1. Remove the starter motor from the vehicle. Refer to Starter Motor Replacement .



2. Scribe matchmarks (2) on the solenoid and the drive housing to ensure proper solenoid installation.



3. Remove the retaining nut and the field coil lead wire (2) from the solenoid.



4. Remove the 2 screws and the solenoid (1) from the drive housing.




Important: Do not disassemble the starter solenoid. If it is found to be defective, replace the solenoid.

5. Inspect the plunger (3) and spring for wear. Replace as necessary.



6. Remove two bolts, two screws and the commutator end housing (1) from the drive housing.
7. Remove the commutator end bushing and the washers.



8. Remove the brush holder (1) and brushes (4) from the commutator end of the armature.




Notice: If the armature bearing comes out during removal, apply grease to it and reinsert it.

9. Remove the armature (1) and the starter motor yoke (2) from the drive housing.



10. Remove the idle gear retainer (2) and the idle gears (3) from the gear shaft assembly (4).



11. Remove the pinion drive lever seal (3) and the plate (4) from the drive housing (1).



12. Remove the motor gear shaft (2) assembly with the pinion drive lever (4) from the drive housing (1).



13. Remove the overrunning clutch retaining ring (2), the stop ring (4) and the overrunning clutch (1) from the motor gear shaft (3).

Tools Required

Notice: Do not use grease dissolving solvents for cleaning the overrunning clutch or armature. Solvents dissolve the grease packed in the clutch and damage the armature and the field coil insulation.

1. Clean all starter motor parts.



2. Remove dirt and burn marks from the commutator end (2) of the armature (1) by sanding with a #300 or #400 grit sandpaper. Wipe the parts with a clean shop cloth.



3. Place the armature onto a pair of V-blocks (1). Measure the commutator run-out using a J 8001 with a J 26900-13 . If the run-out exceeds the maximum, replace the armature.

Standard Commutator Run-out
0.05 mm (0.002 in) or less

Maximum Commutator Run-out
0.40 mm (0.016 in)




4. Measure the outside diameter of the commutator using a J 26900-5 . If the outside diameter is less than the minimum, replace the armature (1).

Standard Commutator Diameter
29.4 mm (1.157 in)

Minimum Commutator Diameter
28.8 mm (1.134 in)




5. Measure the commutator insulation (1) depth. If the insulation depth is less than the minimum, replace the armature.

Standard Commutator Insulation Depth
0.5 to 0.8 mm (0.020- 0.031 in)

Minimum Commutator Insulation Depth
0.2 mm (0.008 in)




6. Measure the resistance between the armature core (1) and the commutator (2) using a J 39200 . If the resistance is 5.0 ohms or less, the armature is grounded and must be replaced.



7. Measure the resistance between the commutator segments using J 39200 . If resistance is greater than 5.0 ohms at any test point, there is an open circuit in the commutator and the armature must be replaced.



8. Measure the resistance between the positive brush holder and the negative brush holder using the J 39200 . If the resistance is 5.0 ohms or less, the brush holder is grounded and must be replaced.



9. Measure the brush (1) length using the J 26900-5 . If the brush length is less than the minimum, replace the brush.

Standard Brush Length
17.5 mm (0.67 in)

Minimum Brush Length
12.0 mm (0.47 in)

10. Inspect the brush springs for corrosion or damage. Also inspect the brush holder and the insulation on the positive plates for wear. Replace components as necessary.



11. Measure the brush spring (2) tension using a J 544-01 . If the brush spring tension is less than the minimum, replace the brush spring.

Standard Brush Spring Tension
1.9 kg (4.19 lbs)

Minimum Brush Spring Tension
0.7 kg (1.54 lbs)




12. Measure the starter solenoid pull-in coil resistance between terminal S (3) and terminal M using the J 39200 . If the resistance is greater than 5.0 ohms the pull-in coil is open and the starter solenoid must be replaced.



13. Measure the starter solenoid hold-in coil resistance between terminal S (3) and the solenoid case using the J 39200 . If the resistance is greater than 5.0  ohms, the hold-in coil is open and the starter solenoid must be replaced.



14. Inspect the pinion drive lever (4) for wear. Replace as necessary.



15. Inspect the overrunning clutch (1) for wear, damage or other abnormal conditions. Verify that the clutch locks when turned in the drive direction and rotates smoothly in the reverse direction. Replace as necessary.



16. Inspect the overrunning clutch spline teeth (1) for wear or damage. Replace as necessary.



17. Inspect the armature bushing and bearing (1) for wear and damage. Replace as necessary.
18. Inspect the commutator end bushing for wear and damage. Replace as necessary.



19. Inspect the starter solenoid plunger by pressing the plunger in and releasing it. If the plunger does not return to its original position quickly, replace the starter solenoid (1).



20. Inspect the internal gear assembly (1) and the idle gears (2,3) for wear, damage or other abnormal conditions. Replace as necessary.

1. Lightly grease the gear shaft with Lubriplate lubricant GM P/N 1050109, or the equivalent.



2. Install the overrunning clutch assembly and the overrunning clutch stop ring to the gear shaft assembly.
3. Install the overrunning clutch retaining ring to the gear shaft assembly. Slide the overrunning clutch stop ring (4) away from the overrunning clutch assembly to cover the overrunning clutch retaining ring (2).
4. Lightly grease the pinion drive lever contact points with Lubriplate lubricant GM P/N 1050109, or the equivalent.



5. Install the gear shaft assembly with the pinion drive lever (4) to the drive housing (1).



6. Install the pinion drive lever seal (3) and the plate (4) to the drive housing (1).
7. Lightly grease the idle gears with Lubriplate lubricant GM P/N 1050109, or the equivalent.




Important: Align the notches in the idle gear retainer with the bolt holes in the drive housing.

8. Install the 3 idle gears (3) to the drive housing (1). Secure with the idle gear retainer (2).



9. Lightly grease the armature bearing with Lubriplate lubricant GM P/N 1050109, or the equivalent.
10. Install the armature bearing (2) to the gear shaft.



11. Install the armature (1) to the field frame (2).
12. Install the armature bushing to the armature.



13. Align the matchmarks and install the field frame (3) to the drive housing.



14. Install the brushholder assembly (1) to the commutator end.




Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

15. Install the spring washer (2) and the commutator end cover; secure with 2 bolts and 2 screws.

Tighten
Tighten the commutator end housing bolts to 30 N·m (22 lb in).

16. Lightly grease the solenoid plunger with Lubriplate lubricant GM P/N 1050109, or the equivalent.



17. Install the solenoid plunger (3) and spring.



18. Install the solenoid to the drive housing, aligning the matchmarks (2).



19. Install the 2 solenoid mounting screws.

Tighten
Tighten the solenoid (1) mounting screws to 7 N·m (62 lb in).




20. Install the field coil lead wire (2) and the retaining nut to the solenoid.

Tighten
Tighten the field coil lead wire retaining nut to 15 N·m (11 lb in).

21. Install the starter to the vehicle. Refer to Starter Motor Replacement .