Cleaning, Inspection and Testing

TOOLS REQUIRED:
J 54401 Tension Scale
J 8001 Dial Indicator
J 26900-13 Magnetic Base
J 26900-5 Vernier Caliper
J 39200 Digital Multimeter

CLEAN
^ All starter motor parts.

NOTE: Do not use grease dissolving solvents for cleaning. Such solvents will dissolve the grease packed in the overrunning clutch and may damage the armature and field coil insulation.

Cleaning Commutator:

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

MEASURE

Measuring Commutator Run-Out:

1. Place the armature onto a pair of "V-blocks." Using a J 8001 with a J 26900-13, measure commutator run-out. Standard commutator run-out is 0.05 mm (0.002 inch) or less. If run-out exceeds 0.40 mm (0.016 inch), replace the armature.

Measuring Commutator Wear:

2. Commutator wear using a J 26900-5 to measure the outside diameter of the commutator. Standard commutator outside diameter is 29.4 mm (1.157 inch). If the outside diameter is less than 28.8 mm (1.134 inch), replace the armature.

Measure Commutator Insulation Depth:

3. Commutator insulation depth. Standard commutator insulation depth is 0.5 to 0.8 mm (0.020 inch to 0.031 inch). If insulation depth is less than 0.2 mm (0.008 inch), replace the armature.

Measuring Armature Core-to-Commutator Resistance:

4. Resistance between armature core and commutator using a J 39200. If resistance is 5.0 ohms or less, the armature is grounded and must be replaced.

Measuring Commutator Resistance:

5. Resistance between commutator segments using the J 39200. If resistance is not 5.0 ohms or less at any test point, there is an open circuit in the commutator and the armature must be replaced.

Measuring Brush Length:

6. Brush length using the J 26900-5. Standard brush length is 17.5 mm (0.67 inch). If brush length is less than 12.0 mm (0.47 inch), replace the brush.

Measuring Brush Holder Resistance:

7. Resistance between positive brush holder and 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.

Measuring Brush Spring Tension:

8. Brush spring tension using a J 54401. Standard tension is 1.9 kg (4.19 lbs.). If brush spring tension is less than 0.7 kg (1.54 lbs.), the brush spring must be replaced.

Measuring Starter Solenoid Pull-In Coil Resistance:

9. Starter solenoid pull-in coil resistance between terminal "S" and terminal "M" using the J 39200. If resistance is not 5.0 ohms or less, the pull-in coil is open and the starter solenoid must be replaced.

Measuring Starter Solenoid Hold-In Coil Resistance:

10. Starter solenoid hold-in coil resistance between terminal "S" and the solenoid case using the J 39200. If resistance is not 5.0 ohms or less, the hold-in coil is open and the starter solenoid must be replaced.

INSPECT
1. Pinion drive lever for wear; replace as necessary.

Inspecting Overrunning Clutch Operation:

2. Overrunning clutch for wear, damage or other abnormal conditions. Check that the clutch locks when turned in the drive direction and rotates smoothly in the reverse direction. Replace as necessary.

Inspecting Overrunning Clutch Spline Teeth:

3. Overrunning clutch spline teeth for wear or damage; replace as necessary.

Inspecting Armature Brushing And Bearing:

4. Armature bushing and bearing for wear and damage; replace as necessary.

Inspecting Starter Solenoid Plunger Operation:

5. Starter solenoid plunger by pressing the plunger in and releasing it. If the plunger does not return to its original position quickly, the starter solenoid must be replaced.

Inspecting Internal Gear Assembly And Idle Gears:

6. Internal gear assembly and idle gears for wear, damage or other abnormal conditions; replace as necessary.
7. Check the brush springs for corrosion or damage. Also check the brush holder and the insulation on the positive plates for wear. Replace components as needed.