Tools Required

Caution: Keep fingers and tools away from the opening in the starter drive housing while performing the Starter No Load Test. The strong shifting action of the solenoid could cause personal injury or damage as the drive pinion moves into the cranking position and spins.

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



2. Connect test leads from the battery and the ammeter to the starter motor. The pinion should extend quickly and completely and the starter motor should run smoothly.
3. Measure the starter motor current draw. The starter motor current draw at 11 volts is 90 amperes. Refer to Starter Motor Usage .

Rated current draw and no-load speed indicate the normal condition of the starter motor.

Low free speed and high current draw indicate the following conditions:

Failure to operate and high current draw indicates the following conditions:

Failure to operate and low or no current draw indicates the following conditions:

Low no-load speed and low current draw indicates the following conditions:

High free speed and high current draw indicate shorted fields. If the fields are shorted, replace the field coil assembly. Use a growler in order to inspect for a shorted armature.

If any of the above conditions are unsatisfactory, refer to Starter Motor Overhaul .

Notice: Do not allow the solenoid pull-in current to flow for more than 15 seconds at a time. The windings can be damaged by overheating. Also, the current draw readings will decrease as the windings heat up.




1. Remove the field coil lead wire from the solenoid terminal C (1).
2. Install the test leads from the battery to the starter motor.
3. Ensure that the pinion extends quickly and completely to the energized position (pull-in test).



4. Remove the negative lead from the solenoid terminal C (1).
5. Verify that the pinion remains completely in the energized position (hold-in test).



6. Remove the negative lead from the drive housing.
7. Ensure that the pinion returns quickly and completely to the de-energized position (pinion return test).
8. If the pinion does not return to the de-energized position, the cause is most likely a faulty starter solenoid return spring. Replace the starter solenoid.
9. If any of the above tests are not satisfactory, replace the starter solenoid.

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.

10. Install the field coil lead wire to the solenoid terminal.

Tighten
Tighten the nut to 6 N·m (52 lb in).

11. Install the starter motor to the vehicle. Refer to Starter Motor Replacement .

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



2. Remove the nut and the solenoid wire (1) from the solenoid assembly.



3. Remove the two through bolts (1) and separate the field frame (with armature) from the solenoid assembly.



4. Remove the three bolts (1) and the solenoid end cover (2).



5. Inspect the starter solenoid plunger by pressing the plunger into the starter solenoid (1) and releasing the plunger. If the plunger does not return to its original position quickly, replace the starter solenoid.
6. Remove the solenoid plunger.



7. Remove the two bolts (2) and separate the drive housing (1) from the solenoid assembly.



8. Inspect the overrunning clutch (1) for wear, damage and other abnormal conditions.

Verify that the following conditions exist:

•	The clutch locks when it is turned in the drive direction.

•	The clutch rotates smoothly in the reverse direction.

•	Replace the clutch assembly as necessary.

9. Inspect the overrunning clutch spline teeth (2) for wear and damage. Replace the clutch assembly as necessary.



10. Remove the idler gear (5) from the drive housing.
11. Carefully remove the idler gear roller bearing (1) from the drive housing. The needle bearings may fall out during disassembly.
12. Remove the return spring (3) from the drive housing.
13. Remove the clutch and drive assembly (4) from the drive housing by gently tapping on the pinion end with a rawhide mallet.
14. Inspect the drive housing assembly components for wear, damage or other abnormalities.
15. Replace the components as necessary.
16. Inspect the clutch and drive assembly bearings for wear, damage and smooth operation.
17. Replace the bearings as necessary.



18. Inspect the armature bearings (1) for smooth operation, wear and damage.
19. Replace the bearings as necessary.



20. Remove the steel ball (2) from the clutch and drive assembly.



21. Remove the following components from the field frame:

•	The two screws (3)

•	The end cover (2)

•	The O-ring (discard)




22. Remove the brushes.
23. Hold the spring back with a small screwdriver (2) and remove the brush (4) from the brush holder.
24. Disconnect the four brushes.
25. Remove the brush holder.
26. Remove the armature from the field frame.
27. Inspect the brush springs for corrosion and damage. Replace the components as necessary.
28. Inspect the brush holder and the insulation on the positive plates for wear and damage. Replace the components as necessary.



29. Remove the following from terminal 30 of the solenoid assembly:

•	The nut (1)

•	The wave washer (2)

•	The outside insulator (4)

•	The O-ring (5)

•	The bolt (11)

•	The contact plate (10)

•	The inside insulator (8)

•	The insulation paper (6)




30. Remove the following from terminal C of the solenoid assembly:

•	The nut (9)

•	The wave washer (8)

•	The outside insulator (7)

•	The O-ring (6)

•	The bolt (1)

•	The contact plate (2)

•	The inside insulator (3)

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 of the starter motor parts.



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



3. Place the armature onto a pair of V-blocks (1).
4. Measure the commutator runout using the J 8001 with the J 26900-13 . Replace the armature if the runout exceeds the standard.

Standard Commutator Runout
0.05 mm (0.002 in)




5. Measure the commutator wear using the J 26900-5 . Replace the armature (1) if the diameter is less than the minimum.

Standard Commutator Diameter
30 mm (1.18 in)

Minimum Commutator Diameter
29 mm (1.14 in)




6. Measure the commutator insulation depth. Replace the armature if the insulation depth is less than the minimum.

Standard Commutator Insulation Depth
0.6 mm (0.024 in)

Minimum Commutator Insulation Depth
0.2 mm (0.008 in)




7. Measure the resistance between the armature core and the commutator using the J 39200 . If the resistance is 5.0 ohms or less, the armature is grounded. Replace the armature.



8. Measure the resistance between the commutator segments using the J 39200 . If the resistance is not 5.0 ohms or less at any test point, there is an open circuit in the commutator. Replace the armature.



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

Standard Brush Length
15.5 mm (0.610 in)

Minimum Brush Length
10.0 mm (0.394 in)




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

Standard Brush Length
15.5 mm (0.610 in)

Minimum Brush Length
10.0 mm (0.394 in)




11. 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. Replace the brush holder (1).



12. Measure the resistance between the lead wire (2) and the field coil brush lead (1) using the J 39200 . If the resistance is greater than 5.0 ohms replace the field frame.



13. Measure the resistance between the field coil brush lead (1) and the field frame (2) using the J 39200 . If the resistance is less than 5.0 ohms replace the field frame.



14. Measure the brush spring (2) tension using the J 544-01 . Take the reading as soon as the brush spring separates from the brush. If the tension is less than the minimum, replace the brush spring.

Standard Brush Spring Tension
1.8-2.4 kg (4.0-5.3 lb)

Minimum Brush Spring Tension
1.2 kg (2.6 lb)




15. Measure the starter solenoid pull in coil resistance between terminals 50 (3) and C (2) using the J 39200 . If the resistance is not 5 ohms or less, the pull-in coil is open. Replace the starter solenoid.



16. Measure the starter solenoid hold-in coil resistance between terminal 50 (2) and the solenoid case using the J 39200 . If the resistance is not 5.0 ohms or less, the hold-in coil is open. Replace the starter solenoid.



17. Measure the contact plate wear using the J 26900-5 . If the depth of wear is greater than 0.9 mm (0.035 in) replace the contact plate.

1. Install the following to terminal 30:

•	The insulation paper (6)

•	The inside insulator (8); long side (7), short side (9)

•	The contact plate (10)

•	The terminal bolt (11)

•	The O-ring (5)

•	The packing and outside insulator (4)

•	The wave washer (2)

Important: Do not tighten the nut (1) at this time.

•	The nut (1)




2. Install the following to terminal C:

•	The inside insulator (3); long side (4), short side (5)

•	The contact plate (2)

•	The terminal bolt (1)

•	The O-ring (6)

•	The outside insulator (7)

•	The wave washer (8)

Important: Do not tighten the nut (9) at this time.

•	The terminal nut (9)





Important: If the contact plate is not pressed down evenly, the contact plate may tilt due to the tightening of the nut. If the nut is over tightened, it may cause cracks on the inside of the insulator.

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.

3. Place a wooden block on the contact plates and press it down with a hand press. Use only enough force to hold the contact plates firmly seated in the solenoid assembly. Tighten the nuts.

Dimensions of the wooden block are 20x37x40 mm (0.79x1.46x1.57 in).

Tighten
Tighten the nuts to 17 N·m (12 lb ft).




4. Clean the contact surfaces of the contact plates (2) and the plunger (1) with a clean dry cloth.
5. Install the solenoid plunger.
6. Install the solenoid end cover.

Tighten
Tighten the nuts to 2.5 N·m (23 lb in).

7. Apply a light coating of Lubriplate lubricant GM P/N 1050109, or an equivalent, to the following locations:

•	The front armature bearing

•	The rear armature bearing

•	The idler gear roller bearing




8. Install the armature into the field frame.
9. Install the brush holder.
10. Connect the four brushes.
11. Hold the spring back with a small screwdriver (2) and install the brush (4) into the brush holder.



12. Install the end cover (2) to the field frame.

•	Install a new O-ring

•	Install the two screws (3)

Tighten
Tighten the screws to 1.5 N·m (13 lb in).




13. Install the steel ball (2) to the clutch and drive assembly.



14. Install the following to the drive housing:

•	The idler gear roller bearing (1)

•	The idler gear (5)

•	The clutch and drive assembly (4)

•	The return spring (3)




15. Install the drive housing (1) to the solenoid assembly

Tighten
Tighten the two bolts to 6 N·m (52 lb in).




16. Install the field frame to the solenoid assembly using a new O-ring.

Tighten
Tighten the two through bolts (1) to 6 N·m (52 lb in).




17. Install the solenoid lead wire and nut (1) to the solenoid assembly.

Tighten
Tighten the nut (1) to 6 N·m (52 lb in).

18. Install the starter motor to the vehicle. Refer to Starter Motor Replacement .