Home

#99-06-01-003: Engine Bearing Knock Noise (Re

1. 0025 in Retain upper bearing shell number 5 main bearing production 0 001 in undersized Remove number 5 lower main bearing shell from the cap and discard Install 0 002 in undersize bearing insert P N 12329792 in the number 5 cap LOWER HALF ONLY 10 11 9 4 Apply a liberal coating of clean engine oil to the bearing surface 9 5 Reinstall crankshaft bearing cap bolts and studs to the engine block making sure that the caps bolts and studs retain their original position and orientation Tighten 1 Tighten the crankshaft bearing cap bolts and studs on the first pass to 20 N m 15 Ib ft 2 Tighten the crankshaft bearing cap bolts on the final pass to 73 degrees using the J 36660 A 9 6 Remove the screw jack used for crankshaft support 9 7 Go to Step 12 Crankshaft main Bearing Service for Locations Number 2 3 and 4 0 0025 in or greater but less than 0 0030 in 10 1 Lower jack stand from crankshaft allowing the crankshaft to be supported by the numbers 1 2 3 and 4 crankshaft main bearings 10 2 Insert J 8080 into the crankshaft number 5 main bearing oil hole and rotate the crankshaft to turn the upper bearing insert out of the engine block Discard the removed upper bearing insert 10 3 Insert J 8080 into the crankshaft number 5 main bearing oil hole 10 4 Procure the crankshaft number 5 main bearing 0 0020 in undersize bearing upper insert from kit P N 12329792 apply clean engine oil to the
2. 3 Final Pass four bolt main bearing caps Tighten the crankshaft bearing cap OUTBOARD bolts and studs to 43 degrees using the J 36660 A 4 Final Pass four bolt main bearing caps Tighten the crankshaft bearing cap INNER bolts and studs to 73 degrees using the J 36660 A 12 4 Go to Step 13 Connecting Rod Bearing Service 13 Connecting Rod Bearing Service Important Do not disassemble connecting rod bearing caps for bearing clearance measurement The design of the connecting rods in these engines does not permit accurate bearing clearance measurements when the connecting rod caps are disassembled from the connecting rods Conventional methods of measuring bearing clearance such as Plastigauge cannot accurately be performed on these engines GM Powertrain has developed a new accurate and time efficient means for measuring connecting rod bearing clearance without disassembly of the connecting rods In early 1999 SPX Kent Moore Tool will be releasing a new essential tool to dealers in the United States to facilitate this new procedure Until this new essential tool is released Contact SPX Kent Moore Tool at 1 810 345 2233 who will then arrange for dealers to borrow a special connecting rod bearing clearance measuring tool and associated instruction sheet and video Using this methodology measure and refit connecting rod bearing inserts in each of the connecting rods Use undersize connecting rod bearing inserts listed in the table bel
3. 99 06 01 003 Engine Bearing Knock Noise Re suppport Crankshaft Select fit Rod Bearings Mar 29 1999 Subject Engine Bearing Knock Noise Re support Crankshaft Select fit Undersize Connecting Rod Bearings Models 1999 Cadillac Escalade 1996 99 Chevrolet and GMC C K G P Models with 5 0L or 5 7L Engine VINs M R RPOs L30 L31 Important GM Canada Dealers require prior DSM authorization to apply this bulletin Condition Some customers may comment about an engine knocking noise Cause A condition may exist in some engines where the crankshaft is NOT being evenly supported by all five crankshaft bearing inserts In these engines the number 1 2 3 and 4 crankshaft bearing inserts are supporting the crankshaft and the number 5 crankshaft journal rear has excessive clearance relative to the number 5 crankshaft main bearing cap insert In this condition the crankshaft flexes under load and pounds on the lower number 5 crankshaft main bearing insert creating the knocking sound The engines were originally built with 0 0006 in undersize crankshaft main bearing inserts in the number 2 3 and 4 crankshaft main bearing locations and 0 001 in undersize insert in the number 5 crankshaft main bearing location The service procedure listed below addresses the above condition by lowering the crankshaft at the number 2 3 and 4 crankshaft main bearing positions increased crankshaft main bearing size of
4. bearing insert P N 12561191 in the number 5 cap 11 4 LOWER HALF ONLY Apply a liberal coating of clean engine oil to the bearing surface reinstall crankshaft bearing cap bolts and studs to the engine block making sure that the caps bolts and studs retain their original position and orientation Tighten 1 2 11 5 11 6 Tighten the crankshaft bearing cap bolts and studs on the first pass to 20 N m 15 Ib ft Tighten the crankshaft bearing cap bolts on the final pass to 73 degrees using the J 36660 A Remove the screw jack used for crankshaft support Go to Step 12 Crankshaft main Bearing Service for Locations Number 2 3 and 4 12 Crankshaft main Bearing Service for Locations Number 2 3 and 4 Important Do not remove the number 1 front main bearing cap 12 1 Mark and remove the bearing caps from crankshaft bearings number 2 3 and 4 12 2 Install new bearing inserts P N 10120990 standard size lower inserts only to the numbers 2 3 and 4 crankshaft bearing caps Important Bearing caps must be installed in the proper location and orientation or engine damage could result 12 3 Apply a liberal coating of clean engine oil to the bearing surface and reinstall the bearing cap and bolts Tighten 1 Tighten the bearing cap bolts on the first pass to 20 N m 15 Ib ft 2 Final Pass two bolt main bearing caps Tighten the bearing cap bolts on the final pass to 73 degrees using the J 36660 A
5. the lower crankshaft main bearing inserts and raising the number 5 lower crankshaft main bearing insert undersized insert in order to properly contact the number 5 crankshaft journal surface These engines may also exhibit a connecting rod knocking sound In these engines the connecting rod knocking sound is caused by excessive connecting rod bearing clearance A customer concern vehicle may exhibit one or both of the above stated conditions Correction Follow strategy based diagnostics for engine noise listed in the front of Section 6 of the Service Manual Some additional key points Rod Bearing Knock Occurs on initial engine start up and can also be heard as high as 1 500 1 800 RPM Rod bearing knock typically diminishes or completely goes away when the engine reaches normal operating temperature Crankshaft Bearing Knock Crankshaft main bearing knock sounds deeper in the engine and also sounds more muffled There are two different types of crankshaft bearing knock e Short duration cold knock typically occurs for 1 5 seconds on engine cold start up only and almost always occurs on vehicles equipped with an engine oil cooler e Hot knock occurs less frequently typically occurring in very hot ambient temperatures and can be heard up to 2 000 RPM Technicians can increase the likelihood of reproducing bearing induced knock sounds by slightly depressing the accelerator pedal while starting the engine Cranksh
6. 2 kit LOWER P N 10120990 use 1 2 kit Do Not Service Parts Information Crankshaft bearing insert Number 5 rear 0 002 In 12329792 1 kit services 1 journal undersize Number 5 rear 0 004 in 1 kit services lower bearing Grp 0 213 undersize 12561191 shell only Intermediate 2 10120990 1 kit services 1 journal 3 std Connecting Rod 0 0010 in undersize 12523925 1 kit services 1 journal Bearing Insert Grp 0 616 0 0020 in undersize 12329426 1 kit services 1 journal Parts are currently available from GMSPO Warranty Information For vehicles repaired under warranty use Labor Operation J1150 Use published labor time GM bulletins are intended for use by professional technicians NOT a do it yourselfer may occur on some vehicles or to provide information that could assist in the proper service of a vehicle Properly trained technicians have the equipment tools safety instructions and know how to do a job properly and safely If a condition is described DO NOT assume that the bulletin applies to your vehicle or that your vehicle will have that condition See your GM dealer for information on whether your vehicle may benefit from the information They are written to inform these technicians of conditions that
7. aft Bearing Service Procedure Important The repair procedure must be performed using all steps addressing both the crankshaft bearings and connecting rod bearings in order to ensure the effectiveness of the repair procedure 1 Remove the oil pump Refer to Oil Pump Replacement in Engine Mechanical section of the Vehicle Service Manual Important Do not loosen or attempt to service the number 1 front crankshaft main bearing cap or the number 1 crankshaft main bearings 2 Mark the number 2 3 4 and 5 crankshaft main bearing caps with position and direction The crankshaft main bearing caps MUST be reinstalled in the original position and direction 3 Support the crankshaft using a screw type jack and a block of wood 3 1 Position the screw type jack and the block of wood at the center of the crankshaft in order to properly support the crankshaft 3 2 Turn the screw of the screw type jack until the crankshaft is firmly seated against the crankshaft main upper bearings 4 Remove the number 5 crankshaft main bearing cap bolts and the number 5 crankshaft main bearing cap with the crankshaft main lower bearing 5 Using green plastigauge designed for measuring 0 001 0 003 in of clearance lay two pieces 2 inches in length laterally along the number 5 lower crankshaft main bearing 1 4 inch inboard from the insert outer edges Re install the bearing cap Tighten 1 Tighten the bearing cap bolts on the first p
8. ass to 20 N m 15 Ib ft 2 Tighten the bearing cap bolts on the final pass to 73 degrees using the J 36660 A 6 35 mm 0 25 in 6 Remove the number 5 cap and measure the plastigauge using the inch scale All 1996 99 5 0L L30 and 5 7L L31 engines were built with 0 001 in undersized number 5 crankshaft bearing inserts 7 If the measurement is e Less than 0 0020 in Go To Step 8 e 0 0020 in or greater but less than 0 0025 in Go To Step 9 e 0 0025 in or greater but less than 0 0030 in Go To Step 10 e 0 0030 in or greater Go To Step 11 9 1 9 2 9 3 8 Less than 0 0020 in 8 1 Retain production 0 001 in undersize upper and lower bearing inserts at the number 5 crankshaft bearing position 8 2 Clean any and all plastigauge material and residue from the bearing inserts 8 3 Liberally coat bearing inserts with clean engine oil and reinstall crankshaft bearing caps and bolts 8 4 Reinstall crankshaft bearing cap bolts and studs to the engine block making sure that the cap bolts and studs retain their original position and orientation Tighten 1 Tighten the crankshaft bearing cap bolts and studs on the first pass to 20 N m 15 Ib ft 2 Tighten the crankshaft bearing cap bolts on the final pass to 73 degrees using the J 36660 A 8 5 Remove Screwjack used for crankshaft support 8 6 Go to Step 12 Crankshaft main Bearing Service for Locations Number 2 3 and 4 9 0 0020 in or greater but less than 0
9. bearing insert and insert the plain end without the bearing tang of the bearing shell between the crankshaft and the notched side of the engine block web 10 5 Rotate the crankshaft to roll the upper bearing insert into the engine block 10 6 Remove the J8080 from the crankshaft 10 7 Remove the number 5 lower main bearing shell from the cap and discard 10 8 Install 0 002 in undersize bearing lower insert from kit P N 12329792 in the number 5 cap 10 9 Apply a liberal coating of clean engine oil to the bearing surface 10 10 Reinstall crankshaft bearing cap bolts and studs to the engine block making sure that the caps bolts and studs retain their original position and orientation Tighten Tighten the crankshaft bearing cap bolts and studs on the first pass to 20 N m 15 Ib ft 10 11 Thrust the crankshaft rearward in order to set and align the crankshaft thrust bearings and the crankshaft bearing caps 10 12 Thrust the crankshaft forward in order to align the rear faces of the crankshaft thrust bearings Tighten Tighten the crankshaft bearing cap bolts on the final pass to 73 degrees using the J 36660 A 10 13 Go to Step 12 Crankshaft main Bearing Service for Locations Number 2 3 and 4 0 0030 in or greater 11 1 Retain upper bearing shell number 5 main bearing production 0 001 in undersized 11 2 Remove number 5 lower main bearing shell from the cap and discard 11 3 Install 0 004 in undersize
10. measurements 13 4 Screw the attaching stud of the flexible dial indicator support into a convenient oil pan rail bolt hole Position the dial indicator so that the stylus is centered on the connecting rod cap and lock the flexible dial indicator support into position 13 5 Using the fine adjustment feature on the flexible dial indicator support knob near dial indicator adjust so that the dial indicator needle has sufficient travel in both directions to take an accurate measurement 13 6 Load the connecting rod in the upward direction of piston travel and zero the test indicator Load the connecting rod in the reverse direction and record the reading off the indicator Repeat this process 2 3 times applying consistent pressure in each direction to ensure the oil film is pushed out of the journal Record these readings 13 7 In order to accurately determine which rod or rods is causing the knock perform this procedure on all eight rod assemblies 13 8 Analyze the measurements from all eight rods Select bearings that will put the total clearance for each rod at 0 001 0 002 inch clearance Install new upper and lower bearing inserts as required being sure to lubricate liberally with clean engine oil Tighten 1 Tighten the rod bearing caps on the first pass to 27 N m 20 Ib ft 2 Tighten the rod bearing caps on the final pass to 55 degrees 13 9 Reinstall the oil pump to the crankshaft rear bearing cap Tighten 1 Tighten
11. ow to selectively fit each connecting rod bearing for a clearance of 0 001 0 002 in 13 1 Center the connecting rod journal to be worked on in the 6 o clock position Using screw jacks lock the crankshaft in position as close to the bearing being worked on as possible Tighten the screw jack sufficiently to displace the oil film from the upper main bearings To avoid damage to the crankshaft use a cushioning material such as a block of wood between the crankshaft and jack 13 2 Check rod bearing clearance using a bearing loading and unloading tool and test indicator capable of measuring 0 0001 inch increments Important A test indicator is required for this procedure do not substitute a dial indicator A dial indicator uses a plunger and will not provide repeatable results Likewise Plastigauge is not effective in this repair and should not be used for this procedure To ensure this analysis technique will be accurate do not disassemble the rod assembly 13 3 With the rod bearing to be worked on in the 6 o clock position install the test indicator Tighten the thumb screw until snug Install the base bracket to the oil pan rail and center it so that the handle can move freely in the slot provided The link pin on the connecting rod bearing clearance measuring tool should line up with the centerline of the connecting rod and have a push pull action in line with the connecting rod This alignment is crucial for accurate and repeatable
12. the oil pump bolt on the first pass to 20 N m 15 Ib ft 2 Tighten the oil pump bolt on the final pass to 65 degrees using the J 36660 A 14 Reassemble as required Use Service Manual procedure Re install Oil Pan Crankshaft Greater Number 5 than 0 0025 in main Bearing 0 002 in and greater Clearance per but less but less Plastigauge 0 002 in or than than 0 0030 in Measurement less 0 0025 in 0 0030 in or greater Number 5 rear Number 4 Number 3 Number 2 Number 1 front UPPER Do Not Service LOWER Do Not Service UPPER Do Not Service LOWER P N 10120990 use 1 2 kit UPPER Do Not Service LOWER P N 10120990 use 1 2 kit UPPER Do Not Service LOWER P N 10120990 use 1 2 kit Do Not Service UPPER Do Not Service LOWER 0 002 us P N 12329792 use 1 2 kit UPPER Do Not Service LOWER P N 10120990 use 1 2 kit UPPER Do Not Service LOWER P N 10120990 use 1 2 kit UPPER Do Not Service LOWER P N 10120990 use 1 2 kit Do Not Service UPPER 0 002 us P N 12329792 LOWER 0 002 us P N 12329792 use 1 kit UPPER Do Not Service LOWER P N 10120990 use 1 2 kit UPPER Do Not Service LOWER P N 10120990 use 1 2 kit UPPER Do Not Service LOWER P N 10120990 use 1 2 kit Do Not Service 0 004 us P N 12561191 use 1 kit P N 10120990 use 1 2 kit LOWER P N 10120990 use 1

#99-06-01-003: Engine Bearing Knock Noise (Re

Contents

Download Pdf Manuals

Related Search

Related Contents