level of fuel in the bowl STEP UP RODS MUST MOVE FREELY INTERMEDIATE POWER STAGED MIXTURE STEP NK617 Fig 9 Step Up Rods Freeplay A FULCRUM PIN 2 RETAINER IN A POSITION gt CARBURETOR INVERTED FLOAT GAUGE ONLY WEIGHT OF FLOATS NR384 AGAINST INLET NEEDLE Fig 10 Checking Float Setting After being compressed the tip is very slow to re cover its original shape CAUTION It is very important that the float lip be perpendicular to the needle or slanted not more than ten degrees away from the needle wh
20. 14 Use a 6 inch ruler for this measurement 6 Place a new gasket over primary metering body aligning pin Rear Carefully slide metering body over balance tube and down into position against main body 7 Slide a new gasket over metering body align ment studs and carefully position against body 8 Carefully install primary fuel bowl over balance tube and down against metering body Slide new gas kets over the long fuel bowl mounting screws then install in position through fuel bowl Tighten securely POWER VALVE 381 VACUUM PASSAGE NL SPARK VACUUM PASSAGE i fis SECONDARY IDLE FUEL PASSAGE Fig 13 Main Body Identification Bottom View BALANCE TUBE w 766 2 SECONDARY METERING BODY NP766C ae ER O RING Fig 14 Positioning Balance Tube If new gaskets are not used a fuel leak will develop Be sure and install distributor ground switch lead and lead clamp on long screw adjacent to fuel inlet 9 Slide a new ring on each end of fuel tube then install fuel tube into opening in primary fuel bowl Press in on tube end until seated 10 Carefully slide secondary fuel bowl over bal ance tube and fuel tube and seat against gasket In stall secondary fuel bowl attaching screws after in stalling new gaskets Tighten securely 11 Install accelerating pump discharge needle in the discharge passage in the center of primary ven turi To te
21. Adjustment Curb Idle Refer to General Information at Front of Group Fast Idle Speed Adjustment On Vehicle Fast idle engine speed is used to overcome cold engine friction stalls after cold starts and stalls be cause of carburetor icing Set this adjustment after 14 36 FUEL SYSTEM AVS SECONDARY AIR VALVE WIDE OPEN LOCK SCREW ADJUSTING SLEEVE TURN 2 FULL TURNS FROM WIDE OPEN POSITION PY732 Fig 19 Secondary Air Valve Adjustment vehicle odometer indicates over 500 miles to insure a normal engine friction level Prepare engine by driv ing at least 5 miles Connect a tachometer and set curb idle speed and mixture then proceed as follows 1 With engine off and transmission in PARK or NEUTRAL position open throttle slightly 2 Close choke valve until fast idle screw can be positioned on the second highest speed step of fast idle cam Fig 20 3 Start engine and determine stabilized speed Turn fast idle speed screw in or out to secure specified speed Refer to Specifications 4 Stopping engine between adjustments is not necessary However reposition fast idle speed screw on cam after each speed adjustment to provide cor rect throttle closing torque Before adjusting idle and or fast idle speeds and mixtures make sure that the basic timing is correctly adjusted as outlined under Idle Speed Adjustment Curb Idle FAST IDLE SPEED ADJUSTING SCREW ON SECOND HIGHEST STEP OF CAM FA
22. FUEL GAUGE GROUNDING STUD FUEL GAUGE STUD FUEL GAUGE UNIT TUBE FUEL GAUGE TANK UNIT NR11 Fig 4 Fuel Tank Ground Strap FUEL TANK FUEL SYSTEM 14 63 nuts then slide off lower pivot 8 Remove left rear brake drum 9 Remove left rear spring hanger attaching bolts to frame 10 Lower hoist and allow rear axle to fall away from vehicle far enough so as not to stretch brake hose 11 Remove fuel tank support strap nuts from eye bolts 12 Slide fuel tank forward and tilt leading edge down Work fuel tank out from under rear quarter panel 13 Loosen tank gauge unit using spanner wrench Tool C 3582 Slide unit up and out of tank Installation 1 Position fuel tank gauge unit in tank using a new gasket Tighten securely using Tool C 3582 2 Work fuel tank up into position in quarter panel Move rearward until filler tube is centered in opening in quarter panel Place straps in position and install nuts Tighten to 40 inch pounds Bottom strap should be tightened first 3 Install fuel line and connect ground strap Fig 4 and fuel gauge wire Install new clamps on vent tubes then install tubes on tank fittings Tighten clamps securely 4 Raise hoist far enough to engage spring hanger with frame 5 Position left rear spring hanger at frame and install attaching bolts Tighten to 30 foot pounds 6 Slide shock absorbers over pivots and secure with nuts Tighten to 50 foot pounds 7
23. If either intake check assembly or discharge check needle leaks after above test and service fix attempt to reseat as follows Intake Check Ball Remove the intake check assembly from the throt tle body Install a new check assembly then retest as described previously Fig 4 Discharge Check Needle 1 With discharge check needle installed insert a piece of drill rod down on needle Lightly tap drill rod with a hammer to form a new seat Remove and discard old needle and install a new one Retest as described previously If service fix does not correct the condition a new carburetor will have to be in stalled 2 Install accelerator pump discharge check needle jet housing and gasket Install housing and attaching screws Tighten screws securely 3 Press down on accelerator pump plunger shaft and as plunger is being depressed a clear straight stream should emit from each jet If streams are not identical if either one is diverted or restricted a new accelerator pump jet housing should be installed After test pour gasoline from carburetor bowl and remove pump plunger Assembling Air Horn 1 Slide fuel inlet screen into fuel line fitting then install in air horn Tighten securely 2 Check to see if leather on accelerator pump plunger is hard cracked or worn If any sign of wear or deterioration is evident install a new plunger as sembly Install pump link 3 Place pump arm in position over boss of air hor
24. ON THROTTLE LEVER FIGS 1 OR 2 CHOKE LEVER LIGHT CLOSING 7 PRESSURE AGAINST CHOKE LEVER DRILL OR GAUGE CHOKE VALVE PY504 Fig 14 Checking Choke Unloader Setting BBD FUEL SYSTEM 14 13 UNLOADER TANG ON THROTTLE LEVER PY517 Fig 15 Bending Choke Unloader Tang Measuring Float Setting On Vehicle 1 Remove hairpin clip and disengage accelerator pump rod from throttle lever and pump rocker arm Disconnect automatic choke rod by unsnapping clip 2 Remove air horn attaching screws and lift air horn straight up and away from main body Re move gasket 3 Set float fulcrum pin by pressing a finger against fulcrum pin retainer There should be enough fuel in the bowl to raise floats so that the lip bears firmly against needle Ad ditional fuel may be admitted by slightly depressing BOWL LIFT ARM TOP EDGE ORS AIRHORN CASTING BOWL VENT ADJUSTMENT 5 3 CARBURETORS 1 2M ve PY518 Fig 16 Measuring Bowl Vent Valve Opening C A S 5 14 14 FUEL SYSTEM HOLLEY 2200 float If fuel pressure in the line is insufficient to force additional fuel into bowl add necessary fuel from a clean container WARNING Since the manifold may be hot it is dan gerous to spill fuel onto these surfaces Take the nec essary precautions to avoid spillage 4 With only pressure from buoyant float holding lip against inlet needle chec
25. THE CHOKE FIRMLY BOLTED TO THE MANIFOLD FIRE OR HEAT DAM AGE MAY OCCUR When installing the steel well cup make certain the gasket is in good condition and is in place to prevent exhaust leakage Do not lubricate any of the choke parts or the con trol unit This causes dirt to accumulate and would result in binding of the choke mechanism The choke control unit is accurately adjusted when first assembled Under normal servicing do NOT change the setting or disassemble the control unit If however the setting has been disturbed reset as follows Loosen locknut and turn shaft with screw driver until index mark on disc is in alignment with correct mark on the frame Hold in this position with screwdriver while tightening nut Refer to Specifica tions for indexing All the carburetors referred to in the Fuel System are either equipped for use with a Cleaner Air System C A S or an Evaporation Control System E C S de pending on the area in which the vehicle is to be used The servicing procedures covering these carburetors are nearly identical Differences between the two types of carburetors are covered where applicable in the service procedures CLEANER AIR SYSTEM C A S The cleaner air system consists of a special air cleaner breather cap ventilation valve carburetor distributor and various other automatic control de BOWL VENT VALVE AIR CLEANER CARBURETOR CRANKCASE VENTILATION V
26. adhere to the following in structions 2 Mark position of throttle valves in bores 3 Remove screws that hold throttle valves to shaft and slide valves out of bores These screws are staked on the opposite side and care should be used at removal so as not to break off in the shaft Remove the staked end of the screws with a file 4 Slide throttle shaft and lever out of body 5 Install new throttle shaft and lever 6 Install throttle valves in their respective bores with valve numbers toward manifold Install new Screws but do not tighten Hold valves in place fully closed position with fingers pressing on high sides of valves Tap valves lightly with a screwdriver to seat in throttle bores Partially tighten screws Hold up to a strong light to check for a proper position in bore They may have to be rotated slightly as the valves are eliptical When properly positioned tighten screws securely and stake using pliers 7 Install idle mixture screws and springs in body The tapered portion must be straight and smooth If tapered portion is grooved or ridged a new idle mix ture screw should be installed to insure having cor rect idle mixture control DO NOT USE A SCREW DRIVER Turn screws lightly against their seats with IDLE TRANSFER PORTS SPARK ADVANCE lt THROTTLE VALVES NR382 Fig 7 Ports in Relation to Throttle Valves 14 10 FUEL SYSTEM BBD fingers Back off the number of turns counted at
27. and is necessary to avoid breaking off in shaft Remove staking with a file 2 Slide damaged throttle valves out of bores It should be noted at this time that the secondary throttle valves are thicker than the primary valves Do not install secondary valves in primary bores or visa versa as the relationship of the primary valves to the idle transfer port and spark advance control ports is carefully established for one particular assembly CLEANING CARBURETOR PARTS The recommended solvent for gum deposits is de natured alcohol which is easily obtainable However there are other commercial solvents such as Metal clene which may be used with satisfactory results The choke diaphragm can be damaged by solvents Avoid placing the diaphragm assembly in ANY liquid Clean the external surfaces with a clean cloth or soft wire brush Shake dirt or other foreign material from the stem side of the diaphragm Depressing the dia phragm stem to the retracted position will provide an additional hole for the removal of dirt Compressed air can be used to remove loose dirt but should not be connected to the vacuum inlet fitting IMPORTANT If the commercial solvent or cleaner recommends the use of water as a rinse it should be HOT After rinsing all trace of water must be blown from the passages with air pressure it is fur ther advisable to rinse all parts in clean gasoline or kerosene to be certain no trace of moisture remains N
28. and mixture then proceed as follows 1 With engine off and transmission in PARK or NEUTRAL position open throttle slightly 2 Close choke valve until fast idle screw can be positioned on second highest speed step of fast idle cam Fig 17 3 Start engine and determine stabilized speed Turn fast idle speed screw in or out to secure speci fied speed See Specifications 4 Stopping engine between adjustments is not necessary However reposition fast idle speed screw on cam after each speed adjustment to provide correct throttle closing torque To set the idle speed on vehicles refer to Fuel System General Information Paragraph HOLLEY 2200 SERIES CARBURETOR INDEX Page Page Carburetor Adjustments 24 Vacuum 24 Accelerator Pump 25 Carburetor Systems 14 Bowl Vent 25 Cleaning Carburetor Parts 21 Choke Unloader Wide Open Kick 25 Disassembling Carburetor 18 Fast idle Speed and Cam Position 24 General Information 14 Fast Idle Speed On Vehicle 26 Inspection and Reassembly 21 1 5 2 26 Specifications 66 GENERAL INFORMATION The Holley dual throat 2200 series carburetor mod el C A S Cleaner Air System R 4371A Fig 1
29. as described in the Fast idle Speed Adjustment On the Vehicle Paragraph How FOR ADJUSTMENT 777 BEND ACCELERATOR PUMP ROD BE SURE CURB AT ANGLE IDLE SPEED SCREW 15 BACKED OFF 501 a Fig 11 Checking Accelerator Pump Setting 14 12 FUEL SYSTEM BBD ever the Fast Idle Cam Position Adjustment can be made on the bench This adjustment is important to assure that the speeds of each step of the cam occur at the proper time during engine warm up 1 With fast idle speed adjusting screw contacting second highest speed step on fast idle cam move choke valve toward closed position with light pressure on choke shaft lever 2 Insert specified drill see specifications be tween choke valve and wall of air horn An adjust ment will be necessary if a slight drag is not obtained as drill is being removed 3 If an adjustment is necessary bend fast idle con nector rod at lower angle using Tool T109 213 until correct valve opening has been obtained Fig 12 Vacuum Kick Adjustment This test can be made ON or OFF vehicle The choke diaphragm adjustment controls the fuel delivery while the engine is running It positions the choke valve within the air horn by action of the link age between the choke shaft and the diaphragm The diaphragm must be energized to measure the vacuum kick adjustment Use either a distributor test machine with a vacuum source or vacuum supplied by the vehicle 1 If adju
30. assembly Fig 6 SPECIAL TOOL INTAKE CHECK ASSEMBLY ACCELERATOR PUMP WELL SECONDARY MAIN METERING i PRIMARY 2 INTAKE CHECK ASSEMBLY ap NR515 Fig 4 Removing or Installing Main Metering Jets 14 30 FUEL SYSTEM AVS PRIMARY VENTURI 219 CLUSTER 2 PUMP SIDE PRIMARY VENTURI CLUSTER CHOKE SIDE ATTACHING 47 wer NR516 Fig 5 Removing or Installing Primary Venturi Cluster The valves are milled to give proper port relation If new throttle shafts should be installed in an old worn body it would be very unlikely that the original relationship of these ports to the valves would be ob tained A very slight change in the port relationship to the valves would adversely affect normal carbu retor operation between the speeds of 15 and 30 miles per hour It is recommended that if the throttle shafts are excessively worn that a new carburetor be installed However if the throttle valves have become nicked burred or damaged new valves may be installed pro viding the following instructions are carefully fol lowed The screws that attach the throttle valves are staked on the opposite side and care should be used in removal so as not to break the screws in the throttle shaft Remove the staked portion of the screws with a file Remove the screws that attach the primary throttle valves to the throttle shaft and slide valve or valves out of bores Remov
31. attach primary venturi choke and pump side to main body Lift venturi straight up and away from main body Fig 5 Dis card gaskets The venturi assemblies are not inter AVS FUEL SYSTEM 14 29 S 59 ACCELERATOR PUMP JET HOUSING primey GASKET DISCHARGE PASSAGE VENTURI PRIMARY CLUSTER 7 PUMP Ed 1 CLUSTER INTAKE CHECK BALL ASSEMBLY NR514 Fig 3 Removing or Installing Accelerator Pump Jet Housing changeable side for side and must be reinstalled in their original locations at reassembly 5 Using Tool T 109 59 screw driver bit remove accelerator pump intake check valve located inside fuel bowl adjacent to accelerator pump cylinder 6 Remove plastic limiter caps from idle air mix ture screws Be sure and count number of turns to seat the screws from stop as the same number of turns from seat must be maintained at installation Remove screws and springs from throttle body The carburetor now has been disassembled into two units namely air horn and the main and throttle body casting The component parts of each have been dis assembled as far as necessary for cleaning and in spection It is usually not advisable to remove the throttle shafts or valves unless wear or damage necessitates the installation of new parts During the manufacture of the carburetor the location of the idle transfer ports and the idle discharge ports to the valve is care fully established for one particular
32. body attaching screws Separate bodies and dis card gasket 21 Turn idle limiter caps to stop Top of throttle lever side and bottom of stop on other Remove idle limiter caps by prying off with suitable tool Be care ful not to bend screws Be sure and count number of turns to seat the screws as the same number of turns from the seat must be maintained at installation Re move screws and springs from throttle body The carburetor now has been disassembled into three sub assemblies the air horn main body throttle body and the components of each disassembled as far as necessary for cleaning and inspection Caution In normal routine cleaning and overhaul of the carburetor do not remove throttle valves unless BOWL VENT VALVE OPERATING LEVER STUB ENDS OF SPRING BOWL VENT VALVE SPRING SEC CUP e PY839 Fig 5 Removing or installing Bowl Vent Valve Operating Lever 14 20 FUEL SYSTEM HOLLEY 2200 A AIR HORN FUEL ru BAFFLE GASKET a ia LUGS ACCELERATOR PUMP PLUNGER MAIN WELL TUBES DO NOT BEND FULCRUM PIN CENTERED MAIN BODY ATTACHING SCREW gt PYB 3 VACUUM POWER Fig 9 Removing or Installing Fuel Baffle PISTON STEM PY840 they are nicked or damaged necessary to remove proceed as follows 1 Remove screws that hold throttle valves in throttle shaft These screws are staked to prevent loosening and care is necessary to a
33. cam move choke valve toward closed position with light pressure on choke shaft lever 2 Insert specified drill refer to Specifications be tween choke valve and wall of air horn Fig 12 An adjustment will be necessary if a slight drag is not obtained as the drill is being removed 3 To adjust bend fast idle connector rod at angle using Tool T 109 213 until correct valve opening has been obtained Fig 12 Vacuum Kick Adjustment This test can be made ON or OFF vehicle The choke diaphragm adjustment controls the fuel DRILL OR GAUGE LIGHT CLOSING PRESSURE ON CHOKE LEVER BEND FAST IDLE CONNECTOR ROD AT THIS FAST IDLE SPEED SCREW ON 2ND k HIGHEST STEP OF 7 FAST IDLE SPEED SAC anc ree NR521A ADJUSTING SCREW OF HIGHEST STEP Fig 12 Fast Idle Cam Position Adjustment AVS FUEL SYSTEM 14 33 delivery while the engine is running It positions the choke valve within the air horn by use of the linkage between the choke shaft and the diaphragm The dia phragm must be energized to measure the vacuum kick adjustment Use either a distributor test machine with a vacuum source or vacuum supplied by the vehicle 1 If adjustment is to be made with engine running disconnect fast idle linkage to allow choke to close to kick position with engine at curb idle If auxiliary vacuum source is to be used open throttle valves engine not running and move choke valve to closed position Releas
34. dicates the presence of dirt or a damaged or worn check needle or seat Clean the passage again and re test as above If leakage is still evident attempt to form a new seat as follows 5 With discharge check needle installed insert a piece of drill rod down on needle Lightly tap drill rod with a hammer to form a new seat Remove and dis card old needle and install a new one Retest as de Scribed previously If service fix does not correct the condition a new main body should be installed Re move accelerator pump plunger discharge check needle and fuel from main body 6 Install power valve using Too 109 73 Fig 13 Tighten securely BRASS ROD ACCELERATOR PUMP NO FUEL SHOULD BE EMITTED FROM PASSAGE OR PARTS 50 Fig 16 Testing Accelerator Pump Discharge Check Needle 7 Install main metering jets using Tool TMC 36A Fig 12 Tighten securely Number 65 on throitle lever side and number 63 an other side of bowl 8 Install accelerator pump discharge check needle in pump discharge passage Fig 15 Air Horn 1 Test freeness of choke mechanism in air horn The choke shaft must float free to operate correctly If choke sticks in bearing bores or appears to be gummed from deposits in air horn a thorough clean ing will be required 2 Install vacuum power piston in its cylinder Fig 17 Lock in position by prick punching rim of cylin der at least three places Do not over
35. dis assembly Install new plastic caps with tabs against Stop This screw has a left hand thread Turn counter clockwise Richer and clockwise Leaner Main Body 1 Invert main body and place a new gasket in position and place throttle body on main body and align Install screws and tighten securely 2 Install accelerator pump discharge check ball in discharge passage and check accelerator pump sys tem fuel inlet and discharge check balls as follows 3 Pour clean gasoline into carburetor bowl ap proximately 1 2 inch deep Remove pump plunger from jar of gasoline flex leather several times then slide down into pump cylinder Raise plunger and press lightly on plunger shaft to expel all air from pump passage 4 Using a small clean brass rod hold discharge check ball down firmly on its seat Again raise plung er and press downward No fuel should be emitted from either intake or discharge passage Fig 8 If any fuel does emit from either passage it indi cates the presence of dirt or a damaged check ball seat Check the passage again and repeat test If leak age is still evident install a new check ball The fuel inlet check ball is located at the bottom of the plunger well 5 Install new gaskets on venturi cluster and in stall in position in main body Install cluster screws and tighten securely Test pump discharge by press ing pump plunger down Two fine streams of fuel should be forced from cluster If eit
36. float c High float level d Excessive fuel pump pressure e Worn metering jet a See owner s Manual a Choke thermostat adjustment leaner than specified b Choke thermostat corroded such that it has cracked and distorted lean c Choke linkage shaft or related parts corroded bent or dirty such that sys tem is not entirely free to move from open to closed position d Choke valve improperly seated e Air cleaner interfers with choke shaft or linkage f Air cleaner gasket choke valve or linkage g Spring staging spring distorted or missing interfers with a Engine lubricating oil incorrect vis cosity b Choke thermostat adjustment incor rect rich ENGINE RUNS LEAN FIRST HALF MILE CHOKE LEAN a Review items under Poor Starting b Diaphragm adjustment lean ENGINE RUNS LEAN AFTER HALF MILE ENGINE HEAT INSUFFICIENT a Heat valve stuck open b Heat valve thermostat distorted FUEL SYSTEM 14 5 Correction b Disassemble carburetor Replace de fective gaskets and test for leakage Be sure screws are tightened se curely Test fuel level in carburetor Make necessary adjustment to obtain cor rect float level Clean and inspect needle valve and seat If found to be in a questionable condition replace complete assembly and test fuel pump pressure Refer to Specifications for correct fuel pump pressure Test fuel pump pressure If pressure is in excess
37. float stop Fig 18 The clearance should be 200 inch 1 64 7 drill Be sure drill or gauge is perfectly level when measuring If an adjustment is necessary bent float lip toward or away from needle using a narrow blade screw driver Fig 19 until correct clearance or setting has been obtained 4 Check float drop by holding air horn in an up right position The bottom edge of float should be parallel to underside surface of air horn Fig 20 an adjustment is necessary bend tang on float arm until parallel surfaces have been obtained Installing Air Horn 1 Place a new gasket on air horn then check to be sure main well tubes are straight Lower air horn Straight down on main body guiding accelerator FLOAT STOP AIR HORN INVERTED POT TE DRILL OR GAUGE PY852 Fig 18 Checking Float Setting HOLLEY 2200 FUEL SYSTEM 14 23 FLOAT RAISED m FLOAT ADJUSTING LIP PY853 Fig 19 Bending Float Adjusting Lip pump plunger into its cylinder Caution Do not cut lip of plunger on sharp edge of cylinder Install attaching screws long screw in center and tighten securely Fig 6 2 Install fuel inlet tube fitting and gasket in air horn and tighten securely 3 Engage hooked end of accelerator pump rod in throttle lever hook end toward outside Engage other end of rod in center slot of pump rocker arm Fig 2 4 Install rocker arm on accelerator pump shaft with flats in alignment
38. is used on the 383 cu in engine when the vehicles are equipped with an automatic transmission and without air conditioning only This carburetor is equipped with a distributor ground switch which retards the dis tributor when the carburetor is at curb idle resulting in better emission control Each throat of the carburetor has its own throttle valve and main metering systems and are supple mented by the float accelerating idle and power sys tems CARBURETOR SYSTEMS The carburetor utilizes four basic fuel metering ACCELERATOR PUMP ROCKER ARM ACCELERATOR PUMP ROD BOWL VENT VALVE OPERATING LEVER FAST IDLE CAM FAST IDLE CONNECTOR ROD CHOKE VALVE CARBURETOR AIR CLEANER VENT TUBE FITTING FAST IDLE SPEED ADJUSTING SCREW CURB IDLE ELEVATOR LEGS 4 SPEED ADJUSTING THROTTLE LEVER SCREW DISTRIBUTOR GROUND SWITCH CONNECTOR CRANKCASE VENT TUBE FITTING CHOKE VACUUM DIAPHRAGM CHOKE OPERATING LINK CHOKE LEVER j DISTRIBUTOR 9T VACUUM ADVANCE a TUBE FITTING CRANKCASE VENT TUBE FITTING DISTRIBUTOR GROUND SWITCH CONTACT HOLLEY 2200 FUEL SYSTEM 14 15 CHOKE OPERATING LEVER FAST IDLE CONNECTOR ROD FAST IDLE SPEED ADJUSTING SCREW CURB IDLE SPEED ADJUSTING SCREWS CARBURETOR AIR CLEANER VENT TUBE FITTING 2 VENTURI LONG AIR HORN SCREW BOWL VENT VALVE BOWL VENT E MI OPERATING LEVER ACCELERATOR PUMP SHAFT ACCEL
39. leakage is ex cessive and the assembly must be replaced Install choke diaphragm assembly on the air horn as follows 1 Engage free end of choke operating link in slot of choke lever 2 Install choke diaphragm and mounting bracket on air horn Install attaching screws and tighten se curely 3 Inspect rubber hose for cracks before placing it on correct carburetor fitting Fig 1 after vacuum kick adjustment has been made CARBURETOR ADJUSTMENTS It is very important that the following adjustments are made on a reconditioned carburetor and in the sequence listed Fast Idle Speed and Cam Position Adjustment The fast idle engine speed adjustment should be made on the vehicle as described in the Fast Idle Speed Adjustment On Vehicle paragraph However the Fast Idle Cam Position Adjustment can be made on the bench This adjustment is important to assure that the speeds of each step of the cam occur at the proper time during engine warm up 1 With fast idle speed adjusting screw contacting second highest speed step on the fast idle cam move choke valve toward closed position with light pressure on choke shaft lever 2 Insert specified drill see Specifications between top of choke valve and wall of air horn Fig 21 An adjustment wil be necessary if a slight drag is not obtained as drill shank is being removed 3 If an adjustment is necessary bend fast idle connector rod at angle using Tool T109 213 unti
40. of recommended pres sure refer to Specifications replace fuel pump c d a Remove and clean air cleaner b Disassemble carburetor Replace leaking float Test float level and cor rect as necessary to proper level c Adjust float level as necessary to se cure proper level d Test fuel pump pressure Refer to specifications for recommended pres sure If pressure is in excess of rec ommended pressure replace fuel pump assembly e Disassemble carburetor Replace worn metering jet using a new jet of correct size and type a Instruct owner a Adjust b Replace assembly c Repair clean or replace d Reseat valve e Rotate cleaner to correct position instruct owner f Reinstall gasket properly g Replace or install new spring a Recommend 5W 20 b Adjust to correct setting a See Choke Valve Fails to Close b Readjust to specification a Free with solvent b Replace thermostat 14 6 FUEL SYSTEM BBD Condition Possible Cause Correction c Heat valve failed within exhaust See c Replace heat valve engine section for proper diagnosis d Water temperature subnormal d Check thermostat CARBURETOR a Air leak bypassing the carburetor a Repair MIXTURES LEAN b Carburetor has economy metering b Inform customer system ENGINE RUNS EXCESSIVELY RICH AFTER COLD START CHOKE SYSTEM RICH a Choke thermostat adjustment
41. prevent gum formation the vehicle has been undercoated be sure the fuel tank vent tube under kickup in floor pan is open If this is not done a collapsed fuel tank will result The fuel tank on all models except Station Wagon has a 24 gallon 20 Imperial capacity The Station Wagon capacity is 22 18 1 4 Imperial gallons The filler tube on the conventional models is accessible through the center of the deck opening lower panel while the Station Wagon fills at the left rear upper quarter panel between the quarter post and the fin The fuel tank is fitted with gauge unit including the suction pipe Fig 3 The filter on the end of the suction pipe is replaceable unit and prevents the entry of water and dirt When installing a tank unit be sure the filter is pusbed on the end of the tube until seated SERVICE PROCEDURES REMOVING THE FUEL TANK Except Station Wagon CAUTION Be sure the ignition switch is turned off before disconnecting or connecting the gauge wire Removal 1 Drain tank into a safety can then disconnect fuel line and wire lead to gauge unit 2 Disconnect vent tube at hose connection at leading edge of tank 3 Remove screw that attaches filler tube bracket to rear crossmember 4 Remove nuts that hold ends of fuel tank hold down straps to frame Lower front end of tank far enough to disengage filler tube from rear panel and slide out from under vehicle 5 Remove tank gauge unit using
42. richer a Correct than specified b Choke vacuum diaphragm inoperative b Correct or replace or misadjusted c Choke vacuum passage blocked or c Correct leaking CARBURETOR RICH a Incorrect gasket or gasket installation a Replace or correct between carburetor and intake mani fold EXCESSIVE STALLS AFTER COLD START CHOKE SYSTEM LEAN a Review items under Poor Starting Choke Valve Fails to Close b vacuum diaphragm adjustment b Adjust to Specification ean ENGINE OUTPUT LOW a Fast idle speed low a Adjust to Specification b Fast idle cam position adjustment b Adjust to Specification incorrect c Engine lubrication oil of incorrect c Recommended 5W 20 viscosity d Incorrect timing d Reset timing CARBURETOR LEAN a Curb idle set very lean a Adjust b Air leak bypassing the carburetor b Repair BBD SERIES CARBURETORS 1 INDEX Page Page Automatic Choke well type 1 idle Speed Adjustment 13 Carburetor Adjustments 11 Cleaning Carburetor Parts 1 Accelerator Pump and Bowl Vent 11 13 Closed Crankcase Vent System Engine Group Choke Unloader Wide Open Kick 12 Disassembling Carburetor Choke Vacuum Kick 12 Inspection and Reassembly 9 Fast Idle Cam Position 11 Specifications
43. secure with E clip Slide spring and locknut between fuel pump lever and pump operating lever Open throttle valve and install adjusting screw Tighten 2 or 3 threads to hold The correct setting of the adjusting screw will be covered under adjustments CARBURETOR ADJUSTMENTS It is very important that the following adjustments be made on a reconditioned carburetor Qualifying the Choke Control Lever Choke Unloader Adjustment wide open kick Fast Idle Cam Position Adjustment Vacuum Kick Adjustment On or off vehicle Fast Idle Speed Adjustment On the vehicle Checking the Bowl Vent Valve Clearance Checking the Pump Lever Clearance Idle Speed Adjustment Curb idle Adjusting the Float Secondary Throttle Adjustment Idle Mixture Adjustment Checking Wet Fuel Level Checking Bowl Vent Valve Clearance C A S To check the bowl vent valve clearance Fig 16 proceed as follows 1 With throttle valves at curb idle it should be possible to insert a 1 16 inch drill shank between bowl vent valve and top of primary fuel bowl with the idle speed properly set 2 If an adjustment is necessary bend rod to 14 52 FUEL SYSTEM HOLLEY 4160 change arc of contact with throttle lever using Tool 1109 213 until correct clearance has been obtained Checking Bowl Vent Valve Clearance E C S To check the bowl vent valve clearance adjustment proceed as follows 1 With the throttle valves at curb idle it should be pos
44. spanner wrench Tool C 3582 Fig 3 Check rubber grommet around filler tube If cracked or deteriorated install a new grommet at reassembly Installation Before installing the tank gauge unit check the condition of the filter on the end of suction tube If the filter is plugged install a new filter 1 Position fuel tank gauge unit in tank using a new gasket Tighten securely using Tool C 3582 If tank insulator was torn or damaged during removal of tank be sure and instal a new insulator at re assembly 2 Slide fuel tank under vehicle Raise tank far enough to engage filler spout with opening in rear FUEL SUPPLY TUBE LEAD FUEL GAUGE LOCATING TANGS FILTER SUCTION TUBE p FLOAT NY 1280 Fig 3 Fuel Gauge Tank Unit panel and locator embossments on floor pan 3 Push tank toward rear to fully engage filler Spout in opening 4 Hold fuel tank in this position and place hold down straps in position feeding attaching studs through holes in end of straps Install nuts but do not tighten 5 Guide button head of studs into slots in frame and down into position Tighten hold down strap at taching nuts securely 40 in bs 6 Install filler tube mounting screw and tighten securely 1 Connect vent tubes and hose connections at leading edge of tank 8 Connect lead wire to tank gauge unit recon nect fuel line and ground strap 9 Refill tank and check for leaks
45. tapered portion is grooved or ridged a new idle mixture screw should be installed to insure hav ing correct idle mixture control DO NOT USE A SCREW DRIVER Turn screws lightly against their seats with fingers Back off the number of turns counted at disassembly Install new plastic caps with tabs against stop 2 Slide a new gasket over power valve and install using Tool C 3747 Tighten securely Fig 7 3 Install main metering jets Fig 8 using Tool C 3748 Tighten securely Assembling Fuel Bowls Primary 1 Install accelerator pump spring in position in fuel bowl followed by diaphragm and pump cover When installing diaphragm be sure contact button is toward pump lever in cover Fig 10 2 Place cover over diaphragm with lever on fuel inlet fitting side Fig 10 Install attaching screws and tighten securely 3 Install new gasket on fuel inlet needle seat Fig 11 then install in fuel bowl Tighten securely Slide fuel inlet needle into seat 4 Install float baffle in position then slide float hinge over pivot and secure with clip Install float spring 5 Install new gasket over fuel inlet fitting then install fitting in primary fuel bowl Tighten securely 6 Install bowl vent valve assembly on fuel bowl being sure vent valve spring is hooked into bracket and loop of spring under operating rod Position 4 PRIMARY FUEL AC BOWL p DIAPHRAGM a RETURN SPRING ACCELERATOR
46. the diaphragm may be the cause If pressure is too high main spring is too strong Vacuum Test The vacuum test should be made with the fuel line disconnected from the carburetor This will allow the pump to operate at full capacity which it must do to prime a dry carburetor The minimum reading should be at least 10 inches of vacuum at 500 r p m with the fuel line disconnected at the carburetor NH415B Fig 1 Fuel Pump Assembly 383 and 440 Cu Engine Volume Test 1 The fuel pump should supply 1 quart of fuel in 1 minute or less at 500 r p m Inlet Valve Test To test the inlet valve connect a vacuum gauge on the inlet fitting while the line is disconnected 1 Start engine or turn over with starting motor 2 There should be a noticeable vacuum present not alternated by blowback 3 If blowback is present inlet valve is not seating properly and a new pump should be installed If fuel pump does not perform to above test re quirements fuel pump should be removed from vehicle NR2A Fig 2 Fuel Pump Assembly RD 267A Optional 383 and 440 Cv In Engine Fig 3 Pressure Testing Fuel Pump A DISASSEMBLING FUEL PUMP RD 267A Before disassembly mark housings in such manner that the mark inlet will be facing inlet fuel line when reassembled This is important 1 Grind or file off peened end of pivot pin then drive out pivot pin Remove washer 2 Remove r
47. valve and expels the fuel in the valve housing chamber through the outlet valve to the fuel filter and the carburetor The fuel filter should be changed every 24 000 miles to insure having an unrestricted flow of fuel at all times Do not attempt to clean SERVICE DIAGNOSIS Condition FUEL PUMP LEAKS FUEL FUEL PUMP LEAKS OIL seal b Loose rocker arm pivot pin c Loose pump mounting bolts d Faulty pump to block gasket INSUFFICIENT FUEL DELIVERY tank b Leaks in fuel line or fittings c Dirt or restriction in fuel tank d Worn ruptured or torn diaphragm e Frozen gas lines f Improperly seating valves g Vapor lock h Low pressure i Incorrect fuel pump i Restricted fuel filter FUEL PUMP NOISE a Loose mounting bolts b Scored or worn rocker arm c Weak or broken rocker arm spring Possible Cause a Worn ruptured or torn diaphragm b Loose diaphragm mounting plates c Loose inlet or outlet line fittings Correction a Install new pump b Install new pump c Tighten line fittings a Cracked or deteriorated pull rod oil a Install new pump b Install new pump c Tighten mounting bolts securely d Install new gasket a Vents in tank or filler cap restricted a Install new cap or unplug vents and This will also cause collapsed fuel inspect tank for leaks b Tighten line fittings c Install new fuel filter and clean
48. with light pressure on choke contro lever 3 Insert specified drill between the choke valve and wall of the air horn see specifications An adjustment will be necessary if a slight drag is not obtained as the drill is being removed 4 To adjust bend the indicated tang Fig 21 un til the correct choke valve opening has been obtained Vacuum Kick Adjustment ON or OFF Vehicle The choke diaphragm adjustment controls the fuel delivery while the engine is running It positions the See specifications 14 54 FUEL SYSTEM HOLLEY 4160 DRILL OR ex 477 GAUGE HIGHEST CHOKE VALVE SPEED STEP gt e at a i gt 1 a FAST IDLE SPEED ADJUSTING TANG P cw CE CY 5 AIR HORN CAM POSITION ADJUSTING vs TEAST IDLE CAM i e ALND HIGHEST CHOKE CONTROL SPEED STEP LEVER LIGHT CLOSING PRFSSURE NR454A Fig 21 Fast Idle Cam Position Adjustment choke valve within the air horn by use of linkage be tween the choke shaft and the diaphragm The dia phragm must be energized to measure the vacuum kick adjustment Vacuum can be supplied by a dis tributor test machine another vehicle or vehicle to be adjusted 1 If the adjustment is to be made with the engine running position the fast idle tang Fig 21 Cam position adjustment to aliow choke closure to kick position If auxiliary vacuum source is to be used open throttle valve
49. 4 GROUP 14 FUEL SYSTEM CONTENTS Page Page AVS SERIES CARBURETOR 26 HOLLEY 2200 SERIES CARBURETOR 14 BBD SERIES CARBURETOR 6 HOLLEY 4160 SERIES CARBURETOR 37 FUEL PUMP tes 55 THROTTLE LINKAGE 63 FUEL TANKS 57 SPECIFICATIONS 64 GENERAL INFORMATION SERVICING CARBURETOR Dirt dust water and gummy deposits are some of the main causes for poor carburetor operation How ever proper cleaning and the installation of new parts where required will return the carburetor to its original designed performance When overhauling the carburetor several items of importance should be observed to assure a good job 1 All parts except the choke diaphragm assem bly should be carefully cleaned in a suitable solvent then inspected for damage or wear 2 Use air pressure only to clear the various ori fices and channels 3 Replace questionable parts with NEW ones When checking parts removed from the carburetor it is at times rather difficult to be sure they are satis factory for further service It is therefore recom mended that in such case NEW parts be installed 4 Always use a complete kit when overhauling the carburetor Using the code number stamped on the air horn adjacent to the fuel inlet refer to the parts catalog and order the correct repair kit for the carburetor being worked on CLEANING CARBU
50. 6 Secondary on EE Pa eda 13 16 Accelerator Pump Override Adjustment wide open throttle 015 Min Power Valve stamped 65 ately Well ume Coil Spring SB UTIB epis ce UM 2 Notches Rich SPECIAL TOOLS T109 287 Nr x Ree nen me Elevating Legs 3886 Stand pec vM rh a pn Eum e Y E CAUSE cia Sse wa Bes Rae ete SS Wet Fuel Gauge elc Clutch Head Screwdriver BALL AND BALL 1 2 INCH BBD CARBURETOR C A S C A S C A S E C S 5 Ball and Ball Dual Downdraft Engine Displacement cu in 383 383 383 383 383 Manual Trans BBD 4725S BBD 4727S Automatic Trans 47265 BBD 4894S BBD 4728S D 19 16 1 9 16 1 9 16 1 9 16 1 9 16 Venturi 1 5 16 1 5 16 1 5 16 1 5 16 1 5 16 Main Metering Jet Standard 120 3298 120 3065 120 3065 120 3295 120 3065 One Step Lean 120 3135 120 3045 120 3045 120 3135 120 3045 Two Steps Lean 120 3035 120 3295 120 3295 120 3035 120 3295 Step Up Wire Standard 75 1652 75 1730 75 1730 75 1652 75 1730 Diameter 2 Stage 035 x 027 042 x 039 042 039 035 x 027 042 x 039 ADJUSTMENTS Accelerator Pump Setting
51. ALVE CLEANER TO CAP HOSE BREATHER CAP CRANKCASE 1 STORAGE AREA PY598 Fig 2 Cleaner Air System C A S vices Fig 2 as required The function of the cleaner air system is to reduce the unburned hydro carbons emitted by the vehicle s engine Fresh air is drawn into the air cleaner for con sumption by the engine A portion of this fresh air is diverted through a hose to the breather cap and into the crankcase Manifold vacuum causes crankcase vapors including fresh air and unburned hydro car bons to flow through the crankcase ventilation valve to the base or throttle body of the carburetor These vapors are joined with the fuel mixture in the intake manifold and are delivered into the combustion cham ber from which they are ejected as essentially com pletely burned exhaust products EVAPORATION CONTROL SYSTEM E C S The evaporation control system consists of the C A S system plus a special vented fuel tank sep arator fuel tank vapor tube breather cap enclosed bowl vent valve a vacuum pressure relief fuel tank cap and hoses Fig 3 CARBURETOR AIR CLEANER AIR CLEANER TO BREATHER CAP HOSE Wie Ut VAPOR SEPARATOR at BOWL VENT VALVE HOSE FUEL TANK VAPOR VENT LINE fi NS Y KV BREATHER CAP GAS CAP QN LN 74 BOWL VENT VALVE CRANKCASE 222 FUEL TANK VENTILATION VENT VALVE TO CARBURETOR HOSE VALVE E CRANKCASE VAPOR STORAGE AREA PY599 Fig 3 Evap
52. Clamp Valve Rod 32 Rod Bow Vent Valve 33 Spring Vent Valve Rod 34 Valve Bow Vent 35 Retainer Clip Float 36 Float 37 Spring Float 38 Baffle Float 39 Needle Valve and Seat 40 Screws Fuel Pump Cover 41 Cover Assembly Fuel Pump 42 Diaphragm Fuel Pump 43 Fuel Pump Diaphragm 44 Fitting Fuel Inlet 45 Gasket Fuel Inlet Fitting 46 Valve Assembly Power Spark Advance The distributor utilizes changes in air pressure within the carburetor to control spark timing to satisfy all engine speed and load conditions In order to obtain a vacuum to operate the spark advance as dictated by the engine speed and load conditions a port is located in the throttle bore just above the full closed position of the throttle valves HOLLEY 4160 FUEL SYSTEM 14 45 47 Gasket Power Valve 48 Primary Jets 49 Needle Idie Adjusting Mixture 50 Gasket Idle Mixture Needle 51 Screws Choke Valve 52 Choke Valve 53 Choke Shaft amp Lever Assembly 54 Discharge Nozzle Screw Pump 55 Gasket Nozzle Screw 56 Nozzle Pump Discharge 57 Needle Pump Discharge Jet 58 Cotter Pins Connecting Rods 59 Rod Secondary Connecting 60 Screw and Lockwasher Fast Idle Cam Lever 61 Lever Fast Idle Cam 62 Screws Primary Throttle Valve 63 Throttle Valves Primary 64 Screw Pump Cam 65 Cam 66 Screw and Lockwasher Secondary Stop Lever 67 Lever Sec
53. E CARE WHEN HANDLING AIR HORN SO AS NOT TO BEND OR DAMAGE WELL TUBES Fig 6 8 Disengage accelerator pump plunger from pump shaft by pushing up on bottom of plunger then tilting slightly toward center then slide off pump shaft Slide plunger stem out of air horn and remove compression spring Fig 7 9 Slide accelerator pump shaft out of air horn Fig 8 10 Remove fuel inlet fitting and gasket from air horn 11 With air horn inverted remove screw that at taches fuel baffle to air horn Fig 9 12 Slide nylon float fulcrum pin out of air horn then remove float Invert air horn and drop out fuel inlet needle Using a wide blade screw driver remove fuel inlet needle valve seat and gasket Fig 10 13 Remove air horn gasket Note This gasket is a self sealing type and will stick to air horn mounting surface Care should be used at removal so as not to CHOKE VACUUM DIAPHRAGM THROTTLE VALVES CRANKCASE VENT TUBE FITTING CARBURETOR AIR HORN VENT TUBE FITTING LIMITER CAP IDLE MIXTURE FUEL INLET FITTING SCREWS DISTRIBUTOR GROUND SWITCH CONNECTOR THROTTLE BODY ATTACHING SCREWS DISTRIBUTOR VACUUM ADVANCE TUBE FITTING PY835 Fig 1 Carburetor Assembly 1 11 ACCELERATOR PUMP ROCKER ARM CENTER SLOT OF ARM FLATS ON SHAFT CHOKE LEVER ACCELERATOR PUMP ROD THROTTLE LEVER LOCKWASHER gt PY836 Fig 2 Removing or Ins
54. EASSEMBLY DO NOT clean any rubber or plastic parts including diaphragms and electrical parts that may be attached to carburetor in cleaning solvent because of possible damage Check for cracks warpage stripped screw threads damaged or marred mating surfaces on all major castings The passages in the castings should be free of restrictions Install new castings as required Check float assembly for damage or any condition that would impair this item from further service The choke and throttle valves should be replaced if the edges have been nicked or if the protective plating has been re moved Be sure that the choke and throttle shafts are not bent or scored Replace any broken or distorted Springs Replace all threads and lockwashers that show signs of stripped threads or distortion Throttle Body If the throttle valves were removed because of dam CHECK NEEDLE PY849 Fig 15 Installing Accelerator Pump Discharge Check Needle 14 22 FUEL SYSTEM HOLLEY 2200 age install new valves as follows 1 Slide new valves into position in throttle shaft with the valve number on the bottom or mounting flange side and away from idle air mixture adjusting Screw ports 2 Install new valve screws but do not tighten 3 Hold valves in place with fingers Fingers press ing on high side of valves 4 Tap valve lightly with a screw driver to center in bores Now tighten valve attaching screws securely Operate the th
55. ERATOR PUMP PLUNGER STEM BOWL VENT VALVE ADJUSTING TANG ACCELERATOR PUMP ROCKER ARM PY834 Fig 1 Carburetor Assembly Holley 2210 Series systems The Idle System provides a rich mixture for smooth idle and low speed performance the Acceler ator Pump System provides additional fuel during acceleration the Main Metering System provides an economical mixture for normal cruising conditions and the Power Enrichment System provides a richer mixture when high power output is desired In addition to these four basic systems there is a fuel inlet system that constantly supplies the fuel to the basic metering systems and a choke system which temporarily enriches the mixture to aid in starting and running a cold engine Fuel Inlet System Fig 2 All fuel enters the fuel bowl through the fuel inlet fitting in the bowl cover The Viton tipped fuel inlet needle seats directly in the fuel inlet seat The fuel inlet needle is con trolled by a nitrophyl float a cellular buoyant mate rial which cannot collapse or leak and stainless steel float lever which is hinged by a Delrin float ful crum pin The fuel inlet system must constantly maintain the specified level of fuel as the basic fuel metering systems are calibrated to deliver the proper mixture only when the fuel is at this level When the fuel level in the bowl drops the float also drops permitting additional fuel to flow past the fuel inlet needle into the bowl A
56. Fig 2 Install attaching lock washer and nut Tighten securely 5 Install bowl vent valve lever on air horn by first inserting spring into position in arm with ends of spring pointing toward fuel inlet fitting Fig 5 Slide assembly over stub shaft on air horn Align spring and arm with stub shaft and end of spring over raised por tion of fuel inlet fitting Install clip to secure Vent valve should be in closed position 6 Install fast idle cam on air horn stub shaft with Steps toward fast idle adjusting screw Install clip to secure Fig 14 7 To install fast idle connector rod engage plain end in slot of fast idle cam from inside Engage other end of rod in choke lever With choke valve wide open AIR HORN UNDERSIDE SURFACE OF AIR HORN BOTTOM EDGE OF FLOAT FLOAT SHOULD BE PARALLED PY854 Fig 20 Checking Float Drop 14 24 FUEL SYSTEM HOLLEY 2200 slide lever over choke shafts aligning flats and point ing directly to fast idle cam stub shaft Fig 3 Install attaching lockwasher and nut Tighten securely Choke Vacuum Diaphragm Inspect the diaphragm vacuum fitting to be sure that the passage is not plugged with foreign material Leak check the diaphragm to determine if it has in ternal leaks To do this first depress the diaphragm stem then place a finger over the fitting to seal the opening Release the stem If the stem moves more than 1 16 inch in 10 ten seconds the
57. HRAGM RETURN E EU SPRING o p PUMP INLET CHECK BALL PASSAGE DIAPHRAGM NP603C Fig 8 Accelerating Pump System inlet check ball is moved off its seat and the dia phragm chamber is filled with fuel from the float bowl Secondary Throttle Operating System At lower speeds the secondary throttle valves re main nearly closed allowing the engine to maintain satisfactory fuel air velocities and distribution When engine speed increases to a point where additional breathing capacity is needed the vacuum controlled secondary throttle valves open automatically Vacuum taken from one of the primary barrels and one of the secondary barrels acts upon a diaphragm which controls the secondary throttle valves At high speeds when engine requirements approach the pacity of the two primary bores the increased pri mary venturi vacuum moves the diaphragm com pressing the diaphragm spring The diaphragm acting through the diaphragm link and lever will commence to open the secondary throttle valves Fig 9 The position of the secondary throttle valves de pends on the strength of the vacuum This in turn is determined by the air flow through the bores to the engine As the air flow increases a greater secondary throttle valve opening will result and the secondary barrels will supply a greater portion of the engine s requirements As top speed is reached the secondary throttle valves will approach wide open As
58. If an adjustment is necessary bend the shoe on the secondary throttle lever using Tool T 109 22 until correct clearance has been obtained BEND ROD AT THIS ANGLE PRIMARY THROTTLE pul VALVES be 4 SCALE SECONDARY SLOWLY OPEN THROTTLE THROTTLE VALVES VALVES SHOULD JUST START TO OPEN NOTCH OF yo Ed LOCKOUT DOG CHOKE VALVE WIDE OPEN TANG ON SECONDARY LEVER fe NR525A Fig 16 Checking Secondary Throttle Adjustment DRILL OR GAUGE Fig 17 Checking Clearance Between Closing Shoes Secondary Throttle Lock Ovt Adjustment Crack the throttle valves then manually open and close the choke valve The tang on the secondary throttle lever should freely engage in the notch of the lockout dog Fig 16 If an adjustment is necessary bend the tang on the secondary throttle lever until engagement has been made Use Tool T 109 22 for this operation After adjustments have been made reinstall carbu retor on engine using a new gasket It is suggested that the carburetor be filled with clean gasoline This will help prevent dirt that is trapped in the fuel system from being dislodged by the free flow of fuel as the carburetor is primed Bowl Vent Valve Adjustment C A S To check the bowl vent valve adjustment proceed as follows 1 With throttle valves tightly closed insert 1 8 inch drill between air horn and valve at smallest opening Fig 18 2 If an adjustment is necessary b
59. Install brake drum on axle flange 8 Slide stone shield up into position Install at taching screws and tighten securely 9 Install wheel and tire and tighten wheel nut to 65 foot pounds in sequence 10 Raise hoist and remove car stands 11 Install fender skirt if so equipped and lower vehicle to floor 12 Refill fuel tank and check for leaks 13 For testing fuel gauge tank unit refer to Electrical Group 8 Gauges THROTTLE LINKAGE ADJUSTMENT Automatic Transmission For adjustment of throttle linkage refer to Trans mission Section of this Manual Manual Transmission Fig 1 Chrysler with 383 or 440 In Eng 1 Apply a thin film of multi purpose grease on ball end and pocket 14 at rear end of throttle cable 2 Disconnect choke 8 at carburetor or block choke valve in full open position Open throttle 14 64 SPECIFICATIONS Fig 1 Throttle Linkage Adjustment 383 and 440 Engines slightly to release fast idle cam then return carbu retor to curb idle 3 Loosen cable clamp nut 4 adjust position of cable housing ferrule 5 in the clamp so that all slack is removed from cable with carburetor at curb idle To remove slack from cable move ferrule 5 in the clamp in direction away from carburetor lever 4 Back off ferrule 5 1 4 This provides 1 4 slack at idle Tighten cable clamp nut 4 to 45 inch pounds 5 Connect choke 8 rod or remove blocking fix
60. LEANER TO HOT IDLE TUBE FITTING COMPENSATOR VALVE COVER CHOKE VACUUM CLOSED CRANKCASE TUBE VENT TUBE HOKE VACUUM FITTING oe DIAPHRAGM BOWL VENT VALVE VENT TUBE CHOKE dir ex X MAIN BODY FUEL mee HE NEEDLE VALVE SEAT AND GASKET IDLE LIMITER IDLE MIXTURE ADJUSTING DISTRIBUTOR VACUUM ADVANCE TUBE FITTING A ACCELERATOR PUMP ROCKER ARM CHOKE VALVE BOWL VENT VALVE COVER ACCELERATOR PUMP ARM FAST IDLE CONNECTOR ROD eut DISTRIBUTOR a GROUND AIR HORN SWITCH TERMINAL Y FAST IDLE CAM SCREWS 2 THROTTLE LEVER THROTTLE BODY UNLOADER TANG ACCELERATOR PUMP ROD PY499 Fig 2 Carburetor Assembly BBD 1 1 2 inch E C S horn straight up and away from main body Discard gasket 2 screws recessed 9 Disengage accelerator pump plunger from ac celerator pump arm by pushing up on bottom of plunger and sliding plunger shaft off hook Slide plunger out of air horn and remove compression spring and seat Remove bowl vent valve cover If old plunger can be used again or if a new plung er is to be installed place plunger in a jar of clean AIR HORN HOT IDLE COMPENSATOR VALVE PY500 Fig 3 Removing or Installing Hot idle Compensator Valve gasoline or kerosene to prevent leather from drying out 10 Remove fuel inlet needle valve seat and gasket from main body 11 Lift out float fulcrum pin re
61. RATOR PUMP ROCKER ARM AIR VALVE STEP UP PISTON COVER PLATE 2 STEP UP PISTON COVER PLATE 2 CHOKE VACUUM THROTTLE DIAPHRAGM AIR LEVER BOWL VENT FUEL INLET HORN VALVE ARM TUBE FITTING N i Jy BOWL VENT VALVE ACCELE ADVANCE ROD CENTER HOLE TUBE FITTING CHOKE CONTROL S nog FAST mie HEVER CONNECTOR CHOKE X ROD DIAPHRAGM CLOSED CRANKCASE VENT 7 T CURB IDLE TUBE FITTING 48k get FAST IDLE LINK SPEED Yo eu ADJUSTING yi UNLOADER i SCREW DOMI i TANG J T IDLE MIXTURE ADJUSTING SECONDARY 72 ACCELERATOR SCREW LIMITER CAPS 26 THROTTLE LEVER THROTTLE PUMP ROD ACCELERATOR uM IDLE SPEED CONNECTOR LINK DIAPHRAGM PUMP ROD ADJUSTING SCREW 5 57 VACUUM SCREW LIMITER CAPS ACCELERATOR PUMP VACUUM CURB IDLE SPEED PLUNGER STEM DIAPHRAGM DISTRIBUTOR VACUUM ADJUSTING SCREW ADVANCE TUBE FITTING CARBURETOR ASSEMBLY AVS CASS ACCELERATOR PUMP CHOKE VALVE STEP UP PISTON KE PLUNGER STEM COVER PLATE 2 vayg ACCELERATOR PUMP ACCELERATOR PUMP BOWL VENT VALVE ACCELERATOR PLUNGER LINK AIR VALVE CHECKING OPENING AIR VALVE ROCKER ARM ARIN BOWL VENT VALVE PLUG THROTTLE TUBE FITTING FUEL INLET LEVER TUBE FITT FUEL INLET CURB IDLE CHOKE TUBE FITTING SPEED LEVER 1 ADJUSTING CHOKE CONTROL SCREW ACCELERATORS LEVER
62. RETOR PARTS The recommended solvent for gum deposits is denatured alcohol which is easily obtainable How ever there are other commercial solvents such as Metalclene which may be used with satisfactory re sults The choke diaphragm can be damaged by solvents Avoid placing the diaphragm assembly in ANY liquid Clean the external surfaces with a clean cloth or soft wire brush Shake dirt or other foreign material from the stem side of the diaphragm Depressing the dia phragm stem to the retracted position will provide an additional hole for the removal of dirt Compressed air can be used to remove loose dirt but should not be connected to the vacuum inlet fitting IMPORTANT If the commercial solvent or cleaner recommends the use of water as a rinse it should be HOT After rinsing all trace of water must be blown from the passages with air pressure It is further advisable to rinse all parts in clean gasoline or kerosene to be certain no trace of moisture remains Never clean jets with a wire drill or other mechanical means because the orifices may become enlarged making the fuel mixture too rich for proper per formance AUTOMATIC CHOKE Well Type new design well for the automatic choke has been incorporated in all engines except the 440 cu in tri carb installation and the 426 cu in Hemi This new design allows faster opening of the choke mechanism resulting in leaner fuel mixtures during the warm up period
63. ST IDLE SPEED f ADJUSTING SCREW Fig 20 Fast Idle Speed Adjustment On Vehicle NR529A FAST CURB IDLE SOLENOID 1 FAST CURB IDLE DISTRIBUTOR THROTTLE LEVER GROUND SWITCH SOLENOID FAST CURB IDLE LEAD PLUNGER ADJUSTING SCREW Fig 21 Idle Speed Solenoid Adjustment Idle Speed Solenoid Adjustment If so equipped To set idle speed solenoid for correct engine r p m proceed as follows 1 Warm up engine to normal operating tempera ture then attach a tachometer 2 With engine running turn idle speed solenoid adjusting screw in or out to obtain 900 r p m for manual transmission equipped vehicles and 800 r p m for automatic transmission equipped vehicles Fig 21 3 After specified r p m has been obtained and with engine still running to energize solenoid adjust curb idle speed screw until end of screw just touches stop on carburetor throttle body Now back off 1 full turn to obtain slow curb idle speed setting Ap proximately 650 to 700 r p m To set the idle speed on vehicles refer to the Fuel System General Information Paragraph HOLLEY 4160 FUEL SYSTEM 14 37 HOLLEY 4160 SERIES CARBURETOR INDEX Page Page Automatic Choke Well Type 1 Idle Speed Curb Idle 54 Carburetor Adjustments Secondary Throttle 54 Adjusting the Floats 49 Vacuum Kick On or Off Vehicle 53 Checkin
64. TLE VALVES WIDE OPEN POSITION 4 du NR453A Fig 19 Choke Unloader Adjustment Wide Open Kick HOLLEY 4160 FUEL SYSTEM 14 53 FAST IDLE CAM 2ND HIGHEST SPEED STEP Uu M 1 TURN SCREWDRIVER FOR ADJUSTMENT d 1 FAST IDLE SPEED ADJUSTING TANG lt FAST IDLE SPEED LEVER Fig 20 Fast Idle Speed Adjustment On Vehicle speed Bend the fast idle tang by use of a screwdriver placed in the tang slot to secure the specified speed CAUTION Bend only in a direction perpendicular to the contact surface of the cam Movement in any other direction changes the CAM POSITION ADJUSTMENT described earlier 4 Stopping the engine between adjustments is not necessary However reposition the fast idle tang on the cam after each speed adjustment to provide cor rect throttle closing torque Fast Idle Cam Position Adjustment The fast idle engine speed adjustment should be made on the vehicle as described in the Fast Idle Speed Adjustment on the vehicle paragraph How ever the Fast Idle Cam Position Adjustment can be made on the bench This adjustment is important to assure that the speeds of each step of the cam occur at the proper time during engine warm up 1 Qualify the choke control lever if necessary See Qualifying the Choke Control Lever Paragraph 2 With fast idle speed adjusting tang contacting second highest speed step on fast idle cam move choke valve toward the closed position
65. YSTEM AVS fitting Return fast idle linkage to its original condition if disturbed as suggested in step no 1 6 Make following check With no vacuum applied to diaphragm CHOKE VALVE SHOULD MOVE FREELY between open and closed positions If move ment is not free examine linkage for misalignment or interferences caused by bending operation Repeat adjustment if necessary to provide proper link opera tion Choke Unloader Adjustment The choke unloader is a mechanical device to par tially open the choke at wide open throttle It is used to eliminate choke enrichment during cranking of an engine Engines which have been flooded or stalled by excessive choke enrichment can be cleared by use of the unloader Adjust the system as follows 1 Hold throttle valves in wide open position In sert specified drill refer to Specifications between upper edge of choke valve and inner wall of air horn Fig 14 2 With a finger lightly pressing against choke lev er a slight drag should be felt as drill is being with drawn If an adjustment is necessary bend unloader tang on fast idle cam using Tool T 109 22 until cor rect opening has been obtained Fig 14 Accelerator Pump Adjustment Move the choke valve to wide open position to re lease the fast idle cam Back off the idle speed adjust ing screw curb idle until the throttle valves are seated in the bores Measure the distance from the top of the air horn to the top of the
66. a phragm stem from secondary stop lever Remove gas ket 12 Remove pump discharge nozzle retaining screw then lift out discharge nozzle Remove gasket from nozzle top and bottom 13 Remove screws that attach hot idle compensa tor valve cover to main body Lift off cover then re move valve and gasket Fig 5 If so equipped 14 Remove curb idle speed screw and spring Then remove insulating washer from between lead terminal and stop Remove distributor ground switch lead Us ing a thin blade screw driver remove insulator bush ing from boss on body Fig 5 15 Invert carburetor and drop out pump discharge jet needle from discharge passage 16 With carburetor inverted remove screws that DISTRIBUTOR GROUND SWITCH LEAD CURB IDLE SPEED J ADJUSTING SCREW GASKET VALVE 1 PE INSULATING BUSHING d INSULATING WASHER SWITCH TERMINAL SCREWS PY903 Fig 5 Removing or Installing Hot Idle Compensator Valve attach the throttle body to main body Fig 5 Remove throttle body and discard gasket Disassembling Fuel Bowls Primary and Secondary Primary 1 Remove primary bow vent valve assembly Fig 6 On E C S remove operating rod assembly 2 Remove float retainer clip then slide float and spring out of float chamber As float is being removed the fuel inlet needle may drop out of seat assembly Remove float baffle 3 Remove fuel inlet n
67. ain correct choke open ing Length changes should be made carefully by bending open or closing the bend provided in dia phragm link CAUTION DO NOT APPLY TWIST ING OR BENDING FORCE TO DIAPHRAGM 5 Reinstall vacuum hose on correct carburetor fit ting Return fast idle linkage to its original condition if disturbed as suggested in Step No 1 6 Make following check With no vacuum applied to diaphragm the CHOKE VALVE SHOULD MOVE FREELY between open and closed positions If move ment is not free examine linkage for misalignment or interferences caused by bending operation Repeat adjustment if necessary to provide proper link opera tion Choke Unloader Wide Open Kick The choke unloader is a mechanical device to par tially open the choke valve at wide open throttle It is used to eliminate choke enrichment during crank ing of an engine Engines which have been flooded or stalled by excessive choke enrichment can be cleared LIGHT CLOSING PRESSURE AGAINST CHOKE LEVER a CHOKE OPERATING LINK DIAPHRAGM STEM TO RETRACTED VACUUM f SOURCE fi 5 Uo APPLY 10 OR MORE INCHES OF VACUUM ON DIAPHRAGM PY503 Fig 13 Checking Choke Vacuum Kick Setting Wide Open Kick A by use of the unloader Adjust the choke unloader as follows 1 Hold throttle valves in wide open position In sert specified drill see Specifications between upper edge of choke valve and inner wall of air horn Fig
68. aps Install nuts but do not tighten FUEL SUPPLY TUBE LOCATING TANGS FILTER SUCTION TUBE FLOAT 1280 Fig 3 Fuel Gauge Tank Unit 5 Install new keystone clamps over vent hoses then slide vent tubes through frame side rail and in stall on vapor separator fittings Using keystone clamp pliers tighten hose clamps securely Fig 1 6 Guide button head of studs in slots in frame and down into position Tighten hold down strap at taching nuts securely 40 in lbs 7 Install filler tube mounting screw and tighten securely 8 Connect lead wire to tank gauge unit reconnect fuel line and ground strap Fig 4 9 Refill tank and check for leaks FUEL TANK Station Wagon Fig 2 Removal CAUTION Be sure the Ignition Switch is turned OFF before disconnecting or connecting the gauge wire 1 Remove filler cap and syphon fuel into safety can 2 Raise vehicle on hoist and remove fender skirt if so equipped 3 Remove left rear tire and wheel 4 Remove screws that attach stone shield to wheel house Slide shield down and away from vehicle 5 Disconnect fuel line ground strap and gauge wire Disconnect vent tubes 6 Place stands under frame at rear to support vehicle as hoist is lowered 7 Remove rear shock absorbers lower attaching CLIP FUEL GAUGE GROUNDING TUBE FUEL LINE WIRING FUEL GAUGE TANK UNIT TUBE FUEL GAUGE TANK UNIT Hit p CLIP
69. ats on pump shaft then disengage acceler ator pump rod from center slot in arm and from hole in throttle lever Fig 2 3 Remove nut and washer that attaches choke lever to choke shaft Disengage fast idle connector rod from lever and fast idle cam Fig 3 4 Remove choke vacuum diaphragm hose from throttle body tube fitting Remove screws that attach choke diaphragm and mounting bracket to air horn 5 Remove choke diaphragm and at the same time disengage choke operating link from slot in choke operating lever Fig 4 Place choke unit to one side to be cleaned as a special item A liquid cleaner may damage diaphragm material 6 Remove clip that retains bowl vent valve operating lever on stub shaft of air horn Slide lever FAST IDLE SPEED ADJUSTING SCREW CURB IDLE SPEED ADJUSTING SCREW BOWL VENT VALVE FAST IDLE CAM LEVER NH LIMITER CAP IDLE MIXTURE PUMP ROD A Re DISTRIBUTOR VACUUM CHOKE VACUUM DIAPHRAGM CRANKCASE VENT TUBE FITTING CHOKE VACUUM DIAPHRAGM HOSE CARBURETOR AIR CLEANER VENT TUBE FITTING CURB IDLE SPEED ADJUSTING SCREW FAST IDLE SPEED ADJUSTING SCREW THROTTLE LEVER j CHOKE OPERATING ADVANCE TUBE FITTING off shaft being careful not to lose lever spring Note position of spring Fig 5 7 Remove eight air horn ataching screws then lift air horn straight up and away from main body long screw in center USE EXTREM
70. baffle over the needle assists in separat ing the air bubbles from the fuel to provide a more solid fuel supply in the bowl The float chamber is vented internally into the air horn An external vent actuated by the pump lever is opened at curb idle or when the engine is not run ning to release fuel vapors from the bowl FUEL INLET FITTING FLOAT FLOAT ADJUSTING TAB PY863 Fig 2 Fuel Inlet System 14 16 FUEL SYSTEM HOLLEY 2200 Idle System Fig 3 Fuel used during curb idle and low speed oper ation flows through the main metering jet into the main well A horizontal connecting passage permits the fuel to flow from the main well into the idle well Fuel con tinues up the idle well and through an idle feed restriction into an idle channel where the fuel is mixed with air which enters through idle air bleeds located in the air horn At curb idle the fuel and air mixture flows down the idle channel and is further mixed or broken up by air entering the idle channel through the transfer slot which is above the throttle valve at curb idle During low speed operation the throttle valve moves exposing the transfer slot and fuel begins to flow through the transfer slot as well as the idle port As the throttle valves are opened further and engine speed increases the air flow through the car buretor also increases This increased air flow creates a vacuum or depression in the venturi and the main metering system begins to d
71. be under kickup in floor pan is open If SIDE EXTENSION SPRING NUT FLOOR PAN SCREW 4 SCREW SHIELD VAPOR TUBE VAPOR SEPARATOR TO FRONT OF VEHICLE CLAMP WHEELHOUSE SCREW 4 GASKET SIDE EXTENSION HOSE CLAMP PY878 Fig 1 Fuel Tank Assembly E C S Evaporation Control System Sedans 14 62 FUEL SYSTEM FUEL TANK KEE yg 5 hy Age EE FUEL SUPPLY TUBE STRAP VAPOR TUBE TO FRONT OF VEHICLE NUT FILLER NECK BRACKET STRAP WHEELHOUSE VENT TUBE BRACKET J BOLT Fig 2 Fuel Tank Asembly E C S Evaporation Control System Station Wagons this is not done a collapsed fuel tank will result The fuel tank on all models except Station Wagon has a 23 gallon 20 Imperial capacity The Sta tion Wagon capacity is 22 18 1 4 Imperial gallons The filler tube on the conventional models is ac cessible through the center of the deck opening lower panel while the Station Wagon fills at the left rear upper quarter panel between the quarter post and the fin The fuel tank is fitted with a gauge unit including the suction pipe Fig 3 The filter on the end of the suction pipe is replaceable unit and prevents the entry of water and dirt When installing a tank unit be sure the filter is pushed on the end of the tube until seated REMOVING THE FUEL TANK Except Station Wagon CAUTION Be sure the ignition switch is turned off before
72. ble to remove the throttle shaft or valves from the throttle body unless wear or damage necessitates the installation of new parts There is about 005 inch clearance between the throttle shaft and the throttle shaft bores in the throt tle body Any clearance over 010 inch a new throttle shaft and or throttle body should be installed INSPECTION AND REASSEMBLY Throttle Body 1 Inspect the throttle shaft and throttle body for excessive wear If either or both are worn to the point where the carburetor operation will be affected re place as required During manufacture the location of the idle trans fer port and the spark advance control ports to the throttle valve is carefully established for one particu lar assembly Fig 7 If a new shaft should be installed in an old worn throttle body it would be very unlikely that the origi nal relationship of the ports to the valves would be Obtained Changing the relationship of the valves to the ports would adversely affect normal car operation between the speeds of 15 and 30 miles per hour If it has been determined however that a new shaft or BBD FUEL SYSTEM VENTURI CLUSTER SCREWS 1 i 3 14 9 2 VENTURI CLUSTER GASKET ENT eo ic PUMP DISCHARGE A 2 HOLES B E377 GASKET t ACCELERATOR PUMP DISCHARGE CHECK BALL Say NR381 Fig 6 Removing or Installing Venturi Cluster valves is to be installed
73. ch re tards the distributor when the carburetor is at curb idle for better emission control Since the service procedures are identical on all BBD carburetors the illustrations showing the vari ous disassembly procedures will not always show any one specific carburetor BBD FUEL SYSTEM 14 7 The Ball and Ball carburetor is of the dual down draft type Each throat has its own throttle valve and main metering systems and are supplemented by the float accelerating idle and power systems On each BBD series carburetor the model number is stamped on metal tag attached to air horn Do not remove or destroy this tag as it is the only means provided for carburetor model identification Before attempting to repair or overhaul carburetor refer to model number and secure a repair kit for number indicated on tag SERVICE PROCEDURES DISASSEMBLING CARBURETOR Figs 1 or 2 1 insert three Tool T 109 287S and one Tool T 109 288S elevating legs through carburetor throttle body stud holes These tools are used to protect throttle valves from damage and to provide a suitable base for working 2 Remove hairpin clip and disengage fast idle connector rod from fast idle cam and cboke lever 3 Remove hairpin clip and disengage accelerator rod from throttle lever and pump rocker arm 4 Remove vacuum hose between carburetor throt ACCELERATOR PUMP ROCKER ARM tle body fitting and vacuum diaphragm 5 Remove clip from c
74. d to increase carburetor air flow to main tain satisfactory cold engine speed levels The prop er cam step is moved into position as the choke rod is moved from closed to open conditions Each step permits a slower idle rpm as engine temperature rises and choking is reduced gt VACUUM DIAPHRAGM A sy S i 2 CHOKE CONTROL LEVER ME VACUUM N BE TUBE THERMOSTATIC FW FAST IDLE COIL SPRING p 37 CAM LEVER ASSEMBLY WN NP606B Fig 11 Automatic Choke System FUEL SYSTEM HOLLEY 4160 14 44 24694N 81A popojdx3 A quiessy 10491nq405 1 1814 A 1 Lever Pump Operating 2 Locknut 3 Spring override 4 Screw Pump Adjusting 5 Screw Fuel Bowl Primary 6 Gasket Bow Screw 7 Fuel Bow Primary 8 Gasket Fuel Bowl 9 Metering Body Primary Side 10 Gasket Metering Body 11 Fuel Tube Float Bowl Connecting 12 50 Rings Fuel Tube 13 Screw Fuel Bowl Secondary 14 Gasket Bowl Screw 15 Fuel Bowl Secondary 16 Screw Metering Body Secondary 17 Metering Body Secondary 18 Gasket Metering Body Secondary 19 Plate Metering Body Secondary 20 Gasket Metering Body Plate 21 Balance Tube 22 Washers Balance Tube 23 O Rings Balance Tube 24 Choke Link 25 Seal Choke Rod 26 Throttle Body Screws 27 Main Body 28 Throttle Body 29 Gasket Main to Throttle Body 30 Screw Bowl Vent Valve Rod Clamp 31
75. disconnecting or connecting the gauge wire Removal 1 Drain tank into a safety can then disconnect fuel line and wire lead to gauge unit 2 Remove keystone clamps from vent hoses at vapor separator then slide vent tubes out of frame side rail Fig 1 3 Remove screw that attaches filler tube bracket to rear crossmember 4 Remove nuts that hold ends of fuel tank hold down straps to frame Lower front end of tank far enough to disengage filler tube from rear panel and slide out from under vehicle 5 Remove tank gauge unit using spanner wrench Tool C 3582 Fig 3 Check rubber grommet around filler tube If cracked or deteriorated install a new grommet at reassembly installation Before installing the tank gauge unit check the condition of the filter on the end of suction tube If the filter is plugged install a new filter 1 Position fuel tank gauge unit in tank using a new gasket Tighten securely using Tool C 3582 If tank insulator was torn or damaged during removal of tank be sure and install a new insulator at reassem bly Install vent hoses on tank if removed 2 Slide fuel tank under vehicle Raise tank far enough to engage filler spout with opening in rear panel and locator embossments on floor pan 3 Push tank toward rear to fully engage filler spout in opening 4 Hold fuel tank in this position and place hold down straps in position feeding attaching studs through holes in end of str
76. ds the leakage is excessive and the assembly must be replaced Install the diaphragm assembly on the car buretor as follows 1 Assemble to carburetor and tighten attaching screws securely 2 Install choke operating link in position between diaphragm plunger stem and choke lever Install 2 STEPS P COVER mee AO 22222 4 4 a 2 STAGE STEP UP PIECE ROD STEP UP PISTON SPRING PISTON ey SCREW JET NEW TYPE 9 8171 Fig 11 Step Up Piston Rod and Jet A clip to secure Secure choke lever end with spring E clip 3 Inspect rubber hose for cracks before placing it on correct carburetor fitting Fig 1 Do not connect the vacuum hose to the diaphragm fitting until after the vacuum kick adjustment has been made See Car buretor Adjustments CARBURETOR ADJUSTMENTS The following adjustments should be made with the carburetor on the bench for ease of working and should be made in the following order Fast Idle Speed Cam Position Adjustment The fast idle engine speed adjustment should be made on the vehicle as described in the Fast Idle Speed Adjustment On Vehicle Paragraph However the Fast Idle Cam Position Adjustment can be made on the bench This adjustment is important to assure that the speeds of each cam step occur at the proper time during engine warm up Adjust as follows 1 With fast idle speed adjusting screw contacting second highest speed step on fast idle
77. e hole in the release valve housing An immediate leak with light blowing or lack of release with hard blowing indicates a defective or incorrect unit 3 ECS lines plugged between fuel tank and vapor separator 4 Plugged ECS lines between the vapor separator and the crankcase air inlet filter 5 Plugged fuel tank expansion chamber inlet hole in main tank A removable plug is provided in the top surface of ECS fuel tanks for access to expansion chamber in event of plugging of its fill drain hole If purging of the fuel tank is required the expansion chamber must be purged separately through the top access plug hole SERVICE PROCEDURES The fuel tank on all models except Station Wagon Models is located at the rear of the body under the trunk compartment floor Fig 1 In Station Wagon models the fuel tank is mounted in the left rear quarter panel beyond the wheel house Fig 2 FRAME BRACKET n 7 5 aye BOLT FUEL TANK a 12 ASSEMBLY NUT M 2 STRAP 22222 CROSS MEMBER FUEL TANK ASSEMBLY BRACKET lt SCREW e y gt KS 5 7 CLAMP 2 CROSS MEMBER FILLER TUBE SIDE RAIL INSULATOR BOLTS VAPOR TUBES FLOOR PAN if the vehicle is to be stored for any appreciable length of time the gasoline should be drained from the entire system in order to prevent gum formation If the vehicle has been undercoated be sure the fuel tank vent tu
78. e the screws that attach the secondary throt tle valves to the throttle shaft and slide valve or valves out of bores SPARK ADVANCE PORT IDLE DISCHARGE PORTS PRIMARY Ej id THROTTLE e VALVES M SECONDARY THROTTLE VALVES IDLE TRANSFER PORTS NR517 Fig 6 Ports in Relation to Throttle Valves The primary valves and secondary valves are not interchangeable and should be kept separate in order that each may be returned to its respective bore Fig 7 INSPECTION AND REASSEMBLY 1 Slide primary throttle valve or valves into their respective bores install new screws but do not tighten Be sure idle speed adjusting screw is backed out Hold valves in place with fingers Fingers press ing on high side of valves 2 Tap valves lightly in this position tighten screws securely Stake screws by squeezing with pliers 3 Install idle mixture screws and springs in throt tle body The tapered portion must be straight and smooth If tapered portion is grooved or ridged a new idle mixture screw should be installed to insure having correct idle mixture control DO NOT USE A SCREW DRIVER Turn screws lightly against their seats with fingers Back off the number of turns counted at disassembly Install new plastic caps with tab against stops This screw has a left hand thread Turn counterclockwise Richer and clockwise Lean er 4 Be sure all the metering holes and
79. e throttle first then release choke 2 When using an auxiliary vacuum source dis connect vacuum hose from carburetor and connect it to hose from vacuum supply with a small length of tube to act as a fitting Removal of hose from dia phragm may require forces which damage the system Apply a vacuum of 10 or more inches 3 Insert specified drill refer to Specifications between choke valve and wall of air horn Fig 13 Apply sufficient closing pressure on lever to which choke rod attaches to provide a minimum choke valve opening without distortion of diaphragm link Note that on most units a cylinderical stem extends as an internal spring is compressed This spring must be fully compressed for proper measurement of vacuum kick adjustment 4 adjustment will be necessary if a slight drag is not obtained as drill is being removed Shorten or lengthen diaphragm link to obtain correct choke opening Length changes should be made by carefully opening or closing the bend provided in diaphragm link CAUTION DO NOT APPLY TWISTING OR BENDING FORCE TO DIAPHRAGM 5 Reinstall vacuum hose on correct carburetor DRILL OR GAUGE MINIMUM OF 10 INCHES OF VACUUM ON DIAPHRAGM SLOT REQUIRED CHOKE TO LEVER VACUUM SOURCE LIGHT CLOSING 4 7 23 VACUUM CHOKE TUBE HTTING fis ous LEVER DIAPHRAGM STEM RETRACTED PY728 Fig I3 Checking Choke Vacuum Kick Setting 14 34 FUEL S
80. ed with a hot idle compensator valve as is R 4369A above Fig 2 All of these carburetors are equipped with a dis tributor ground switch which retards the distributor when the carburetor is at curb idle for better emis sion control 440 Cubic Inch Engine The Holley four barrel carburetor model C A S Cleaner Air System R 4366A is used on the 440 cu in engine when the vehicle is equipped with an automatic transmission Fig 1 The Holley four barrel carburetor model E C S Evaporation Control System R 4360A is also used on the 440 cu in engine when the vehicle is equipped with an automatic transmission Fig 2 Both of these carburetors are equipped with a hot idle compensator valve This valve is a thermostatical ly operated air bleed to relieve an overrich condition at idle This condition is the result of excessive heat and resultant overrich mixtures The distributor ground switch retards the distributor when the car buretor is at curb idle for better emission control Since the service procedures are identical on all Holley four barrel carburetors the illustrations show ing the various disassembly procedures will not always show any one specific carburetor The Holley 4160 Series Carburetor Figs 1 2 and 3 can be considered as two dual downdraft carburetors mounted side by side each having its own fuel bowl and float system The two fuel bowls insure a constant supply of fuel for all the fuel metering sy
81. eedle valve seat Discard the gasket 4 Remove screws attaching accelerator pump cover Remove cover then carefully remove dia phragm and spring 5 Remove fuel inlet fitting and discard gasket 6 Remove screws attaching bowl vent valve cover to fuel bowl Lift off cover and remove vent valve spring and seal Fig 1 Remove seal from bottom of valve Secondary 1 Remove float retainer E clip then slide float and spring out of float chamber As float is being re moved the fuel inlet needle may drop out of seat as sembly Remove float baffle 2 Remove fuel inlet needle valve seat Discard gasket 11 should be noted that the Primary and Secondary fuel bowl baffles are of a different design and should be installed in the correct bowl at reassembly Disassembling Main Metering Body Primar 1 Using Tool C 3747 remove power valve assem bly from primary metering body Fig 7 2 Using Tool C 3748 remove main metering jets Fig 8 3 Remove idle adjusting needles and gaskets 4 Turn idle limiter caps to stops Remove caps by BOWL VENT BAFFLE PLATE VALVE _ FLOAT FLOAT PIVOT PIN FLOAT RETAINER ff EU CLIP FUEL INLET ACCELERATOR rae NEEDLE PUMP COVER FLOAT AND SEAT AND LEVER SPRING ASSEMBLY NP759 Fig 6 Primary Fuel Bowl Assembly HOLLEY 4160 FUEL SYSTEM ec Tren 2 Huren ca MS
82. eel tubing mounted at an angle inside the trunk of the vehicle quarter panel which internally holds four vent lines from the tank and a vent line which leads to the crankcase inlet air cleaner These lines are of different heights so the tank will always be vented regardless of vehicle attitude and fuel vapor will be transferred to the crankcase One vent line from the tank is short to provide a drain back to the tank for any liquid fuel which may get into the separator dur ing maneuvers or incline parking The vent to the crankcase is at the highest point in the separator and VAPOR LIQUID SEPARATOR VENT LIQUID RETURN LINE PRESSURE DPL J VACUUM RELIEF CAP PY940 Fig 1 Evaporation Control System has a small orifice to minimize liquid fuel transfer to the crankcase Fig 1 The ECS system also includes closed ventilation of fuel vapor from the carburetor bowl On eight cylin FUEL TANK FUEL SYSTEM 14 61 der engines this is accomplished via a hose connec tion from the carburetor bowl to the crankcase inlet air cleaner SERVICE DIAGNOSIS The ECS system should not require any mainte nance in normal service Any loss of fuel or vapor from the fuel filler cap would indicate one or more of the following 1 An unsatisfactory seal between cap and filler neck 2 A malfunction of ECS cap release valve A quick check of the ECS fuel cap may be made by placing against the mouth and blowing into th
83. el economy without sacrificing performance in the GASKET IN PLACE HORT FLOAT GAUGE 22 GAUGE OUTER END OF FLOAT NR519 Fig 9 Checking Float Height LEVEL FLOAT POSITION Fig 10 Checking Float Drop intermediate speed range To do this there is a step up piston new metering rods with three diameters and primary metering jets Fig 11 5 Slide step up piston spring into piston cylinders followed by step up pistons and step up rods Install cover plates and attaching screws while holding step up pistons down in position Tighten screws securely 6 Check fit of choke valve in air horn The valve should be evenly spaced on all sides Loosen screws and reposition if necessary 7 Engage throttle connector rod with hole in throttle lever Install other end in accelerator pump rocker arm center hole and install hairpin clip to secure 8 Engage upper end of fast idle connector rod in slot of choke operating lever Swing rod in an arc and engage with fast idle cam Secure with hairpin clip Installing Vacuum Diaphragm Inspect the diaphragm vacuum fitting to be sure that the passage is not plugged with foreign material Leak check the diaphragm to determine if it has in ternal leaks To do this first depress the diaphragm stem then place a finger over the vacuum fitting to seal the opening Release the diaphragm stem If the stem moves more than 1 16 inch in ten 10 secon
84. em consists of a power valve installed in the center of the carburetor body between the main jets and a vacuum piston installed in the bowl cover vacuum passage leads from the top of the piston down to the manifold flange When manifold vacuum is high the vacuum piston is raised to the top of its cylinder and the spring on the piston stem is compressed VACUUM PASSAGE POWER VALVE PISTON POWER VALVE CHANNEL RESTRICTION PYB66 POWER VALVE 27 POWER VALVE Fig 5 Power Enrichment System When manifold vacuum drops to a predetermined level the spring overcomes the vacuum and pushes the piston stem down The piston stem in turn pushes the power valve stem down opening the power valve and permitting fuel to flow through the power valve through power valve channel restrictions and into the main well on either side of the power valve Accelerating Pump System Fig 6 When the throttle valves are opened suddenly the air flow through the carburetor responds almost im mediately However there is a brief time interval or lag before the fuel can overcome its inertia and maintain the desired fuel air ratio The piston type accelerating pump system mechan ically supplies the fuel necessary to overcome this deficiency for a short period of time Fuel enters the pump cylinder from the fuel bowl through a slot in the pump well above the normal position of the pump piston When the engine is turned off fuel vapors in the pum
85. en the float height is correct Air Horn 1 Test freeness of choke mechanism in air horn The choke shaft must float free to operate correctly If choke shaft sticks in bearing areas or appears to be gummed from deposits in air horn a thorough cleaning will be required 2 Remove accelerator pump plunger from gaso line slide compression spring and spring seat over shaft Install assembly in air horn and engage with accelerator pump arm 3 Place a new gasket on main body and install air horn Install attaching screws and tighten securely When installing air horn be sure leather on plung er does not wrinkle or fold back 4 Engage accelerator pump rod with pump rocker arm and install loose end in outer hole of throttle lever Install hairpin clip to secure Fig 1 5 Engage fast idle connector rod loop at top in fast idle cam and in slotted choke lever Install retain ing clips to secure 6 Install hot idle compensator valve gasket in posi tion in recess in main body followed by valve Be sure valve is positioned with legs toward outside of main body Fig 3 Place cover over opening and install attaching screws Tighten securely If so equipped Choke Vacuum Diaphragm Inspect the diaphragm vacuum fitting to be sure that the passage is not plugged with foreign material Leak check the diaphragm to determine if it has in ternal leaks To do this first depress the diaphragm stem then place a finger over
86. end adjusting tang on pivot end of lever until correct opening has been obtained Bowl Vent Valve Adjustment E C S To check the bowl vent valve adjustment proceed as follows 1 Using Tool T109 43 remove bowl vent valve checking hole plug in air horn 2 With throttle valves at closed curb idle position insert a narrow ruler down through hole Allow ruler to rest lightly on top of valve The reading should be 3 4 inch from top of valve to top of air horn casting at opening Fig 18 3 If an adjustment is necessary bend bowl vent AVS FUEL SYSTEM 14 35 BOWL VENT gi VALVE CHECKING E Y Ball BOWL VENT VALVE OPERATING ON THROTTLE VALVES CLOSED h x TO CURB IDLE PO BEND LEVER P FOR ADJUSTMENT PY731 VENT VALVE iS DRILL GAUGE THROTTLE VALVES CLOSED NR528A i SEAT ON AIR HORN Fig 18 Bowl Vent Valve Adjustment C A S E C S valve operating lever until correct valve opening has been obtained 4 Install new plug and rap lightly to seat using a hammer Secondary Air Valve Adjustment 1 Loosen lock screw Fig 19 and allow air valve to position itself at wide open position 2 From wide open position spring barely moving valve turn slotted sleeve two full turns counter clock wise Fig 19 3 Hold in this position with finger then tighten lock screw securely Check valve for freedom of movement idie Speed
87. er other reliable makes of analyzers in good condition may be used Proceed as follows 1 Engine running at normal operating tempera ture and timing checked refer to Distributor Speci fications 2 Air Cleaner installed 3 Automatic transmissions in neutral position not in park position 4 On air conditioned cars turn air conditioning off 5 Connect ignition tachometer 6 Insert probe of exhaust gas analyzer in tail pipe as far as possible 2 ft minimum distance On dual exhaust cars use left side tail pipe side opposite heat valve It is very important that probe and con necting tubing be free of leaks to prevent erroneous reading If a garage exhaust system is used to con duct exhaust gases away a plenum chamber or other means must be used to reduce vacuum or exhaust system to 1 2 inch water or less 7 Connect exhaust gas analyzer warm up and calibrate according to manufacturer s instructions 8 Disconnect hose between distributor vacuum control valve and intake manifold 9 Set idle speed to specified value for specific engine transmission combination 10 IMPORTANT When adjusting mixture screws FUEL SYSTEM 143 to obtain air fuel ratio specified do not turn the mix ture screw more than 1 16 turn at a time The com bustion analyzer is so sensitive that the ratio must be changed in very small increments if accurate readings are to be obtained The meters read in air fuel ratio so that a h
88. ever clean jets with a wire drill or other mechanical means because the orifices may become enlarged making the fuel mixture too rich for proper perform ance DO NOT clean any rubber diaphragms or plastic parts in cleaning solvent because of possible damage INSPECTION AND REASSEMBLY Throttle Body If the throttle valves were removed because of damage install new valves as follows 1 Slide new primary throttle valves in position on throttle shaft with the valve number on the bottom ange side and toward idle transfer and spark ad vance control ports 2 Install new attaching screws but do not tighten 3 Hold valves in place with fingers Fingers press ing on high side of valves 4 Tap valves lightly with screwdriver in this posi tion to center in bores Tighten securely Operate the throttle shafts From closed to open position they must operate smoothly without drag or sticking Hold throttle body up to a strong light The light which is visible around the outer diameter of the valves and the bores should be uniform 5 Install secondary throttle valves in the same manner as described previously The numbers stamped on the valves must be toward idle transfer and spark advance ports in primary bores For adjust ment See Secondary Throttle Adjustment Assembling Main Metering Body Primary 1 Install idle mixture screws and springs in meter ing body The tapered portion must be straight and smooth If
89. f fuel Fig 4 14 38 FUEL SYSTEM HOLLEY 4160 CHOKE VALVE SECONDARY FUEL BOWL CHOKE LINK IDLE MIXTURE SCREW LEFT HAND THREAD SECONDARY VACUUM DIAPHRAGM BOWL VENT VALVE METERING BLOCK CAM POSITION PRIMARY FUEL BOWL ADJUSTING TANG 3 DISTRIBUTOR VACUUM CONNECTION icm DIAPHRAGM HOSE SECONDARY STOP LEVER zug CHOKE CONTROL LEVER CLOSED CRANKCASE CHOKE FAST IDLE CAM VENT TUBE FITTING VACUUM 3 DIAPHRAGM CHOKE UNLOADER LEVER CAS CARBURETOR P NR449B CHOKE VALVE GUARD CHOKE VALVE BOWL VENT VALVE SECONDARY VACUUM DIAPHRAGM FUEL TRANSFER TUBE IDLE MIXTURE FUEL BOWL ADJUSTING SCREW LIMITER CAP CARBURETOR TO AIR CLEANER VENT TUBE FITTING ACCELERATOR me ADJUSTING NUT HOT IDLE COMPENSATOR VALVE COVER ACCELERATOR PUMP LEVER THROTTLE BODY CURB IDLE SPEED SECONDARY THROTTLE SHAFT ADJUSTING SCREW SECONDARY THROTTLE THROTTLE LEVER CONNECTING LINK PY871 Fig 1 Carburetor Assembly C A S HOLLEY 4160 FUEL SYSTEM 14 39 BOWL VENT VALVE OPERATING ROD HOT IDLE COMPENSATOR VALVE COVER CHOKE VALVE FUEL CHOKE IDLE MIXTURE BOWL VENT TRANSFER TUBE VACUUM ADJUSTING VALVE CHOKE VALVE SECORDARY DIAPHRAGM PLUNGER VACUUM BOWL V DIAPHRAGM WL VENT j SECONDARY RINS i FUEL VACUUM SWITCH BOWL BOWL DIAPHRAGM g CONNECTOR VENT VALVE OPERATING ROD IDLE MIXTURE
90. ff the added supply of fuel which is no longer required Accelerating Pump System Upon acceleration the air flow through the car buretor responds almost immediately to the increased throttle opening Therefore during the brief interval before the fuel which is heavier than air can gain speed and main tain the desired balance of fuel and air the acceler ating pump supplies fuel until the other systems can once again provide the proper mixture Fig 8 The accelerating pump is located in the bottom of the primary fuel bowl The pump begins to function when the pump operating lever is actuated by throttle movement When the throttle is opened the pump linkage actuated by a cam on the primary throttle shaft forces the pump diaphragm up As the dia phragm moves up the pressure forces the pump inlet check ball on its seat preventing fuel from flowing back into the float chamber The fuel flows from the short passage in the fuel bowl into the long diagonal passage in the primary metering body The fuel passes into the main body and then in the pump discharge chamber The pressure of the fuel causes the dis charge needle valve to raise and fuel is discharged into the venturi As the throttle is moved toward the closed position the linkage returns to its original position and the diaphragm spring forces the diaphragm down As the diaphragm returns to its original position the pump DISCHARGE NOZZLE DISCHARGE NEEDLE DIAP
91. fications are ob tained Fuel level will vary 1 32 inch for every pound of fuel pump pressure under or over specifications FUEL PUMP INDEX Page Page Assembling Fuel Pump RD 267A 57 Service Diagnosis 55 Disassembling Fuel Pump RD 267A 57 Specifications 67 General Information 55 Testing Fuel Pump on car 56 GENERAL INFORMATION Fuel pump Model MS 4589SA and 5 48455 or Airtex RD 267A Optional Figs 1 or 2 is used on all Chrysler and Imperial engines The MS 4589SA and MS 4845S fuel pump are of the pressed steel type and cannot be disassembled for service If a pump mal function occurs remove the old pump and install a new one Airtex Model RD 267A Optional is service able The fuel pumps are driven by an eccentric cam that is cast on the camshaft in the 383 and 440 cubic inch engines As the camshaft rotates the eccentric cam presses down on the pump rocker arm On the 383 and 440 cubic inch engine a push rod operates between the camshaft and the fuel pump rocker arm This ac tion lifts the pull rod and diaphragm upwards against the fuel pump main spring thus creating a vacuum in the valve housing and opens the inlet valve and fuel is drawn into the valve housing chamber On the return stroke the main spring forces the diaphragm to the down position which closes the inlet
92. for reduced emissions and fuel consumption Fig 1 To function properly it is important that all parts be clean and move freely Other than an occasional cleaning the automatic choke control requires no servicing However it is very important that the choke control unit works freely at the thermostatic coil spring housing and at the choke shaft Move the choke rod up and down to check for free movement in the coil housing If unit binds a new unit should be in stalled The well type choke is serviced as an assembly Do not attempt to repair or change the setting unless authorized by service literature Changes of the choke setting materially affect summer temperature cold starting and seldom are a satisfactory correction of drive ability problems which are generally associated with carburetors or vacuum diaphragms Two types of wells are in general usage One is cast as an integral part of the manifold The second is a CHOKE CONTROL COVER UNIT THERMOSTATIC COIL SPRING STAINLESS STEEL CUP PY138 Fig Control Open Well 8 cylinder Engine 14 2 FUEL SYSTEM stainless steel cup fastened over a port in the mani fold Fig 1 The stainless steel well cups are held in place by choke retainer bolts A steel asbestos gasket seals the exhaust gas within the manifold Loosening or remov ing the choke retainer bolts will allow exhaust gases to escape into the engine compartment DO NOT RUN THE ENGINE WITHOUT
93. g until it eventually permits the choke to open fully Distributor Vacuum Advance As engine speed increases the spark timing must be advanced so that the burning in the cylinder may be completed at the proper time to achieve maximum pressure and efficiency A vacuum spark port located in the throttle bore just above the closed throttle valve is connected to the distributor vacuum chamber by a series of pas sages to a fitting in the carburetor body and a flexible hose As the throttle is opened this port is exposed to manifold vacuum which varies with changes in engine Speed and load This changing vacuum is applied to the distributor vacuum diaphragm The diaphragm in turn rotates the distributor breaker plate through a connecting rod changing the spark timing to meet engine demands At curb idle the curb idle screw contacts the dis tributor retarding solenoid This in turn retards the distributor to maximum retard for improved emission control at idle PY868 Fig 7 Automatic Choke System 14 18 FUEL SYSTEM HOLLEY 2200 SERVICE PROCEDURES DISASSEMBLING CARBURETOR 1 Insert three Tool T 109 287S and one Tool T109 2885 elevating legs through carburetor throttle body mounting stud holes These tools are used to protect throttle valves from damage and to provide a suitable base for working Fig 1 2 Remove nut and washer attaching accelerator pump rocker arm to accelerator pump shaft Remove arm from fl
94. g Bowl Vent Valve Clearance 51 Disassembling the Carburetor 45 Checking Pump Lever Clearance 52 Cleaning Carburetor Parts 48 Checking Wet Fuel Level 54 General Information 37 Choke Unloader Wide Open Kick 53 Inspection and Reassembly 48 Fast Idle Cam Position 53 Servicing 45 Fast Idle Speed On or Off Vehicle 53 Specifications 64 Idle Mixture 53 GENERAL INFORMATION 383 Cubic Inch Engine The Holley four barrel carburetor models C A S Cleaner Air System R 4367A R 4368A and R 4369A are used on the 383 cu in engines when the vehicles are equipped with manual or automatic transmissions respectively Model R 4369A is used with vehicles equipped with air conditioning only and has a hot idle compensator valve This valve is a thermostatically operated air bleed to relieve an overrich condition at idle This condition is the result of excessive heat and resultant overrich mixtures Fig 1 The Holley four barrel carburetor models E C S Evaporation Control System R 4217A and R 4218A are also used on the 383 cu in engines when the ve hicles are equipped with a manual or automatic transmission respectively These two carburetors are also equipp
95. hanical device to tially open the choke valve at wide open throttle It is used to eliminate choke enrichment during cranking of an engine Engines which have flooded or stalled by excessive choke enrichment can be cleared by use of the unloader Adjust the choke unloader as follows 1 Hold throttle valves in wide open position In sert specified drill see Specifications between upper edge of choke valve and inner wall of air horn Fig 23 2 With a finger lightly pressing against shaft DRILL OR GAUGE LIGHT CLOSING PRESSURE ON CHOKE LEVER BEND TANG ON THROTTLE LEVER TO ADJUST PY857 Fig 23 Choke Unloader Adjustment Wide Open Kick HOLLEY 2200 FUEL SYSTEM 14 25 gt ACCELERATOR PUMP 7 PLUNGER STEM ROD IN CENTER SLOT OF ARM THROTTLE AT FULLY CLOSED POSITION PY858 ACCELERATOR PUMP ROD FOR ADJUSTMENT Fig 24 Accelerator Pump Adjustment lever a slight drag should be felt as drill is being withdrawn If an adjustment is necessary bend un loader tang on throttle lever until correct opening has been obtained Fig 23 Use Tool T109 213 Accelerator Pump 1 Back off curb idle speed adjusting screw Open choke valve so that fast idle cam allows throttle valves to be completely seated in bores Be sure that pump connector rod is installed in center slot of accelerator pump rocker arm 2 Close throttle valves tightly Measure the dis tance betwee
96. he throttle body cast integral with the main body This allows an overall height reduction in the carburetor The section containing the accelerator pump is termed the primary side of the carburetor The rear section is the secondary The five conven tional systems used in previous four barrel carburet ors are also used in this unit The five conventional systems are two float systems two low speed systems primary side only two high speed systems one accelerator pump system and one automatic choke control system SERVICE PROCEDURES DISASSEMBLING CARBURETOR Fig 1 1 Place carburetor assembly on repair stand Tool C 3400 or T 109 287S elevating legs These tools are used to protect throttle valves from damage and to provide a suitable base for working 2 Remove hairpin clip that attaches fast idle con nector rod to fast idle cam Disengage rod from cam then swing rod at an arc until it can be disengaged from choke operating lever 3 Remove hairpin clip that holds throttle con nector rod in center hole of accelerator pump arm Disengage rod from arm and throttle lever then re move from carburetor 4 Remove screws attaching step up piston and rod cover plates Hold cover down with a finger to prevent piston and rods from flying out Lift off plates and slide step up pistons and rods out of air horn Fig 2 Remove step up piston springs 5 Remove vacuum hose between carburetor throt tle body and vacuum diaphragm
97. hen the fuel is at this level A float spring is incorporated under the float to keep the float in a stable position The float chamber is vented internally by the vent tube at all times At curb idle or when the engine is stopped the chamber is also vented by the external vent on top of the primary fuel bowl This external vent provides a release of excess fuel vapors from the bowl Idle System Fig 5 At idle and low speeds the air flow through the carburetor is not sufficiently strong enough to draw fuel through the primary barrel venturi for the main metering system Intake manifold vacuum is high be cause of the greater restriction to the air flow by the nearly closed throttle valves This high manifold vac uum is used to provide the pressure differential which operates the idle system The carburetor utilizes two idle systems one for each primary barrel Since the two passages function identically only one side will be considered in this explanation Fig 5 At idle the near atmospheric pressure in the float chamber causes the fuel to flow through the idle sys tem to the greatly reduced pressure area below throttle plate Fuel flows from the float chamber through a restriction into the curb idle well The fuel flows up this vertical idle well through the idle feed restriction and then it is mixed with air coming in from the idle air bleed This fuel air mix FUEL SYSTEM HOLLEY 4160
98. her stream is restricted or diverted remove cluster and reclean After test pour fue from the bowl and remove pump plunger 6 Install main metering jets Tighten securely Fig 5 PUMP PLUNGER anco wv 5 x EMITTED PAST PUM INTAKE CHECK BALL FUEL TO BE EMITTED PAST DISCHARGE CHECK BALL NR383 Fig 8 Testing Accelerator Pump Intake and Discharge Check Bails A 7 Before installing step up piston be sure step up rods are able to move freely each side of the vertical position Fig 9 The step up rods must be straight smooth and free to move forward and backward from vertical 8 Slide step piston gasket down into position in piston well then install the step up piston spring step up piston and rods Carefully guide step up rods into main metering jets Fig 4 Install retaining Screw and tighten securely Check piston for free operation in well step up piston stuck in the Up position will cause a rich mixture at part throttle whereas a piston stuck in the Down position will cause a lean mixture at wide open throttle and poor acceleration Measuring Float Setting The carburetors are equipped with a rubber tipped fuel inlet needle The rubber tip is flexible enough to make a good seal on the needle seat and to give increased resistance to flooding Care should be taken to perform this operation accurately in order to se cure the best performance and fuel economy
99. hoke operating link and dis engage link from diaphragm plunger and choke lever Figs 1 or 2 6 Remove vacuum diaphragm and bracket assem bly and place to one side to be cleaned as a special item A liquid cleaner may damage the diaphragm material 7 Remove screws that attach hot idle compensator valve cover to main body Remove cover and lift out hot idle compensator valve and gasket Fig 3 8 Remove air horn retaining screws and lift air ACCELERATOR DISTRIBUTOR GROUND BOWL VENT PUMP SWITCH TERMINAL VALVE PLUNGER CHOKE VALVE FUEL INLET i ak T NEEDLE VALVE SEAT MAIN FAST IDLE AND GASKET BODY CAM THROTTLE BODY THROTTLE LEVER IDLE LIMITER CAP 2 IDLE MIXTURE ADJUSTING SCREWS 2 UNLOADER TANG ACCELERATOR PUMP FAST IDLE CONNECTOR ROD CURB IDLE SPEED ADJUSTING SCREW CHOKE VACUUM DIAPHRAGM CHOKE VACUUM HOSE CHOKE LEVER CHOKE OPERATING SPIKE EYE LINK DIAPHRAGM STEM IDLE LIMITER CAP 2 IDLE MIXTURE ADJUSTING SCREWS 2 CLOSED CRANKCASE VENT TUBE FITTING DISTRIBUTOR VACUUM ADVANCE TUBE FITTING PY498 Fig 1 Carburetor Assembly BBD 1 1 2 inch C A S 148 FUEL SYSTEM BBD BOWL VENT VALVE COVER CHOKE OPERATING LINK BOWL VENT VALVE VENT TUBE FITTING CHOKE VALVE FAST IDLE SPEED ADJUSTING SCREW THROTTLE LEVER FAST IDLE CONNECTOR ROD CURB IDLE SPEED ADJUSTING SCREW AIR C
100. igher reading indicates a leaner mixture and vice versa a Adjust each screw 1 16 turn richer counter clockwise and wait 10 seconds before reading meter b If necessary repeat step until meter indi cates a definite increase in richness lower reading This step is very important since meter reverses its readings and indicates a richer mixture as carburetor is leaned out if carburetor is set too Jean c When it has been established that meter is indi cating a lower reading richer mixture when idle mixture screws are turned in richer direction pro ceed to adjust carburetor to give 14 2 air fuel ratio turning screws counterclockwise richer to lower meter reading and clockwise leaner to increase meter reading d If idle speed changes as mixture screws are turned adjust speed to specified value and readjust mixture as required so that 14 2 air fuel ratio is ob tained at specified idle speed ROUGH IDLE AND LOW SPEED SURGE Rouge idle and low speed surge on vehicles using 1 1 2 BBD AVS and Holley 4160 carburetors may be the result of improper idle setting balance between the right and left carburetor bores To correct this condition the following steps should be followed 1 Remove the plastic caps from the two idle screws in base of carburetor 1 1 2 BBD and AVS or cup or in the sides if the primary metering block Holley Figs 1 BBD AVS and Holley 2 With exhaust thoroughly warmed up in
101. ing a new gasket Tighten securely using Too C 3582 2 Work fuel tank up into position in quarter panel Move rearward until filler tube is centered in opening of quarter panel Place straps in position and install nuts Tighten to 40 inch pounds Bottom strap should be tightened first 8 Install fuel line and connect ground strap Fig 4 and fuel gauge wire 4 Raise hoist far enough to engage spring hanger with frame 5 Position left rear spring hanger at frame and install attaching bolts Tighten to 30 foot pounds 6 Slide shock absorbers over pivots and secure with nuts Tighten to 50 foot pounds 7 Install brake drum on axle flange 8 Slide stone shield up into position Install at taching screws and tighten securely 9 Install wheel and tire and tighten wheel nut to 65 foot pounds in sequence 10 Raise hoist and remove car stands 11 Install fender skirt if so equipped and lower vehicle to floor 12 Refill fuel tank and check for leaks 13 For testing fuel gauge tank unit refer to Electrical Group 8 Gauges 14 60 FUEL SYSTEM FUEL TANK FUEL TANKS E C S EVAPORATION CONTROL SYSTEM GENERAL INFORMATION Certain Chrysler Corporation Vehicles are equipped with an Evaporation Control System ECS to reduce the loss of fuel from the fuel system to the atmo sphere by evaporation This is a closed system which controls fuel expansion and feeds fuel evaporation emissions from the ca
102. ion causes this fuel flow from both the main metering and idle systems The thermostat spring of a cold engine pushes the choke valve toward the closed position When the engine is started manifold vacuum acts on both the choke valve and a vacuum diaphragm attached to the carburetor body This vacuum acts to oppose the ther mostat spring and partially opens the choke valve to prevent stalls from richness The choke shaft does not pass through the center of a choke valve Instead it is offset to expose a large area at one side to mani fold vacuum During idle or low temperature crank ing manifold vacuum is not sufficiently strong to open the choke valve But air impact against the valve causes partial opening These two factors vacuum and air impact allow ample air to run the engine Con tinued running of the engine develops heat and causes the thermostat assembly to move to the open choke position During the warm up period air flow past the par tially open offset choke valve acts to open the valve Just as in the start cycle vacuum and air impact com bine to control the choke valve The engine required less choking at high speeds The offset choke valve vacuum diaphragm and thermostat spring are engi neered to provide satisfactory choking for most condi tions of engine speed output and temperature Fast Idle The choke control lever at the carburetor actuates a fast idle cam during choking A cam has a series of steps designe
103. ir enters through the high speed air bleed in the main body and then into the main metering body by inter connecting passages This mixture of fuel and air being lighter than raw fuel responds faster to any change in venturi vacuum and vaporizes more readily HIGH SPEED AIR BLEED DISCHARGE NOZZLE IDLE TUBE MAIN JET NR557A Fig 6 Main Metering System HOLLEY 4160 FUEL SYSTEM 14 41 when discharged into the air stream of the venturi The mixture of fuel and moves up the main well and passes into the short horizontal passage leading to the main body then through the horizontal chan nel of the discharge nozzle This fuel is discharged into the booster venturi and then in the air stream of the carburetor venturi The throttle valve controls the amount of fuel air mixture admitted to the intake manifold regulating the speed and power output of the engine in accord ance with accelerator pedal movement Power Enrichment System During high power operation the carburetor must provide a mixture richer than is needed when the engine is running at cruising speed under no great power requirements The added fuel for power opera tion is supplied by the power enrichment system Fig 7 This system is controlled by manifold vacuum which gives an accurate indication of the power de mands placed upon the engine Manifold vacuum is strongest at idle and decreases as the load on the engine increases the load on the engine
104. is in creased the throttle valve must be opened wider to maintain a given speed Manifold vacuum is thus re duced because the opened throttle valve offers less restriction to air entering the intake manifold vacuum passage in the throttle body transmits manifold vacuum to the power valve chamber in the main body The power valve which is located in the main metering body is effected by this manifold vacuum The manifold vacuum acting on the dia phragm at idle or normal load conditions is strong enough to hold the diaphragm closed and overcomes the tension of the power valve spring When high power demands place a greater load on the engine and manifold vacuum drops below a predetermined point the power valve spring overcomes the reduced vacuum opening the power valve Fuel flows from the float chamber through the valve and out the small DISCHARGE NOZZLE HIGH SPEED 9 AIR BLEED BOOSTER VENTURI POWER VALVE RESTRICTION MAIN JET NP602C Fig 7 Power Enrichment System 14 42 FUEL SYSTEM HOLLEY 4160 holes in the side of the valve through the diagonal restrictions in the main metering body and then into the main well In the main well the fuel joins the fuel flow in the main metering system enriching the mix ture As engine power demands are reduced manifold vacuum increases The increased vacuum acts on the diaphragm overcoming the tension of the power valve spring This closes the power valve and shuts o
105. ischarge fuel Main Metering System Fig 4 As the engine approaches cruising speed the in creased air flow through the venturi creates vacuum low pressure area in the venturi of the carburetor Near atmospheric pressure present in the bowl in the area above the fuel causes the fuel to flow to the lower pressure area created by the venturi and mag nified by the booster venturi Fuel flows through the main jet into the main well air enters through the main well air bleeds and into the main well through holes in the main well tube The mixture of fuel and air being lighter than raw fuel responds faster to changes in venturi vacuum and is also more readily vaporized when discharged into the venturi IDLE FEED RESTRICTION IDLE AIR BLEED TRANSFER SLOT IDLE MIXTURE ADJUSTING NEEDLE IDLE PORT PY864 Fig 3 Idle System A MAIN WELL TUBE HIGH SPEED MAIN NOZZLE i METERING JET BOOSTER MAIN WELL VENTURI Fig 4 Main Metering System The main discharge nozzle passage is a part of the booster venturi which is an integral part of the main body casting Distribution tabs in the main venturi provide further vaporization of the fuel and air mix ture The main metering system is calibrated to deliver a lean mixture for best overall economy When addi tional power is required a vacuum operated power system enriches the fuel air mixture Power Enrichment System Fig 5 Tbe power enrichment syst
106. k float setting using Tool T 109 280 or a scale There should be 5 16 inch from surface of bowl gasket removed to crown of floats at center If an adjustment is necessary hold the floats on tbe bottom of the bowl then bend the float lip toward or away from the needle Recheck the 5 16 inch setting again then repeat the lip bending operation as re quired When bending the float lip do not allow the lip to push against the needle as the rubber tip can be compressed sufficiently to cause a false setting which will affect correct level of fuel in the bowl After being compressed the rubber tip is very slow to re cover its original shape t is very important that the float lip be perpendicular to the needle or slanted not more than 10 degrees away from the needle when the float is set correctly 5 After float has been correctly set reassemble the air horn Fast Idle Speed Adjustment On Vehicle Fast idle engine speed is used to overcome cold engine friction stalls after cold starts and stalls be cause of carburetor icing Set this adjustment after the vehicle odometer indicates over 500 miles to in sure a normal engine friction level Prepare engine by driving at least 5 miles Connect a tachometer and Fe i Dn CHOKE VALVE FAST IDLE SPEED ADJUSTING SCREW ON SECOND HIGHEST STEP OF CAM PY505 Fig 17 Fast Idle Speed Adjustment On Vehicle set the curb idle speed
107. l correct valve opening has been obtained Vacuum Kick Adjustment This test can be made On or Off vehicle The choke diaphragm adjustment controls the fuel delivery while the engine is running It positions the choke valve within the air horn by action of the link age between the choke shaft and the diaphragm The diaphragm must be energized to measure the vacuum bu MINIMUM OF LIGHT CLOSING PRESSURE ON CHOKE LEVER DRILL OR GAUGE FAST IDLE SPEED ADJUSTING SCREW ON SECOND HIGHEST STEP OF CAM ADJUST SCREW TO OBTAIN FAST IDLE SPEED 534 BEND 82 3 AT ANGLE FOR ADJUSTMENT E IDLE CAM SCREW 55 Fig 21 Fast Idle Speed and Cam Position Adjustment kick adjustment Use either a distributor test machine with a vacuum source or vacuum supplied by another vehicle 1 If adjustment is to be made with engine running disconnect fast idle linkage to allow choke to close to the kick position with engine at curb idle If an auxil 1 vacuum source is to be used open throttle valves engine not running and move choke to closed posi tion Release throttle first then release choke 2 When using an auxiliary vacuum source dis connect vacuum hose from carburetor and connect it to hose from vacuum supply with a small length of tube to act as a fitting Removal of hose from dia phragm may require forces which can damage the sys tem Apply a vacuum of 10 or more inches of merc
108. ly Then test fuel pump pressure Refer to Specifications for correct fuel pump pressure h Adjust valves i Check ignition system D Reset timing b d a Disassemble carburetor Replace ac celerator pump assembly if leather is hard cracked or worn Test follow up spring for compression Disassemble carburetor Use com pressed air to clean discharge nozzle and channels after soaking main body in a suitable solvent Test accelerator pump capacity Disassemble carburetor Check ac celerator pump inlet check ball for poor seat or release If part is faulty replace d Test fuel or float level in carburetor Adjust as necessary to obtain correct float level e Disassemble carburetor Replace worn accelerator pump and throttle linkage and measure for correct posi tion f Free up manifold heat control valve using recommended solvent g Test power piston operation h Reset timing i Reset pump a Disassemble carburetor Replace cracked body Make sure main to throttle body screws are tight b Condition POOR PERFORMANCE MIXTURE TOO RICH POOR COLD ENGINE STARTING INCORRECT PROCEDURE CHOKE VALVE FAILS TO CLOSE LOW ENGINE OUTPUT 10 F or lower Possible Cause b Faulty body gaskets c High float level d Worn needle valve and seat e Excessive fuel pump pressure a Restricted air cleaner b Leaking
109. marking one on pump side for identifica tion Using a wide blade screw driver remove needie vaive seats Be sure each needle valve is returned to its original seat at reassembly 3 Remove shoulder screw and spring holding ac celerator pump rocker arm and bow vent arm to air horn 5 Remove arms and disengage pump link from pump stem Slide accelerator pump plunger and spring out of air horn Remove gasket 4 Place accelerator pump plunger in a jar of clean gasoline or kerosene to prevent leather from drying out 5 Remove fuel inlet fitting and filter screen from air horn 6 Test freeness of choke mechanism in air horn The choke shaft must float free to operate correctly If choke shaft sticks in bearing area or appears to be gummed from deposits in air horn a thorough clean ing will be required Main Body Disassembly 1 Remove screws that attach accelerator pump jet housing to main body Lift out jet housing and gasket Fig 3 Discard gasket Now invert main body and drop out discharge check needle from discharge pas sage 2 Using Tool T 109 58 remove main metering jets primary side Fig 4 The primary and secondary main metering jets are not interchangeable It is very important that these jets be installed in their respective locations in the main body at reassembly 3 Again using Tool T 109 58 remove main meter ing jets secondary side Fig 4 Remove intake check 4 Remove screws that
110. n and engage pump link Install bowl vent arm in position over pump arm Slide spring over pivot screw and install through arms and boss Be sure shoulder of screw enters arms Tighten securely En gage ends of spring with tang on vent arm and pin on air horn Check for proper operation AVS FUEL SYSTEM 14 31 The carburetors are equipped with synthetic rub ber tipped fuel inlet needles The needle tip is a rub ber material which is not affected by gasoline and is stable over a wide range of temperatures The tip is flexible enough to make a good seal on the needle seat and to give increased resistance to flooding The use of new inlet needles require that care be used when making float adjustments Avoid applying any pressure on the floats which might compress the tip of the fuel inlet needles The tip can be com pressed sufficiently to cause a false setting which will affect correct level of fuel in the bowl 4 Place a new air horn to main body gasket in position on air horn then install float needle valve seats Be sure each needle seat and needle is rein stalled in its original position 5 Slide right and left floats into position in air horn then install float fulcrum pins Be sure marked float is installed on pump side of the air horn See disassembly procedures 6 After floats have been installed check float alignment level and drop settings as follows Float Alignment Setting 1 Sight down side of each floa
111. n top of air horn and end of plunger shaft Fig 24 This measurement should be 9 16 inch 3 To adjust pump travel bend pump operating rod using Tool T109 213 at loop of rod until correct setting has been obtained Bowl Vent 1 With curb idle speed adjusting screw at curb THROTTLE AT CURB IDLE PY859 Fig 25 Bowl Vent Adjustment 14 26 FUEL SYSTEM AVS idle there should be 5 64 inch clearance between bowl vent valve and seat on air horn when throttle valves are closed Fig 25 2 If an adjustment is necessary bend tang on ac celerator pump rocker arm using Tool T109 41 until correct vent valve opening has been obtained Idle Speed Adjustment Curb Idle Refer to General Information at Front of Section Fast Idle Speed Adjustment On Vehicle Fast idle engine speed is used to overcome cold engine friction stalls after cold starts and stalls be cause of carburetor icing Set this adjustment after the vehicle odometer indicates over 500 miles to in sure a normal engine friction level Prepare engine by driving at least five miles Connect a tachometer and set the curb idle speed and mixture then proceed as follows 1 With engine off and transmission in PARK or NEUTRAL position open throttle slightly 2 Close choke valve until fast idle screw can be positioned on second highest step of fast idle cam Fig 26 3 Start engine and determine stabilized speed Turn fast idle speed screw in or out
112. ocker arm follower spring 3 Remove screws holding rocker arm housing to valve body Separate body and housing 4 Press in on diaphragm and disengage rocker arm from diaphragm pull rod Remove rocker arm and spacer washers 5 Slide diaphragm and spring out of rocker arm housing 6 Remove sleeve from two piece rocker arm then separate rocker arm pull lever from eccentric arm Cleaning Fuel Pump Parts Clean all fuel pump parts except diaphragm in a suitable solvent then blow dry with compressed air Check the condition of the valve seats and parts for gum deposits If gum deposits are found remove with denatured alcohol If the valves are badly worn or damaged install a complete new valve body assem bly The valves are not serviced individually Exam ine the diaphragm for cracks torn screw holes or ruptures Check the rubber oil seal diaphragm pull FUEL TANK FUEL SYSTEM 14 57 rod in housing for deterioration If unfit for further service install a new rocker arm housing Check the rocker arm for scoring or galling on the camshaft push rod bearing surface ASSEMBLING FUEL PUMP 1 Assemble rocker arm by sliding the pull arm into eccentric cam and install sleeve Be sure the hook on the arm is facing up 2 Grease spacer washers and slide over each side of sleeve shoulder 3 Install diaphragm and spring rocker arm hous ing 4 Slide rocker arm in position and engage hook of arm with slot in pull rod
113. oe of float and surface of fuel bowl Fig 12 NEEDLE AND SEAT ACCELERATOR ASSEMBLY PUMP COVER AND LEVER FLOAT SPRING PRIMARY FUEL BOWL TOE OF FLOAT NP764A Fig 12 Checking Float Setting Primary and Secondary 14 50 FUEL SYSTEM HOLLEY 4160 If an adjustment is necessary bend float tang until correct clearance has been obtained 2 Invert the secondary fuel bowl and using a 17 64 inch drill shank or gauge measure the clear ance between heel of float and surface of fuel bowl Fig 12 If an adjustment is necessary bend float tang until correct clearance has been obtained Assembling Main Body 1 Place a new gasket on throttle body then lower main body Fig 13 down on throttle body aligning roll pin guides with openings in main body Be sure primary bores of throttle body are on the same side as primary venturi 2 Holding assembly together invert assembly and install attaching screws Tighten securely 3 Install balance tube into main body and install new rings and washers at each end Be sure rings are seated in recesses followed by washers 4 Install a new secondary metering body to main body gasket Fig 4 followed by metering body plate plate gasket and body Install clutch head screws and tighten securely Be sure the main metering restric tion ports are at the bottom 5 Position balance tube so that only 1 inch ex tends beyond the secondary metering body Fig
114. ondary Stop 68 Screws Secondary Throttle Valves 69 Throttle Valves Secondary 7 Fast dle Cam Lever 71 Fast Idle Cam 72 Retainer E Clip 73 Choke Diaphragm Link 74 Choke Diaphragm Assembly 75 Choke Vacuum Hose 76 Choke Diaphragm Bracket Screw 77 Secondary Diaphragm Cover Screw 78 Diaphragm Cover Machine 79 Secondary Diaphragm Return Spring 80 Secondary Diaphragm Assembly 81 Secondary Diaphragm Housing Machine 82 Secondary Diaphragm Housing Gasket 83 Secondary Diaphragm Assembly Screw 84 Throttle Connecting Rod Retainer Washer 85 Pump Operating Lever E Clip 86 Secondary Stop Screw 87 Throttle Stop Screw 88 Throttle Stop Screw Spring 89 Baffle 90 Limiter Cap 91 Bow Vent Valve Assy E C S as the throttle is opened this port is subject to mani fold vacuum which varies with changes in engine load This port in the throttle body is connected to the main body by a short vertical passage and then to a passage in the main metering body This passage leads to an outlet on the side of the main metering body which connects to a single flexible tube to the distributor SERVICE PROCEDURES Servicing Carburetor Dirt dust water and gummy deposits are some of the main causes for poor carburetor operation How ever proper cleaning and the installation of new parts where required will return the carburetor to its originally designed performance When overhauling
115. oration Control System E C S The function of the evaporation control system is to reduce the loss of fuel from the fue system to the atmosphere by evaporation and reduce the unburned hydro carbons emitted by the vehicle s engine When fuel evaporates from the carburetor or fuel tank it passes through vent hoses or tubes to the crankcase With the engine running vapors are purged from the crankease through the crankcase ventilation system as in the Cleaner Air System previously described The fuel tank contains a one gallon overfill limiter tank When the fuel tank is filled the overfill limiter tank remains essentially empty to allow for thermal expansion Each corner of the fuel tank is vented and each of the hoses from these vents are connected to the separator A tube from the separator leads to the breather cap Thus evaporated fuel vapor from the fuel tank flows through the separator to the engine crankcase and then through the crankcase ventilation system In addition the carburetor fuel bowl vent valve is also included by a tube from the vent valve to the breather cap or fuel pump 6 Cylinder en gines This completely seals the fuel system Idle Speed Adjustment Curb Idle To make the idle speed adjustment on carburetors secure an accurate ignition tachometer and a Sun Electric Combustion Vacuum Unit Model 80 Exhaust Condenser Model EC and Hose 669 14 or equivalent The above analyzer is recommended howev
116. out tank d Install new pump e Thaw lines and drain tank D Install new fuel pump g Install heat shield where lines or pump are near exhaust h Install new fuel pump i Install correct fuel pump j Install new filter a Tighten mounting bolts b Install new fuel pump c Install new spring 14 56 FUEL SYSTEM FUEL PUMP SERVICE PROCEDURES TESTING FUEL PUMP On Car If the fuel pump fails to supply fuel properly to the carburetor the following tests should be made be fore removing the fuel pump from the vehicle Pressure Test If leakage is not apparent test pump for pressure as follows 1 Insert a fitting in fuel line at carburetor Fig 3 2 Connect a 6 inch piece of hose between T fitting and gauge C 3411 The hose should not exceed 6 inches A longer hose may collect fuel and additional weight of fuel would be added to pressure of pump and result in an inaccurate reading 3 Vent pump for a few seconds this relieves air trapped in fuel chamber If this is not done pump will not operate at full capacity and low pressure reading will result 4 Connect a tachometer then start engine and run at 500 r p m The reading should be from 3 1 2 to 5 p s i and remain constant or return to zero very very slowly when engine is stopped An instant drop to zero indicates a leaky outlet valve If pressure is too low a weak diaphragm main spring or improper assembly of
117. p cylinder are vented through the area between the pump rod and pump plunger As the throttle lever is moved the pump link op erating through a system of levers and a pump over ride spring pushes the pump piston down Fuel is forced through a passage around the pump discharge needle valve and out the pump discharge jets which are drilled in the main body Automatic Choke System Fig 7 The automatic choke provides the richer fuel air mixture required for starting and operating a cold engine A bi metal spring inside the choke housing which is installed in a well in the intake manifold holds the choke valve in the closed position When the engine starts manifold vacuum is ap PUMP ASSEMBLY PUMP DISCHARGE PUMP OPERATING LINK RESTRICTION OVERRIDE SPRING PUMP DISCHARGE CUP CHECK NEEDLE PY867 Fig 6 Accelerating Pump System HOLLEY 2200 FUEL SYSTEM 14 17 plied to the choke diaphragm through a rubber hose from the throttle body to the choke diaphragm as sembly The adjustment of the choke valve opening when the engine starts and vacuum is applied to the choke diaphragm is called vacuum kick Manifold vacuum alone is not strong enough to provide the proper degree of choke opening during the entire choking period The impact of in rushing air past the offset choke valve provides the addi tional opening force As the engine warms up manifold heat transmit ted to the choke housing relaxes the bi metal sprin
118. plunger shaft using a scale Fig 15 This distance should be 7 16 inch If an adjustment is necessary bend the throttle connector rod at the lower angle using Tool T 109 baec 0 OR GAUGE PRESSURE UP ON CHOKE hu LEVER BEND UNLOADER TANG FOR CORRECT OPENING THROTTLE IN WIDE OPEN POSITION NR523A Fig 14 Checking Choke Unloader wide open kick TOP OF PLUNGER TO TOP OF AIR HORN BEND ACCELERATOR PUMP ROD AT ANGLE CURB IDLE SPEED ADJUSTING SCREW BACKED OFF TO ALLOW VALVES TO FULLY SEAT THROTTLE CLOSED PY729 Fig 15 Checking Accelerator Pump Adjustment 213 until correct travel has been obtained Secondary Throttle Lever Adjustment To check the secondary throttle lever adjustment block the choke valve in the wide open position and invert the carburetor Slowly open the primary throt tle valves until it is possible to measure between the lower edge of the primary valve and the bore op posite idle port Fig 16 Refer to Specifications The secondary valves should just start to open If an adjustment is necessary bend the secondary throttle operating rod at the angle using Tool T 109 213 until correct adjustment has been obtained With primary and secondary throttle valves in tightly closed position it should be possible to insert Tool T 109 29 020 wire gauge between positive closing shoes on the secondary throttie levers Fig 17
119. r a passage into a vertical channel where air is added from the idle air bleeds The fuel air mixture is then discharged through the primary transfer slots As the throttle valve is opened still wider and en gine speed increases the air flow through the car buretor is also increased This creates an increased vacuum in the venturi to bring the main metering system into operation The flow from the idle transfer system tapers off as the main metering systems begin discharging fuel The two systems are engineered to provide smooth gradual transition from idle to cruis ing speeds Main Metering System As the engine is running the intake stroke of each piston draws the air through the carburetor venturi and booster venturi The air passing through the re striction of the venturi creates a low pressure com monly called a vacuum The strength of this low pres sure is determined primarily by the velocity of the air flowing through the venturi This in turn is regulated by the speed and power output of the engine The difference between the pressure in the booster ven turi and the normal air pressure in the float chamber causes fuel to flow through the main metering sys tem Fig 6 At cruising speed the fuel flows from the float chamber through the main jet which measures or meters the fuel flow into the bottom of the main well The fuel moves up the main well past the main well air bleed hole in the side of the well Filtered a
120. rburetor or fuel tank The vapors pass through vent lines to the crankcase by way of the crankcase inlet air cleaner Since fuel vapors are two to four times heavier than air they settle to the bottom of the crankcase With the engine running the fuel vapors are purged from the crank case and together with the normal crankcase vapor are drawn via the crankcase ventilation system which is an existing part of the Cleaner Air System CAS into the base of the carburetor to be burnt by engine combustion The possible expansion of fuel in a full fuel tank due to a rise in temperature is allowed for by a 1 4 gallon over fill limiter tank inside the main fuel tank which fills much slower than the main tank When the main tank is filled it remains essentially empty to al low for thermal expansion Fig 1 CRANKCASE AIR CLEANER PCV VALVE THERMAL EXPANSION VOLUME TANK The loss of any fuel or vapor out of the filler neck is prevented by the use of a filler cap which will re lease only under significant pressure 1 2 to 1 psi or vacuum 1 4 to 1 2 psi This cap is identified by the words pressure vacuum and must be replaced by a similar unit if replacement is necessary in order for the system to remain effective Fig 1 Because the fuel tank is flat on top four vents are used one in each corner of the tank and are con nected to a vapor liquid separator by rubber hoses The vapor liquid separator is a piece of two inch st
121. relationship between choke valve thermostatic coil spring and the fast idle cam It should be checked and adjusted if necessary after carburetor assembly or as preparation of the choke system linkage before making the Vacuum Kick Cam Position or Unloader Adjustment These three adjust ments must and should be made after qualification of the choke control lever 1 Open the throttle to mid position 2 Close the choke valve by slight pressure on choke control lever 3 The top of choke rod hole in control lever should be 1 11 16 1 64 inch above choke assembly carburetor on engine or 1 23 32 1 64 inch above carburetor base Carburetor on bench Fig 18 4 Adjust if necessary by bending choke shaft rod at point indicated CAUTION Improper bending will cause binding of rod Test for free movement between open and closed TO ADJUST BEND TOP EDGE OF CHOKE AT THIS POINT X CONTROL ROD HOLE tx 11 16 1764 1 ex T ABOVE CHOKE gt lt ASSEMBLY CARBURETOR ON ENGINE 1 23 32 1 64 INCH CARBURETOR ON BENCH NR452A Fig 18 Qualifying Choke Control Lever A choke positions and rebend if necessary to eliminate any interferences Choke Unloader Adjustment wide open kick The choke unloader is a mechanical device to par tially open the choke at wide open throttle It is used to eliminate choke enrichment during cranking of an engine Engines which have been flooded or stalled
122. ring Coil Spring Setting e me m lee es 2 Notches Rich 2 Notches Rich After Approx 500 Miles If Necessary Without Air Conditioning With Air Conditioning FUEL PUMP 383 and 440 in Engine sensesosltisvR rere ue ince Carter Airtex pni MS 4589SA RD 267A Uere re SoS PT M em We ote we ena on ER E Diaphragm Diaphragm Number Of Valves coop I ob de Eua Rr 2 2 Driven DY ccd tener ep E Camshaft Camshaft Pump Pressure nace cece nna nnn 3 1 2 to 5 psi 3 1 2 to 5 psi
123. rottle shaft From closed to open posi tion they must operate smoothly without drag or sticking Hold throttle body up to a strong light The light which is visible around the outer diameter of valves in bore should be uniform Stake screws using a pair of pliers 5 Install idle mixture screws and springs in body The tapered portion must be straight and smooth If the tapered portion is grooved or ridged a new idle mixture screw should be installed to insure having correct idle mixture control DO NOT USE A SCREW DRIVER Turn screws lightly against their seats with fingers Back off the number of turns from the seat counted at disassembly Install new plastic caps with tab against stop Main Body 1 Invert main body and place a new gasket in position Place throttle body on main body and align Install attaching screws and tighten securely 2 Install accelerator pump discharge check needle in discharge passage Fig 15 Check accelerator pump fuel inlet and discharge systems as follows 3 Pour clean gasoline into fuel bowl approximate ly 1 inch deep Slide accelerator pump plunger into cylinder Raise plunger and press down lightly on plunger stem to expell all air from pump passage 4 Using a small clean brass rod hold discharge check needle down on its seat Again raise plunger and press downward No fuel should be emitted from pump discharge passage Fig 16 If any fuel does emit from discharge passage it in
124. s engine not running and move choke to closed position Release throttle first then release choke 2 When using an auxiliary vacuum source discon nect the vacuum hose from the carburetor and con nect it to the hose from the vacuum supply with a small length of tube to act as a fitting Removal of the hose from the diaphragm may require forces which damage the system Apply a vacuum of 10 or more inches of hose 3 Insert the specified drill see specifications be tween the choke valve and the wall of the air horn Fig 22 Apply sufficient closing pressure on the lever to which the choke rod attaches to provide a minimum choke valve opening without distortion of the diaphragm link Note that the cylindrical stem of the diaphragm will extend as an internal spring is compressed This spring must be fully compressed for proper measurement of the vacuum kick adjustment 4 An adjustment will be necessary if a slight drag is not obtained as the drill is being removed Shorten or lengthen the diaphragm link to obtain the correct choke opening Length changes should be made by carefully opening or closing the bend provided in the diaphragm link CAUTION DO NOT APPLY TWIST ING OR BENDING FORCE TO DIAPHRAGM 4 DRILL OR t GAUGE VACUUM DIAPHRAGM i S STEM RETRACTED Nate THIS POINT a oo PS LIGHTLY PRESS UP ON CHOKE CONTROL LEVER e TO VACUUM Y SUPPLY
125. sible to insert a number 72 drill shank 005 to 025 inch between bowl vent valve plunger stem and operating rod Fig 16 2 If an adjustment is necessary bend rod to change arc of contact with throttle lever using Tool T109 213 until correct clearance has been obtained Checking Accelerator Pump Lever Clearance To check accelerator pump lever clearance Fig 17 proceed as follows 1 With throttle valves wide open and the pump lever held down it should be possible to insert a 015 inch gauge between adjusting nut and lever 2 If an adjustment is necessary adjust pump over ride screw until correct clearance has been obtained 3 There must be no free movement of pump leverage when throttle is at curb idle DRILL OR GAUGE ADJUST VENT VALVE ROD HERE BOWL VENT VALVE Zi CARBURETOR SEAT ON IDENTIFICATION THROTTLE AIR HORN NUMBER VALVES IN CLOSED 5 CARBURETOR POSITION 768 BOWL YENT VALVE BOWL VENT VALVE OPERATING ROD PLUNGER STEM ECS CARBURETOR THROTTLE VALVES AT CLOSED CURB IDLE PY873 Fig 16 Checking Bowl Vent Valve Clearance C A S and E C S A 4THROTTLE VALVES PUMP OVERRIDE IN WIDE OPEN SPRING PUMP LEVER EX PUMP OVERRIDE HELD DOWN ADJUSTING SCREW NP769B Fig 17 Checking Accelerator Pump Lever Clearance Qualifying Choke Control Lever Adjustment of the choke control lever is necessary to provide correct
126. so equipped 5 Slide a new distributor ground switch insulated bushing into stop on main body with the notch aligned with raised portion of boss Force into position against stop 6 Place insulating washer over tangs on lead wire terminal then install curb idle speed screw with spring through terminal and washer 7 Turn screw into boss at the same time keep insulating washer aligned Assembling Secondary Diaphragm 1 Slide diaphragm into housing Fig 15 2 Position diaphragm so that the vacuum hole in housing is aligned with vacuum hole in diaphragm 3 Install diaphragm return spring with coiled end snapped over button in cover 4 Support diaphragm stem in order to keep dia phragm flat as spring and cover are installed 5 Align vacuum port in cover with port in housing HOLLEY 4160 FUEL SYSTEM 14 51 DIAPHRAGM COVER SPRING 2 d 1 Es SCREW VACUUM HOLE STEM al VACUUM HOLE NP767 Fig 15 Secondary Throttle Diaphragm Exploded View then carefully lower cover Install attaching screws and tighten securely 6 Check diaphragm by pressing in on stem and placing finger over port Diaphragm should stay in retracted position 7 Install a new gasket in vacuum passage recess in diaphragm housing then install secondary dia phragm on main body of carburetor and at the same time engage stem with secondary stop lever Install screws and tighten securely 8 Install pump lever on stub shaft and
127. st needle for sealing pour clean gasoline into primary fuel bowl through vent valve opening Push down on accelerator pump arm to expel air from the pump passages Using a small clean brass rod hold the discharge check needle firmly on its seat Again press down on pump arm No fuel should be emitted from the discharge passage Fuel leakage at the dis charge needle indicates the presence of dirt or a damaged check needle Clean again and install a new needle Retest for leakage If fuel continues to leak past discharge check needle attempt to reseat as follows With the discharge check needle installed insert a piece of drill rod down on the needle Lightly tap the drill rod with a hammer to form a new seat Remove and discard old needle and install a new one Retest as described previously If the service fix does not correct the condition a new carburetor will have to be installed 12 Install pump discharge nozzle gasket nozzle and mounting screw and gasket Tighten screw se curely Test nozzle operation Press pump lever down The two streams from the nozzle should be identical and should strike the two venturi in the same spot 13 Slide the bowl vent valve shaft down between fuel tube and carburetor body Hold in position then A install clamp after engaging stub end of spring in clamp Install retaining screw and tighten securely 14 Loosen choke valve attaching screws slightly 15 Tap lightly on choke valve to cen
128. stake Compress piston to be sure no binding exists If piston sticks or binds enough to hinder smooth operation a new pis ton should be installed 3 Slide accelerator pump plunger compression spring over plunger stem with small diameter toward SPECIAL TOOL TO SEAT PISTON RETAINING WASHER PY851 d Fig 17 Installing Vacuum Power Piston A plunger Install pump shaft in air horn Fig 8 4 As plunger is being installed in air horn slight ly tilt plunger to engage with plunger shaft 5 Install fuel inlet needle valve seat and gasket in air horn Tighten securely using a wide blade screwdriver Install fuel inlet needle in seat Fig 10 6 Install float in position then slide nylon fulcrum pin through float hinge to retain float Center fulcrum pin Fig 9 7 Install fuel baffle on bosses with slots engaged lugs Install attaching screw and tighten securely Fig 9 Measuring Float Setting The carburetors are equipped with a viton tipped fuel inlet needle The tip is flexible enough to make a good seal on the needle seat and to give increased resistance to flooding Care should be taken to perform this operation accurately in order to secure best per formance and fuel economy 1 To correctly set float height when carburetor is being overhauled proceed as follows 2 Invert air horn so that weight of float only is forcing needle against seat 3 Measure the clearance between top of float and
129. stall an approved exhaust gas analyzer for carburetor idle speed and mixture adjustment as described under Idle Speed Adjustment 3 With a narrow screw driver turn the two idle screws clockwise until they are both seated 4 Turn both idle screws 1 1 2 turns counterclock wise for 1 1 2 BBD carburetors and 2 to 3 turns counterclockwise for AVS carburetors as a starting point experience may dictate more or less turns as a rough setting but both screws should be turned equally 5 Start engine and set specified idle speed for en gines with 300 or more miles Set 75 rpm below speci fications if under 50 miles or 50 rpm below specifica tions if 50 to 300 miles are on engine 6 Observe air fuel ratio reading of exhaust gas analyzer Turn each screw 1 16 turn richer counter 14 4 clockwise and note change in air fuel meter reading From this point on follow instructions for idle setting until 14 2 air fuel ratio is obtained at approximate idle speed It is very important that both idle limiter Condition POOR IDLING POOR ACCELERATION CARBURETOR FLOODS OR LEAKS FUEL SYSTEM SERVICE DIAGNOSIS Possible Cause a Idle air bleed carbonized or of incor rect size b Idle discharge holes plugged or gummed c Throttle body carbonized or worn throttle shaft d Damaged or worn idle mixture needle e Low grade fuel or incorrect float level f Loose main body to throttle body screws g
130. stems Fuel from the bowls flow into the primary and the second ary metering bodies where the fuel is mixed with air for all phases of engine operation This type of metering provides for adequate diagnosis and easier servicing The two primary bores have one choke valve con nected to a well type automatic choke Each bore has its own venturi booster venturi main fuel discharge nozzle and throttle valve Additional fuel for acceleration is supplied by a diaphragm type mechanically operated pump which is located on the primary fuel bowl The pump is actuated from a cam on the primary throttle An over ride spring on the pump operating lever prolongs the discharge of fuel for smoother acceleration A power valve mounted on the primary metering body which is actuated by manifold vacuum delivers the additional fuel necessary for full power and high speed operation The larger volume of fuel in two separate bowls exposed to the cooling air stream is an effective means of reducing percolation and hard starting when the engine is hot An external vent on the primary bowl vents the primary fuel bowl when the throttle is closed The primary and or secondary bowls can be quickly removed to adjust the fuel level or change the fuel inlet valve without removing the carburetor from the engine Primary Fuel Inlet System All fuel first enters the primary fuel bowl which supplies the four basic metering systems with the re quired amount o
131. stment is to be made with engine run ning disconnect fast idle linkage to allow choke to close to the kick position with engine at curb idle If an auxiliary vacuum source is to be used open throt tle valves engine not running and move choke to closed position Release throttle first then release choke 2 When using an auxiliary vacuum source dis connect vacuum hose from carburetor and connect it to hose from vacuum supply with a small length of tube to act as a fitting Removal of hose from dia phragm may require forces which damage the sys DRILL OR GAUGE BEND FAST IDLE CONNECTOR ROD AT ANGLE FAST IDLE SPEED ADJUSTING SCREW ON SECOND STEP AND AGAINST FACE OF NEXT STEP OF FAST IDLE CAM PY502 LIGHT CLOSING PRESSURE gs AGAINST CHOKE LEVER Fig 12 Fast idle Cam Position Adjustment A tem Apply a vacuum of 10 or more inches of mer cury 3 Insert specified drill refer to Specifications be tween choke valve and wall of air horn Fig 13 Apply sufficient closing pressure on lever to which choke rod attaches to provide a minimum choke valve opening without distortion of diaphragm link Note that the cylindrical stem of diaphragm will extend as internal spring is compressed This spring must be fully compressed for proper measurement of vacuum kick adjustment 4 An adjustment will be necessary if a slight drag is not obtained as drill is being removed Shorten or lengthen diaphragm link to obt
132. t shell to determine if side of the float is parallel to outer cage of air horn casting Fig 8 2 If sides of float are not in alignment with edge of casting bend float lever by applying pressure to end of float shell with thumb To avoid damage to the float apply only enough pressure to bend the float lever 3 After aligning floats remove as much clearance as possible between arms of float lever and lugs of air horn To do this bend float lever The arms of float lever should be as parallel as possible to inner sur faces of lugs of casting Float Level Setting 1 With air horn inverted air horn gasket in place THESE SURFACES MUST BE PARALLEL WITH EDGE OF CASTING MINIMUM CLEARANCE WITHOUT BINDING GASKET BOWL VENT VALVE OPERATING LEVER BOWL VENT VALVE VALVE SPRING PY727 Fig 8 Checking Float Alignment 14 32 FUEL SYSTEM AVS and float needle seated slide float gauge refer to Specifications for carburetor being worked on be tween top of the float at outer end and air horn gas ket Fig 9 Float should just touch gauge T 109 107 2 Check other float in same manner If an ad justment is necessary bend float arm using Tool T 109 22 until correct clearance has been obtained After bending arm recheck the float alignment Float Drop Setting Float drop is the distance the floats move from the inverted air horn float level setting position to the airhorn in upright position 1
133. tainer and lift out floats and fulcrum pin 12 Remove step up piston and retaining screw and slide step up piston and rods out of well Fig 4 Lift out step up piston spring Remove step up piston gasket from bottom of well 13 Remove main metering jets Fig 5 14 Remove venturi cluster screws then lift ven turi cluster and gaskets up and away from main body Fig 6 Discard gaskets Do not remove idle orifice X STEP UP RODS BOTTOM OF WELL METERING JETS Y NR379 Fig 4 Removing or Installing Step Up Piston MAIN 258 METERING JETS 9 NR380A Fig 5 Removing or Installing Main Metering Jets tubes or main vent tubes from cluster They can be cleaned in a solvent and dried with compressed air 15 Invert carburetor and drop out accelerator pump discharge check ball and intake check ball The intake check ball is the largest 16 Remove screws that attach throttle body to main body Separate the bodies and discard gasket 17 Remove plastic limiter caps from idle air mix ture screws Be sure and count number of turns to seat the screws as the same number of turns from the seat must be maintained at installation Remove screws and springs from throttle body The carburetor now has been disassembled into three sub assemblies the air horn main body and throttle body and the components of each disassem bled as far as necessary for cleaning and inspection It is usually not advisa
134. talling Accelerator Pump Rocker Arm mar or scratch mating surface of air horn 14 Remove vacuum power piston from air horn using tool C 4141 Fig 11 This assembly is staked in position and care must be used at removal Remove staking using a suitable sharp tool 15 WARNING DO NOT ATTEMPT TO REMOVE MAIN WELL TUBES FROM AIR HORN These tubes are a pres fit in air horn and will be damaged if re moved They can be cleaned in a solvent and blown dry with compressed air If carburetor parts are cleaned in a basket be sure other carburetor parts are not striking these tubes 16 Using Tool TMC 36A remove main metering jets Fig 12 Number 65 located on throttle lever side of bowl number 63 on opposite side 17 Using Tool T109 73S remove power valve as sembly Fig 13 18 Invert main body and drop out accelerator pump discharge check needle from discharge pas CHOKE VALVE WIDE OPEN CHOKE LEVER FAST IDLE CAM i B FAST IDLE LOCKWASHER 5 CONNECTOR ROD PY837 Fig 3 Removing or Installing Fast Idle Connector Rod HOLLEY 2200 FUEL SYSTEM 14 19 SLOT IN LEVER CHOKE OPERATING LINK CHOKE DIAPHRAGM ATTACHING SCREWS b Td 37 PY838 S Fig 4 Removing or Installing Choke Diaphragm sage Fig 15 19 Remove fast idle cam retaining E clip then slide fast idle cam off stub shaft Fig 14 20 Invert main body and remove throttle body to main
135. ter valve in air horn Holding choke valve with the fingers tighten attaching screws securely Stake by squeezing with pliers 16 Engage fast idle cam with fast idle cam lever then slide assembly onto stub shaft positioning fast idle cam behind fast idle cam lever At the same time engage fast idle cam lever with choke rod Install E clip to secure Choke Vacuum Diaphragm Inspect the diaphragm vacuum fitting to be sure that the passage is not plugged with foreign material Leak check the diaphragm to determine if it has in ternal leaks To do this first depress the diaphragm stem then place a finger over the fitting to seal the opening Release the stem If the stem moves more than 1 16 inch in ten 10 seconds the leakage is excessive and the assembly must be replaced Install the diaphragm assembly on the carburetor as follows 1 Engage choke link in slot in choke lever 2 Place the diaphragm on the mounting surface Install and tighten the attaching screws securely 3 Inspect the rubber hose for cracks before plac ing it on the correct carburetor fitting Do not connect the vacuum hose to the diaphragm fitting until after the vacuum kick adjustment has been made 4 Install hot idle compensator valve gasket in position in recess in main body followed by valve Be sure valve is positioned with legs toward outside of main body Fig 5 Place cover over opening and install attaching screws Tighten securely If
136. the carburetor several items of importance should be observed to assure a good job 1 All parts should be carefully cleaned in a suit able solvent then inspected for damage or wear 2 Use air pressure only to clear the various ori fices and channels 3 Replace questionable parts with New Ones When checking parts removed from the carburetor it is at times rather difficult to be sure they are satis factory for further service It is therefore recom mended that in such cases New Parts be installed 4 Always use a complete repair kit when over hauling the carburetor Using the code number stamped on the airhorn adjacent to the fuel inlet refer to the parts catalog and order the correct repair kit for the carburetor being worked on DISASSEMBLING CARBURETOR To disassemble the carburetor Fig 1 for cleaning or overhaul proceed as follows 1 Install four elevating legs Tool T109 287S in 14 46 FUEL SYSTEM HOLLEY 4160 BOWL VENT VALVE ASSEMBLY PRIMARY BOWL ASSEMBLY PRIMARY METERING BODY BALANCE TUBE FUEL Gy f TRANSFER y i TUBE ACCELERATING PUMP OPERATING FUEL FUEL LEVER PUMP BOWL LEVER GASKET NP755B Fig 2 Removing or Installing Primary Fuel Bowl mounting flange holes in throttle body or use Carbu retor Stand C 3886 These tools are used to protect the throttle valves from damage and to provide a suit able base for working 2 Remove primary fuel bowl assembly b
137. the fitting to seal the opening Release the stem If the stem moves more than 1 16 inch in ten 10 seconds the leakage is excessive and the assembly must be replaced BBD FUEL SYSTEM 14 11 Install the diaphragm assembly on the airhorn as follows 1 Assemble diaphragm to air horn and tighten attaching screws securely 2 Install choke operating link in position between diaphragm plunger stem and choke lever Install clip to secure 3 Inspect rubber hose for cracks before placing it on correct carburetor fitting Fig 1 Do not connect vacuum hose to diaphragm fitting until after vacuum kick adjustment has been made See Carburetor Ad justments CARBURETOR ADJUSTMENTS It is very important that the following adjustments are made on a reconditioned carburetor and in the sequence listed Accelerator Pump 1 Back off idle speed adjusting screw Open choke valve so that fast idle cam allows throttle valves to be completely seated in bores Be sure that pump connector rod is installed in outer hole of throttle lever 2 Close throttle valves tightly Measure the dis tance between top of air horn and end of plunger shaft Fig 11 This measurement should be 1 inch 3 To adjust pump travel bend pump operating rod using Tool T 109 213 at lower angle of rod until correct setting has been obtained Fast Idle Speed and Cam Position Adjustment The fast idle engine speed adjustment should be made on the vehicle
138. the secondary throttle valves begin to open a vacuum is created in the secondary barrels first at the throttle valves and then as air flow increases at the throat of the secondary venturi This vacuum assists the secondary metering system to operate When engine speed is reduced venturi vacuum in the bores become weaker As the vacuum acting on the diaphragm is lessened the load on the diaphragm spring will commence closing the secondary valves The diaphragm spring is assisted by the design of the secondary valves Each secondary valve is slightly SECONDARY VENTURI PRIMARY DIAPHRAGM PICK UP A VENTURI CHAMBER Az PICK UP 2 222722 S NK DIAPHRAGM DIAPHRAGM ROD SECONDARY THROTTLE PLATE NP604B Fig 9 Secondary Throttle Operating System A offset When the valves are closing the combined force of manifold vacuum and the air stream has greater effect on the larger upstream area of the valves forcing the valves to a closed position The secondary valves are retained in the closed position when the primary valves are fully closed by the sec ondary throttle connecting rod This rod which is fastened to the primary throttle lever rides in a slot in the secondary throttle lever Secondary Fuel Metering Systems The secondary system is supplied with fuel from the secondary fuel bowl which receives its fuel through a connecting tube from the primary fuel inlet The secondary fuel bo
139. to secure specified A CHOKE VALVE WIDE OPEN FAST IDLE Be SPEED d ADJUSTING ADJUST SCREW TO OBTAIN FAST IDLE SPEED FAST IDLE CAM SCREW PY860 Fig 26 Fast Idle Speed Adjustment On Vehicle speed See Specifications 4 Stopping engine between adjustments is not necessary However reposition fast idle speed screw on cam after each speed adjustment to provide cor rect throttle closing torque To set idle speed on vehicles refer to Fuel System General Information Paragraph AVS SERIES CARBURETOR INDEX Pag Page Automatic Choke well type 1 idle Speed aee eere rere EE 35 Carburetor Adjustments 33 Secondary Throttle Lever 34 Accelerator Pump and Bowl Vent 34 35 Secondary Throttle Lockout 35 Air Valve Secondary 35 Cleaning Carburetor Parts 1 Bowl Vent Valve 35 Closed Crankcase Vent System Engine Group Choke Vacuum Kick 33 Disassembling Carburetor Choke Unloader Wide Open Kick 34 General Information 26 Fast Idle Cam Position 33 inspection and Reassembly 30 Fast Idle Speed On Vehicle 35 lt 66 GENERAL INFORMATION 383 C
140. tomatic Manual Automatic Engine Displacement Cu In 440 440 440 440 THROTTLE BORE Primary eR 1 11 16 1 11 16 1 11 16 1 11 16 Secondary 1 11 16 1 11 16 1 11 16 1 11 16 MAIN VENTURI Primary 1 7 16 1 7 16 1 7 16 1 7 16 MAIN JET Primary 101 101 101 101 Secondary 2 095 095 095 095 LOW SPEED JET Primary loe erra 69 029 69 029 65 035 69 029 STEP UP ROD 2 Stage Standard 16 575 16 575 16 617 16 575 ADJUSTMENTS Accelerator Pump top of plunger to air horn esses rere dsrs esau 7 16 7 16 7 16 7 16 Fast idle Cam Position drill size 50 50 50 50 Choke 1 4 1 4 1 4 1 4 Vacuum Kick drill size 2 1523 20 20 20 20 Bowl Vent Valve Setting 3 64 3 64 3 4 3 4 Fast Idle Speed r p m 1800 1800 2000 1800 Idle Speed r p m 800 800 900 800 Secondary Throttle Lever Adj 23 64 23 64 23 64 23 64 Secondary Throttle Lockout Adj 020 020 020 020 Float Setting 7132 7 32 7 32 7 32 Float Drop 1 2 1 2 1 2 1 2 Air Valve Spring Tension Vertical Turns 2 2 2 2 CHOKE Well Well Control Coil Sp
141. ture SPECIFICATIONS HOLLEY MODEL 4160 4 BARREL DOWNDRAFT CARBURETOR 5 E C S Model ere dM et Ege eae Fa ee t ooa ae R 4366A R 4360A Engine Displacement cu in 440 440 Transmission Type Automatic Automatic Throttle Bore Primary its le E EU UE Ene eder aee 1 9 16 1 9 16 Secondary 1 9 16 1 9 16 Main Venturi Primary avv ier ek dat ER 1 1 4 1 1 4 Secondary Cate ert 1 5 16 1 5 16 Main Metering Jet Standard 6 celu eher hee i er G s Sie NER S 64 64 T Size Lean ben epe emer eee xn ne bie els 63 63 2 Size Lean 5 000 10 000 ft 62 62 Adjustments Curb idle Speed 650 650 SPECIFICATIONS 14 65 1600 72 Drill 25 Drill 46 Drill 53 Drill 15 64 17 64 9 16 13 16 015 Min 65 Well Coil Spring 2 Notches Rich Power Valve Remover Installer Main Metering Jet Remover Installer Fast Idle Speed No 2 Step 1600 Bowl Vent Valve 5 64 Unloader Adjustment wide open throttle 25 Drill Vacuum Kick Adjustment 46 Drill Fast Idle Cam Position 53 Drill Float Setting Dry Prim rny cer eere elk peas eg sa mee ER RE 15 64 Secondary vac eee ind re rd 17 64 Float Setting Wet Primary E RUPEE EM 9 1
142. ubic Inch Engine The Carter four barrel carburetor models C A S Cleaner Air System AVS 4736S and AVS 4732S are used on the 383 cu in engines when the vehicles are equipped with automatic transmissions AVS 47328 is used on vehicles with air conditioning only and is equipped with a hot idle compensator valve This valve is a thermostatically operated air bleed to relieve an overrich condition at idle This condition is the result of excessive heat and resultant overrich mix tures Fig 1 The Carter four barrel carburetor model E C S Evaporation Control System AVS 47348 is used when the vehicle 15 equipped with an automatic transmis sion This carburetor is also equipped with a hot idle compensator valve as AVS 4732S above Fig 1 All of these carburetors are equipped with a distrib utor ground switch which retards the distributor when the carburetor is at curb idle for better emis sion control 440 Cubic Inch Engine The Carter four barrel carburetor models C A S Cleaner Air System 5 47375 AVS 4738S and AVS 4741S are used on the 440 cu in engines when the vehicles are equipped with a standard or auto matic transmission respectively AVS 4741S is used with air conditioning only and has a hot idle com AVS FUEL SYSTEM 14 27 CHOKE VALVE ACCELERATOR PUMP CLOSED PLUNGER STEM CRANKCASE CHOKE VALVE VENT TUBE FITTING ACCELERATOR PUMP PLUNGER LINK ACCELERATOR PUMP ROCKER ARM ACCELE
143. ury 3 Insert specified drill refer to Specifications be DRILL OR GAUGE REQUIRED EN LIGHT CLOSING PRESSURE ON CHOKE LEVER BEND LINK FOR ADJUSTMENT PY856 Fig 22 Vacuum Kick Adjustment A tween top of choke valve and wall of air horn Fig 22 Apply sufficient closing pressure on lever to which choke rod attaches to provide a minimum choke valve opening without distortion of diaphragm link Note that the cylindrical stem of diaphragm will extend as internal spring is compressed This spring must be fully compressed for proper measurement of vacuum kick adjustment 4 An adjustment will be necessary if a slight drag is not obtained as drill is being removed Shorten or lengthen diaphragm link to obtain correct choke open ing Length changes should be made carefully by bend ing open or closing the bend provided in diaphragm link CAUTION DO NOT APPLY TWISTING OR BENDING FORCE TO DIAPHRAGM 5 Reinstall vacuum hose on correct carburetor fitting Return fast idle linkage to its original condi tion if disturbed as suggested in Step No 1 6 Make following check With no vacuum applied to diaphragm the choke valve should move freely between open and closed positions If movement is not free examine linkage for misalignment or inter ferences caused by bending operation Repeat adjust ment if necessary to provide proper link operation Choke Unloader Wide Open Kick The choke unloader is a mec
144. vent tubes are clean in the primary venturi Place new primary venturi gaskets in position then install the primary venturi pump and choke side by lowering straight down on gaskets Fig 5 Install attaching screws and tighten securely 5 Install primary and secondary main metering jets using Tool T 109 58 Fig 4 Tighten jets se curely Install intake check 6 Install accelerator pump intake check ball using Tool T 109 59 7 Install hot idle compensator and gasket if so equipped Tighten screws securely Accelerator Pump Test 1 Pour clean gasoline mto carburetor bowl ap NS SECONDARY VALVE PRIMARY VALVE KF946C Fig 7 Throttle Valve Identification A proximately 1 2 inch deep Remove accelerator pump plunger from jar of gasoline Flex leather several times then slide into pump cylinder 2 Install accelerator pump discharge check needle in discharge passage Raise pump plunger and press lightly on plunger shaft to expel air from pump pas sages Using a small clean brass rod hold discharge check needle firmly on its seat Again raise plunger and press downward No fuel should be emitted from either the intake or discharge passage 3 If fuel does emit from intake passage remove intake check ball and reclean the passage Fuel leak age at discharge check needle indicates presence of dirt or a damaged check needle Clean again and then install a new check needle Retest for leakage 4
145. void breaking off in shaft Remove staking with a file 2 Slide damaged valves out of bores It should be noted at this time that the numbered side is on the bottom or carburetor mounting flange side and op ACCELERATOR posite the idle mixture screw ports PUMP SHAFT ACCELERATOR PUMP PLUNGER STEM PY841 4 j ADJUSTING TAB ig moving or installing Accelerator ins g FLOAT DROP Pump Plunger ACCELERATOR PUMP SHAFT FLOAT FULCRUM PIN NEEDLE VALVE AND SEAT TUBE FITTING SCREWDRIVER PUMP PLUNGER W SEAT AND GASKET SMALL END OF SPRING PY842 FUEL INLET NEEDLE PY844 Fig 8 Removing or Installing Accelerator Fig 10 Removing or Installing Float and Pump Shaft Needle Seat MAIN WELL TUBES DO NOT REMOVE SERVICED IN AIR HORN CASTING ONLY SPECIAL TOOL VACUUM POWER PISTON PY845 PUMP DISCHARGE CHECK NEEDLE MAIN METERING JET 63 METERING JET 65 POWER VALVE PY846 Fig 12 Removing or Installing Main Metering Jets CLEANING CARBURETOR PARTS Refer to General Information Section at front of Fuel System for cleaning instructions SPECIAL TOOL POWER VALVE PY847 Fig 13 Removing or Installing Power Valve HOLLEY 2200 FUEL SYSTEM 14 21 STUB SHAFT E THROTTLE WIDE OPEN Fig 14 Removing or Installing Fast Idle Cam INSPECTION AND R
146. wl is equipped with a fuel inlet assembly which regulates the flow of fuel into the bowl the same as the primary fuel bowl The sec ondary fuel inlet system must maintain a specified level of fuel as the two secondary fuel systems are calibrated to deliver the proper mixture only when the fuel is at this level As the valves begin to open the fuel flows through the secondary metering restrictions into the idle well Fig 10 A secondary fixed curb idle discharge passage sup plies fuel directly to the intake manifold thus allow ing a smoother idle When the secondary throttle valves are opened further the pressure differential causes the secondary main metering system to begin functioning Automatic Choke The automatic choke supplies enriched fuel air mix ture for starting and operating a cold engine Fig 11 Most of the fuel from the carburetor of a cold engine is liquid This fuel in liquid form burns slowly and incompletely Power loss and stalls result The choke valve supplies the extra fuel by restricting air flow CODE IDLE AIR BLEED um SAM MAIN AIR BLEED i IDLE RESTRICTION AIRES Es iS XS 51 2 TRANSFER TUBE f N d MAIN METERING CS RESTRICTION IDLE WELL NR558A AIR 2210 METERING i CONSTANT IDLE TRANSFER SLO DISCHARGE Fig 10 5 Fuel Metering System HOLLEY 4160 FUEL SYSTEM 14 43 during cranking and warm up Vacuum created by the restrict
147. y sliding straight off balance tube Fig 2 3 Remove primary metering body by sliding Straight off balance tube Fig 3 Remove plate to body gasket 4 Remove accelerating pump operating lever clip and slide lever assembly off stub shaft Remove adjusting nut spring and screw 5 Remove fuel transfer tube and rings Fig 8 6 Remove secondary fuel bowl assembly 7 Using a clutch head screwdriver Tool CL 13 remove clutch head screws carefully work secondary metering body plate and gaskets off balance tube Fig 4 8 Remove balance tube washers and rings by sliding out of main body either end 9 Disconnect choke diaphragm hose from throttle body fitting then remove diaphragm assembly at the same time disengaging link from fast idle cam lever FUEL TRANSFER TUBE GASKET NP756C Fig 3 Removing or Installing Primary Metering Body and Plate CARBURETOR GASKET GASKET T aa BALANCE TUBE SECONDARY CLUTCH HEAD NP757C METERING BODY SCREW Fig 4 Secondary Metering Body Plate and Gaskets 10 Remove E clup that retains fast idle cam lever and cam Slide lever and cam off stub shaft and at the same time disengage choke rod from cam lever Note position of fast idle cam to cam lever 11 Remove secondary diaphragm attaching screws and remove diaphragm assembly Disengage di

Group 14 - Fuel System

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