BOLT 8B9519 - Caterpillar

Use this procedure in order to troubleshoot an air starter motor problem.Probable Causes
Air pressure
Starting motorRecommended Actions
Table 1
Troubleshooting Test Steps Values Results
1. Check for Low Air Pressure
A. Inspect the supply lines for leaks and obstructions.
B. If a tank is used for the supply pressure, make sure that the size of the tank is sufficient.
C. Check the pressure regulator for proper adjustment.
Air Pressure
Result: The the air pressure is OK.
Proceed to Test Step 2.
Result: The the air pressure is NOT OK.
Repair: Determine the cause of the low air pressure and correct the problem.
If the problem is not resolved, proceed to Test Step 2.
2. Inspect the Air Starting Motor
A. Check the air starting motor for the following conditions:
- Worn seals
- Cracked vanes
- The height of a vane less than 32 mm (1.25 inch).
- Loose or rough bearings
- Scored rotor body
- Scored end plate
- Cracked or scored cylinder
Starting Motor
Result: The air starting motor is NOT OK.
Repair: Repair or replace the air starting motor.
Verify that the repair eliminated the problem.
If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).