Bendix Commercial Vehicle Systems AD-SP SYSTEM PURGE AIR DRYER 10/04 - Manual (Page 23)

23
BENDIX ® AD-IP ® AIR DRYER TROUBLESHOOTING CHART
SYMPTOMS CAUSE REMEDY
2. Water and/or oil in
the supply or service
reservoir (continued).
G. Compressor malfunction. G. If you found excessive oil present in the service
reservoir and you did not find any issues above,
the compressor may be passing oil. Test the
compressor using the Bendix ® BASIC ™ cup method
as described in the Bendix compressor service
manual and referred to in Appendix A, Table A,
column 5.
Replace compressor. If still under warranty, follow
normal warranty process.
H. Air by-passes desiccant
cartridge assembly.
H. If the vehicle uses a Holset ® compressor, inspect
the feedback check valve for proper installation and
operation. When replacing the desiccant cartridge,
make sure the desiccant cartridge assembly is
properly installed and the sealing rings are in place
on the mounting surface of the desiccant cartridge.
I. Desiccant requires
replacement.
I. Replace the desiccant cartridge assembly.
Refer to Appendix A, Table A columns 3 & 4 for
recommended intervals.
3. Oil present at the air
dryer purge exhaust
or cartridge during
maintenance.
A. Air brake charging system is
functioning normally.
A. Air dryers remove water and oil from the air brake
charging system. A small amount of oil is normal.
Check that the regular maintenance is being
performed and that the amount of oil in the air tanks
(reservoirs) is within the acceptable range shown on
the BASIC cup (see also column 5 of Appendix A,
Table A). Replace the air dryer cartridge as needed
and return the vehicle to service.
B. The Bendix ® AD-IP ® PuraGuard ® oil coalescing air
dryer removes more oil from the brake system than
the standard Bendix ® AD-IP ® air dryer.
4. Safety valve on the air
dryer “popping off” or
exhausting air.
A. Restriction between air dryer
and supply (first) reservoir.
A. Check to determine if air is reaching the supply
reservoir. Inspect for kinked tubing or hose. Check
for undrilled or restricted hose or tubing fittings and
repair or replace as needed.
B. Air dryer safety valve
malfunction.
B. Verify the relief pressure is at the vehicle or
component manufacturer specifications. Replace
if malfunctioning.
C. Desiccant cartridge
maintenance required.
C. Refer to Table A and column 3. Check the
compressor for excessive oil passing and/or correct
compressor installation. Repair or replace as
necessary. Replace the desiccant cartridge.
D. Malfunctioning discharge
check valve in the end cover
of the AD-IP air dryer.
D. Test to determine if air is passing through the check
valve. Repair or replace.
E. Excessive pressure
pulsations from the
compressor. (Typical single
cylinder type.).
E. Increase the volume in the discharge line by
increasing the length or diameter. Add a ping tank
(small reservoir).
F. Governor malfunction.
Missing or restricted
governor control line
installation.
F. Test the governor operation and/or inspect the
control line leading from the governor UNL
(unloader) port to the air dryer control port.