Pinion Does Not Engage Ring Gear While Armature Turns
System Operation Description:
The possible causes of this failure are listed below:
- The flywheel ring gear is damaged.
- The shift lever is damaged.
- The pinion drive is damaged.
Test Step 1. CHECK THE FLYWHEEL RING GEAR
- Remove the starting motor.
- Visually inspect the flywheel ring gear.
Expected Result:
The ring gear should be in good condition. The ring gear teeth should not be worn.
Results:
- OK - The flywheel ring gear is correct. Go to test step 2.
- NOT OK - The flywheel ring gear is incorrect.
Repair: Repair the ring gear or replace the ring gear.
Stop.
Test Step 2. TEST THE INTERNAL COMPONENTS OF THE STARTING MOTOR
- Disassemble the starting motor. See Disassembly and Assembly.
- Thoroughly clean the following items:
- Starting motor case
- Shift lever assembly
- Armature shaft
- Starting motor case
- Visually inspect the shift lever for damage.
Expected Result:
The shift lever is correct.
Results:
- OK - The shift lever is correct. Proceed to test step 3.
- NOT OK - The shift lever is incorrect.
Repair: Repair the shift lever or replace the shift lever.
Stop.
Test Step 3. TEST THE OPERATION OF THE PINION
- Apply ground to the starter by attaching a ground cable to the case of the starter.
- Connect +Battery to the "Bat" terminal.
- Place the starter on the bench. Apply the correct system voltage to the "S" terminal of the starter.
Expected Result:
The armature turns and the pinion gear extends properly.
Results:
- YES - The operation of the starter is correct.
Repair: Replace the starter on the machine and test for proper operation.
Stop.
- NO - The operation of the starter is not correct.
Repair: Replace the pinion drive assembly.
Stop.
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