SERVICE MANUAL UPDATE SEC. 6A ENGINE MECHANICAL-FLYWHEEL

SUBJECT: SERVICE MANUAL UPDATE - SECTION 6A - ENGINE MECHANICAL FLYWHEEL REPLACEMENT (REVISED PROCEDURE)

MODELS AFFECTED: 1989-91 CENTURY WITH 3300 V6 AND 4T60 TRANSAXLE

SERVICE MANUAL UPDATE - SECTION 6A

The following Flywheel Replacement procedure updates and replaces the current procedure found in the 1989 through 1991 Century Service Manual Section 6A.

FLYWHEEL REPLACEMENT

Figures 1 through 7

Tools Required:

J 28467-A Engine Support FIXTURE J 34754 Drive Axle Seal Protector J 37292-B Axle Seal Protector J 36660 Torque/Angle Meter (1991 Model)

Remove or Disconnect

1. Negative battery cable 2. Air cleaner and duct assembly 3. T.C.C. switch electrical connector 4. A/C low pressure switch electrical connector 5. Neutral start switch electrical connector 6. T.V. cable from throttle body and transaxle 7. Shift control cable from transaxle mounting bracket and lever 8. Vacuum modulator line from modulator 9. Three upper transaxle bolts from engine and ground wires 10. Steering shaft pinch bolt. Refer to Power Steering Gear and Pump (Section 3B1). 11. Install J 28467-A 12. Raise vehicle and suitably support. Refer to General Information (Section 0A). 13. Front tire and wheel assemblies. Refer to Tires and Wheels (Section 3E). 14. Engine splash shields 15. Pinch bolts from control arms. Refer to Front Suspension (Section 3C). 16. Stabilizer shaft bolts and reinforcement plates from frame 17. Stabilizer shaft nuts and bracket-from control arm. Separate stabilizer shaft from control arm. 18. Using a 7/16 inch drill bit, drill through two spot welds located between front and rear holes of left front stabilizer shaft mounting. 19. Front and rear transaxle mounting nuts 20. Power steering cooler line bolts 21. Right frame to left frame retaining bolt. Position jack stand under frame for support. Refer to Frame and Underbody (Section 10-3) 22. Loosen two right frame mounts and discard bolts. 23. Two left frame bolts from frame 24. Left frame assembly 25. Transaxle mount retaining bolts from transaxle case. Remove mount. 26. Two flywheel inspection covers 27. Torque converter bolts

NOTICE: DRIVE AXLE SEAL PROTECTOR J 34754 SHOULD BE MODIFIED AND INSTALLED ON ANY DRIVE AXLE PRIOR TO SERVICE PROCEDURES ON OR NEAR THE DRIVE AXLE. FAILURE TO OBSERVE THIS MAY RESULT IN SEAL DAMAGE AND POSSIBLE JOINT FAILURE. REFER TO DRIVE AXLE (SECTION 4D) FOR INFORMATION ON J 34754 AND FOR PROPER DRIVE AXLE REMOVAL AND HANDLING PROCEDURES.

28. Drive axles from transaxle. Refer to Drive Axle (Section 4D). 29. Transaxle support bracket bolts from transaxle 30. Vehicle speed sensor electrical connector from transaxle 31. Transaxle cooler lines 32. Install transaxle jack 33. Rear transaxle bolts from engine 34. Remaining transaxle bolts 35. Transaxle 36. Flywheel attaching bolts and flywheel. Discard bolts.

Inspect Flywheel, if cracked, badly worn or broken teeth, replace. Crankshaft and flywheel mating surfaces for burrs. Remove as required.

Install or Connect

1. Flywheel and new attaching bolts. Apply thread lock compound GM P/N 12345493 or equivalent to bolt threads before assembly.

Tighten (1989-90 Models) Bolts to 82 N.m (61 lbs. ft.) (1991 Models) Bolts to 15 N.m + 50- (11 lbs. ft.+ 50-) Use J 36660 Torque/Angle Meter.

2. Dial indicator on engine block and check flywheel runout at three attaching bosses.

IMPORTANT

The crankshaft end-play must be held in one direction during this check. Run-out should not exceed 0.381 mm (0.015 in.).

3. If run-out exceeds 0.381mm (0.015 in.) attempt to correct by tapping high side with mallet. 4. If condition cannot be corrected, replace flywheel. 5. Transaxle 6 Remaining transaxle bolt

Tighten Bolts to 75 N.m (55 lbs. ft.).

7. Remove transaxle jack 8. Transaxle cooler lines 9. Rear transaxle to engine bolt.

Tighten Bolts to 55 N.m (41 lbs. ft.)

10. V.S.S. electrical connector to transaxle 11. Transaxle support bracket and bolts to transaxle

Tighten Bolts to 43 N.m (32 lbs. ft.)

12. Drive axles to transaxle. Refer to Drive Axle (Section 4D). 13. Converter to flywheel bolts

Tighten All bolts to 62 N.m (46 lbs. ft.). Retorque the first bolt after all three have been tightened.

14. Two flywheel inspection covers

Tighten Bolts to 10 N.m (89 lbs. in.)

15. Transaxle mount and transaxle mounting bolts to transaxle case

Tighten Bolts to 55 N.m (41 lbs. ft.)

16. Left frame assembly 17. Left frame assembly bolts to body

Tighten Bolts to 54 N.m (40 lbs. ft.)

18. Right frame bolts to body

Tighten Bolts to 54 N.m (40 lbs. ft.)

19. Remove jack stand 20. Right frame to left frame retaining bolts. Refer to Frame and Underbody (Section 10-3). 21. Power steering cooler lines 22. Transaxle mounting nuts

Tighten Nuts to 50 N.m (37 lbs. ft.)

23. Left stabilizer shaft to control arm nuts 22. Stabilizer shaft bolts and reinforcement plates to frame using a jack stand for support. 25. Pinch bolt to control arms. Refer to Front Suspension (Section 3C). 26. Engine splash shields 27. Front tire and wheel assemblies. Refer to Tires and Wheels (Section 3E). 28. Lower vehicle and remove J 24867-A. 29. Steering shaft pinch bolt. Refer to Power Steering Gear and Pumps (Section 3B1). 30. Three upper transaxle bolts and ground wires to engine

Tighten Bolts to 75 N.m (55 lbs. ft.)

31. Vacuum modulator line to modulator 32. Transaxle shift cable, mounting bracket and lever 33. T.V. cable to throttle body and transaxle 34. T.C.C. switch electrical connector 35. A/C low pressure switch electrical connector 36. Neutral start switch electrical connector 37. Air cleaner and duct assembly 38. Negative battery cable

Adjust T.V. cable. Refer to "T.V. Cable Setting" in the Service Manual Toe-in, if required. Refer to Wheel Alignment (Section 3A). Transaxle fluid.

Inspect Proper fluid levels. Fluid leaks.

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.