SERVICE MANUAL UPDATE-REVISED CAM GEAR REPLACEMENT PROCEDURE
Model and Year: 1982-88 CELEBRITY WITH 2.5L (VIN R) ENGINE
This bulletin supersedes current and past service manual procedures and supersedes Chevrolet Dealer Service Bulletin Number 85-101, dated 07/85. All copies of 85-101 should be discarded.
A set of revised service procedures has been developed for replacement of camshaft timing gears. The revised methods do not require the complete removal of the engine from the vehicle. Cam gear replacement is generally accomplished by partially lowering the engine/cradle assembly to gain access to the cam gear.
This bulletin contains a complete procedure for servicing cam gears on Celebrity models with 2.5L engines.
NOTICE: SEE APPROPRIATE SERVICE MANUAL SECTION FOR FASTENER TORQUE SPECIFICATIONS.
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TOOLS REOUIRED
J28467-A Engine Support Fixture J24420-B Cam Gear Removal Tool J25033-B Cam Gear Installation Tool J34995 Crankshaft Front Cover Oil Seal Installer J8001 Universal Dial Indicator w/Magnetic Base
REMOVE OR DISCONNECT
1. Negative battery cable. 2. Drain coolant. 3. Belt tensioner and belt, or drive belts, as applicable. 4. Upper engine torque strut. 5. Timing pointer plate (as applicable). 6. Both forward hood bumpers. 7. Install engine support fixture - J28467-A per Service Manual. 8. Raise vehicle. 9. Both front wheels. 10. Drain engine oil (remove oil filter). 11. Steering shaft pinch bolt at steering gear. 12. Right front lower ball joint. 13. Right front brakeline-to-body bracket. 14. Right front wheelhouse engine splash shield. 15. Flywheel/flexplate cover. 16. Crankshaft pulley (have assistant hold flywheel). 17. Frame (cradle) bolts and insulators (4). 18. Lower vehicle. 19. Timing gear cover bolts (8). 20. Lower the passenger side of the cradle/powertrain assembly 4 inches with support fixture (may require lowering of driver's side) . 21. Raise vehicle. 22. Timing gear cover - do not distort.
CLEAN:
- Timing gear cover and engine sealing surfaces.
23. Align crankshaft/camshaft timing marks on gears. 24. Drill and tap the existing camshaft center hole (8mm drill, 1/2 inch deep).
CAUTION:
WEAR SAFETY GIASSES TO AVOID EYE DAMAGE.
USE CARE WHEN DRILLING AND TAPPING CAM GEAR TO AVOID DAMAGE TO THE CAMSHAFT.
IMPORTANT: COVER OIL PAN OPENING WITH RAGS TO PREVENT CHIPS FROM FALLING INTO PAN.
25. Tap the 8mm hole with a 3/8-16-NC bottoming tap.
IMPORTANT: AVOID BUILD-UP OF CHIPS. BACK OUT THE TAP EVERY FEW TURNS AND REMOVE CHIPS.
26. Center punch and drill (2) 3mm pilot holes in the metal hub of the cam gear (180 degrees apart).
IMPORTANT: USE CARE TO AVOID DRILL WANDER THAT COULD DAMAGE CAMSHAFT.
27. Enlarge pilot holes with 5.5mm drill; 1/4 inch deep. 28. Tap 5.5mm holes with 1/4-28-NF bottoming tap.
29. Drill a hole no larger than lmm (.040 in.) in the front oil gallery plug. This provides improved lubrication to the timing gears.
CLEAN:
- Oil pan of debris.
30. Remove cam gear with J24420-B - do not move cam or crank.
INSPECT:
- Thrust plate for scuffing and/or grooving. If evident, install new thrust plate, spacer ring, and key. Thrust plate-to-block bolts torque - 10 Nm. (9 0 lb . in. ) .
IMPORTANT: LUBRICATE FRONT THRUST PLATE SURFACE WITH CLEAN ENGINE OIL.
INSTALL OR CONNECT
1. Cam gear using J25033-B - align timing marks.
MEASURE:
- Camshaft end play using dial indicator - J8001 or equivalent. Push cam gear onto camshaft until camshaft end play is in the range of .0015 in. to .0050 in. (.04mm to .13mm).
2. J34995 into front cover - lubricate seal lip with clean engine oil. 3. Apply RTV sealant to timing gear cover sealing surfaces. 4. Timing gear cover to engine. 5. Brakeline bracket to frame. 6. Crank pulley and bolt. 7. Flywheel/flexplate cover and bolts. 8. Lower vehicle. 9. Raise frame assembly with support fixture. 10. Install (4) frame (cradle) bolts finger tight. 11. Remove engine fixture. 12. Raise vehicle. 13. Cradle bolts. 14. Lower ball joint; use new pinch bolt. 15. Steering shaft pinch bolt. 16. Engine splash shield. 17. Both front wheels. 18. Lower vehicle 19. Front hood bumpers. 20. Engine torque strut. 21. Tensioner - as applicable.
CLEAN:
- Tensioner and block sealing surfaces. Do not remove the existing liquid injection molded (LIM) sealing bead. Apply RTV around LIM ring.
22. Timing pointer plate (as applicable). 23. Accessory drive belt (s). 24. Engine oil (replace oil filter). 25. Coolant. 26. Negative battery cable. 27. Check toe-in and adjust if necessary.
INSPECT:
- For oil and coolant leaks with engine running at operating temperature and for proper completion of repairs.
WARRANTY INFORMATION:
Labor Operation Number: J0840
MODEL/YRS MODEL/YRS 1987-88 1982-86 ------- ------- LABOR TIME: 3.9 4.2
ADD:
Replace Crank Gear .1 .1 Locking Wheel Cover/Nuts .2 .2 Air conditioning .1
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that 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 a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.
