GM Metro/Sprint 1985-1993 Repair Guide




See Figure 1

The terms flywheel and flexplate are used interchangeably. They describe the gear toothed ring attached to the crankshaft that the starter uses to turn the engine over. The automatic transaxle flywheel is sometimes referred to as a flexplate.

On manual transaxle equipped vehicles, the flywheel is the mounting point and friction surface for the clutch disc and pressure plate. On automatic transaxle equipped vehicles, the flywheel is the attaching point for the torque converter.

The flywheel and ring gear are machined from one piece of metal and cannot be separated. If gear teeth are damaged, the flywheel must be replaced as an assembly.

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Fig. Fig. 1: Measuring flywheel runout - manual transaxle shown

  1. Disconnect the negative battery cable. Raise and support the vehicle safely.
  3. Remove the transaxle from the vehicle.
  5. On manual transaxle equipped vehicles, inspect the flywheel/pressure plate assembly for match marks. If no mark exists, mark the flywheel and the pressure plate for installation reference.

The flywheel is balanced and must be replaced in the same position to ensure trouble free operation of the engine.

  1. On manual transaxle equipped vehicles, loosen the clutch-to-flywheel bolts, evenly (one turn at a time), until the spring tension is relieved, then remove the retaining bolts, the pressure plate and the clutch assembly.

The clutch driven disc contains asbestos, which has been determined to be a cancer causing agent. Never clean clutch surfaces with compressed air! Avoid inhaling any dust from any clutch surface! When cleaning clutch surfaces, use a commercially available brake cleaning fluid.

  1. Check the flywheel face for runout using a dial indicator. If runout exceeds 0.0078 in. (0.2mm), resurface the flywheel prior to installation.
  3. Remove the flywheel-to-crankshaft bolts and the flywheel from the engine.

To install:
  1. On manual transaxle equipped vehicles, clean the clutch disc (use a stiff brush), the pressure plate and the flywheel of all dirt, oil and grease.
  3. Inspect the flywheel, the pressure plate and the clutch disc for scoring, cracks, heat checking and/or other defects.
  5. If flywheel resurfacing is needed sent the flywheel to an experienced machine shop.

When the flywheel is removed, it is a good idea to replace the rear main oil seal, the pilot bushing and/or the clutch plate (as necessary).

  1. Install the flywheel on the crankshaft and align the matchmarks.
  3. Apply Loctite® sealant, or equivalent, to the flywheel retaining bolt threads.
  5. Install the flywheel retaining bolts and tighten to 41-47 ft. lbs.. (56-64 Nm).
  7. On manual transaxle equipped vehicles, position a clutch disc aligner tool in the pilot bushing (to support the clutch disc), then assemble the clutch disc (the damper springs facing the transaxle) and pressure plate. Align the matchmarks made during removal and install the retaining bolts into the flywheel.
  9. Tighten the pressure plate-to-flywheel bolts to 17 ft. lbs.. (23 Nm) gradually and evenly (to prevent clutch plate distortion). Then remove the alignment tool.
  11. On manual transaxle equipped vehicles, lubricate the pilot bushing and the clutch release lever.
  13. Install the transaxle, lower the vehicle and connect the negative battery cable.
  15. On manual transaxle equipped vehicles, adjust the clutch linkage.