Starting Motor - Delco 50-MT Caterpillar

The possible causes of this failure are listed below:

• The solenoid return spring is weak.

• The solenoid return spring is broken.

• The shift lever assembly is binding.

• The shift lever assembly is broken.

• The solenoid of the starting motor is faulty.

Test Step 1. INSPECT THE SOLENOID RETURN SPRING

1. Remove the starting motor.

2. Disassemble the starting motor. See Disassembly and Assembly.

3. Visually inspect the solenoid return spring.

Expected Result:

The return spring is not weak. The return spring is not broken.

Results:

• OK - The return spring is not weak and the return spring is not broken. Proceed to test step 2.

• NOT OK - The return spring is weak or the return spring is broken.

  Repair: Replace the solenoid return spring.

  STOP

Test Step 2. INSPECT SHIFT LEVER ASSEMBLY

1. Visually inspect the shift lever assembly.

Expected Result:

The shift lever assembly is not binding. The shift lever assembly is not broken.

Results:

• OK - The shift lever assembly is not binding and the return spring is not broken.

  Repair: The starting motor solenoid is incorrect. Replace the solenoid.

  STOP

• NOT OK - The shift lever assembly is binding or the shift lever assembly is broken.

  Repair: If the shift lever assembly is binding, thoroughly clean the shift lever and thoroughly clean the armature shaft. If the shift lever assembly is broken, replace the shift lever assembly.

  STOP