Inspection and Measuring Procedure

NOTE: 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 J26900-5. 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 (.035 in) replace the contact plate.