Bendix Commercial Vehicle Systems BENDIX 720CC COMPRESSOR - Manual (Page 21)

A-7
Symptom: What it may indicate: What you should do:
(e) Air compressor discharge and/or
air dryer inlet temperature too
high.
(f) Insufficient coolant flow.
(g) Restricted discharge line.
 Check temperature as outlined in Test 3 on
page A-14. If temperatures are normal go
to 4.0(h).
 Inspect coolant line. Replace as necessary.
Inside Diameter (I.D.) is 1/2".
 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.
 If discharge line is restricted or more than
1/16" carbon build-up is found, replace the
discharge line. See Table A, column 2, on
page A-3 for recommended size. Replace
as necessary.
 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-008-021
and TCH-008-022 (Appendix B). Shorter
discharge line lengths or insulation may be
required in cold climates.
Temperature
Other
 Check compressor air inlet line for restric-
tions, 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).
(h) Restricted air inlet (not enough air
to compressor).
(g)
4.0 Oil in Supply
or Service
Reservoir*
(air dryer installed)
(continued)
Kinked discharge line shown.
Partly
collapsed
inlet line
shown.
Testing the temperature
at the discharge fitting.
Inspecting the coolant hoses.
*If a maintained Bendix ® PuraGuard ® system filter or Bendix ® PuraGuard ® QC oil coalescing
filter is installed, call 1-800-AIR-BRAKE (1-800-247-2725, option 2) and speak to a Tech Team
member.
(g)
(e) (f)
(h)