Symptom Tree t009
| Cause | Correction |
|---|
|
Air system leaks |
Block the vehicle wheels and check the air system for leaks with spring brakes applied and released. Check for leaks from the air compressor gaskets and the air system hoses, fittings, tanks, and valves. Refer to Procedure 012-019. |
 |
|
Unloader valve is malfunctioning |
Check the unloader valve and unloader body seal. Refer to Procedure 012-013. |
|
|
Air governor is malfunctioning or not set correctly |
Check the air governor for correct operation. Make sure the air governor is located less than 0.6 m [2 ft] from the air compressor. Refer to Procedure 012-017 or 012-018. |
|
|
Splined drive coupling or gear is excessively worn |
Check the coupling for wear. Refer to Procedure 012-014. |
|
|
Air compressor intake or exhaust valve leaks air |
Inspect the air compressor intake and exhaust valve assemblies. Refer to the Master Repair Manual, Holset® Air Compressors, Bulletin 3666121. |
|
|
Air compressor is excessively worn or internally damaged |
Replace or rebuild the air compressor. Refer to the Master Repair Manual, Holset® Air Compressors, Bulletin 3666121. |
