18
AD-4
™
AIR DRYER TROUBLESHOOTING CHART (Continued)
SYMPTOMS
2. Water and/or Oil in
Supply or Service
Reservoir (continued).
Discharge Line Freeze-Up The discharge line must
maintain a constant slope down from the
compressor to the air dryer inlet fitting to avoid low
points where ice may form and block the flow. If,
instead, ice blockages occur at the air dryer inlet,
insulation may be added here, or if the inlet fitting is
a typical 90 degree fitting, it may be changed to a
straight or 45 degree fitting. For more information on
how to help prevent discharge line freeze-ups, see
Bendix Bulletins TCH-08-21 and TCH-08-22. Shorter
discharge line lengths or insulation may be required
in cold climates.
Insufficient coolant flow through compressor.
Inspect coolant line. Replace as necessary (I.D.
is 1/2" min.). Inspect the coolant lines for kinks
and restrictions and fittings for restrictions.
Replace as necessary. Verify coolant lines go
from engine block to compressor and back to the
water pump. Repair as necessary.
Restricted air inlet (not enough air to
compressor). Check compressor air inlet line for
restrictions, brittleness, soft or sagging hose
conditions etc. Repair as necessary. Inlet line
size is 3/4 ID. Maximum restriction requirement
for compressors is 25 inches of water. Check the
engine air filter and service if necessary (if
possible, check the air filter usage indicator).
Poorly filtered inlet air (poor air quality to
compressor). Check for leaking, damaged or
malfunctioning compressor air inlet components
(e.g. induction line, fittings, gaskets, filter bodies,
etc.). Repair inlet components as needed. Note:
Dirt ingestion will damage compressor and is not
covered under warranty.
If you found excessive oil present in the service
reservoir and you did not find any issues above,
the compressor may be passing oil.
Replace compressor. If still under warranty, follow
normal warranty process.
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 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.
CAUSE
REMEDY
G. Compressor malfunction.
F. Restricted discharge line. See Appendix A,
Table A, column 1 & 2 for recommended sizes.
If discharge line is restricted or more than 1/16"
carbon build up is found, replace the discharge
line. Replace as necessary.
F. Air compressor
discharge and/or air
dryer inlet temperature
too high.
