T M 5 - 3 8 0 5 - 2 6 2 - 2 0
3-19. AIR BRAKE SYSTEM TROUBLESHOOTING (CONT)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
3. LOW AIR PRESSURE (AIR PRESS GAGE INDICATES IN RED ZONE AND LOW AIR PRESSURE
BUZZER SOUNDS) (Cont).
Step 16.
4. AIR PRESSURE
Step 1.
Step 2.
(Cont).
a. If bubbles seen, replace treadle and valve (page 7-53).
b. If bubbles not seen, replace
BUILDS UP SLOWLY.
Remove engine right side panels
Check air compressor drive belt
a. If air compressor drive belt
(page 7-97).
b. If air compressor drive belt
below.
pilot valve (page 7-74).
(page 9-14).
adjustment (page 7-97).
is not adjusted properly, adjust
is adjusted properly, go to step 2
Open drain valve located at bottom of air compressor and drain air.
Disconnect hose shown below and install 3/8 NPT pipe cap on adapter
to which hose was connected. Close drain valve.
Start engine and operate at 1000 rpm. See if air pressure builds up
a n y f a s t e r.
a .
b .
If air pressure builds up faster, shut off engine and go to
MALFUNCTION 3, step 10 (page 3-125).
If air pressure still builds up slowly, shut off engine, open
air reservoir drain valve, remove 3/8 NPT pipe cap, reconnect
hose, close drain valve, and go to step 3 below.
3-128
