BENDIX AD-9 Service Data page 18

AD-9 AIR DRYER TROUBLESHOOTING CHART (Continued)
SYMPTOMS
6. (Continued.)
7. “Pinging” noise
excessive during
compressor loaded
cycle.
8. Constant seepage of air
at air dryer purge valve
exhaust (non-charging
mode.)
9. The air dryer purge
piston cycles rapidly in
the compressor
unloaded
(noncompressing)
mode.
18
CAUSE
D. Compressor passing
excessive oil.
E. Desiccant cartridge not
assembled properly to
end cover. (Loose
attachment)
A. Single cylinder
compressor with high
pulse cycles.
A. Inlet of air compressor
pressurized by
turbocharger from
engine.
B. Defective check valve
assembly in AD-9 air
dryer end cover.
A. Compressor fails to
“unload”.
REMEDY
D. Check for proper compressor installation; if
symptoms persist, replace compressor.
E. Check the torque on the desiccant cartridge to
end cover attachment. Refer to assembly
section of this data sheet.
A. A slight “pinging” sound may be heard during
system build up when a single cylinder
compressor is used. If this sound is deemed
objectionable, it can be reduced substantially
by increasing the discharge line volume.
This can be accomplished by adding an
additional four feet of discharge line or adding
a 90 cubic inch reservoir between the
compressor and the AD-9 air dryer.
A. Some leakage of pressure past the metal seat
of the turbo cutoff feature of the AD-9 is to be
expected also may be audible. This slight loss
of air will not effect the engine or turbo
performance.
B. Refer to Remedy C, Symptom #1.
A. Faulty governor installation; no air line from
governor to compressor or line is “kinked” or
restricted. Install or repair air line.