BRAKES TROUBLESHOOTING AND MAINTENANCE PROCEDURES.
TEST OR INSPECTION
EXCESSIVE BUILD-UP AND RECOVERY TIME.
Compressor should build up air system from 85-100 psi in 40 seconds with engine at maximum rpm.
Step 1. Check for dirty engine air filters.
If dirty--replace air filters. Refer to TM 5-3805-261-20.
Step 2. Check for restricted air inlet line.
Remove restriction or replace air inlet line if kinked. Refer to TM 5-3805-261-20.
Step 3. Check for carbon build-up or restrictions in compressor discharge line and discharge port.
If carbon build-up is found, check for proper compressor cooling. Replace discharge line if damaged.
Refer to TM 5-3805-261-20.
Step 4. Check for sticking unloader pistons and plungers. Plungers and pistons should be fully retracted when in
inlet cavity and compressor is loaded (pumping air).
If pistons and plungers are not retracted, check operation of air compressor governor. If governor is
working properlyreplace pistons and plungers. Refer to paragraph 6-13. Repair or replace compressor
after completing steps 1 thru 4, if necessary.
COMPRESSOR FAILS TO UNLOAD.
Step 1. Check installation and operation of governor.
If governor does not operate properly--repair. Refer to paragraph 6-14.
Step 2. Check for defective or worn unloader pistons and bores.
If pistons and bores are dirty, corroded or worn--replace. Refer to paragraph 6-13. Repair or replace
compressor after checking steps 1 and 2, if necessary.