GM Service Manual Online
For 1990-2009 cars only

The pinion clearance should be checked after reassembly of the starter motor. The pinion clearance cannot be adjusted. Improper clearance is an indication of worn parts. In order to check the pinion clearance, perform the following procedure:

  1. Disconnect the starter motor field connector from the solenoid "M" terminal.
  2. Insulate the starter motor field connector carefully.

  3. Object Number: 1038  Size: SH
  4. Connect a 12 V battery from the solenoid switch terminal to the solenoid frame.
  5. Momentarily flash a jumper lead from the solenoid motor terminal to the solenoid frame. This will shift the pinion into the cranking position. The pinion will remain in the cranking position until the battery is disconnected.
  6. Push the pinion back toward the commutator end to eliminate thrust movement.

  7. Object Number: 1039  Size: SH
  8. Measure the distance between the pinion and the pinion stop collar.
  9. The clearance should be from 0.25-4.06 mm (0.010-0.160 in.).