TM 5-3810-307-24-1-1
Direct/General Support Troubleshooting - Continued
SYMPTOM
PROBABLE CAUSE
CORRECTIVE ACTION
AIR SYSTEM
1. Air dryer is constantly
a. Defective check valve
a. Remove check valve. Apply air
cycling or purging.
assembly in air dryer end
pressure to delivery side of
cover.
valve. Apply soap solution at
opposite end and check for
leakage (1" bubble in 5 seconds
permissible). If excessive
leakage is present, replace the
check valve assembly.
b. Defective governor.
b. Test governor for proper cut-in
and cut-out pressures and
excessive leakage in both
positions. Replace governor if
defective.
c. Leaking purge valve housing
c. With supply port open to
assembly and/or o-rings in
atmosphere, apply 120 psi air
air dryer end cover.
pressure at the control port.
Apply a soap solution to the
supply port and exhaust port
(purge valve seat area).
Permissible leakage - 1" bubble
in 5 seconds. Replace
defective components.
d. Compressor unloader
d. Remove air strainer or fitting
mechanism leaking
from compressor inlet cavity.
excessively.
with compressor unloaded,
check for unloader piston
leakage. Slight leakage is
permissible. Repair or replace
compressor if leakage is
excessive.
e. Rapid cycling of the
e. Check for kinks or restrictions in
governor due to air
line connected to RES port.
starvation at the RES port of
Replace damaged line as
governor.
necessary.
2. Excessive water in
a. Air dryer desiccant requires
a. Replace desiccant cartridge.
system.
replacement.
b. Air dryer purge valve stuck
b. Test operation of valve.
closed.
Replace defective valve.
c. Air bypassing desiccant
c. Check cartridge for proper
cartridge.
installation. Replace o-ring for
cartridge end cover.
1-5-16
