Bendix Commercial Vehicle Systems TROUBLE SHOOTING COMPRESSOR - Manual (Page 13)

13
Symptom: What it may indicate: What you should do:
This guide attempts to cover most
compressor system problems. Here
are some rare sources of problems not
covered in this guide:
• Turbocharger leakage. Lubricating
oil from leaking turbocharger seals can
enter the air compressor intake and give
misleading symptoms.
• Where a compressor does not have
a safety valve installed, if a partial or
complete discharge line blockage has
occurred, damage can occur to the
connecting rod bearings. Damage of this
kind may not be detected and could lead
to compressor problems at a later date.
17.0 Compressor
leaks coolant
(a) Improperly installed plugs or
coolant line fittings.
(b) Damaged compressor head
gasket.
(c) Porous compressor head casting.
 Inspect for loose or over-torqued fittings.
Reseal and tighten loose fittings and plugs
as necessary. If over-torqued fittings and
plugs have cracked ports in the head,
replace the compressor.
 An air leak at the head gasket may indicate
a downstream restriction such as a freeze-
up or carbon blockage and/or could indicate
a defective, or missing, safety valve. Find
blockage (go to 9.0(f) for details) and then
replace the compressor. Do not re-use the
safety valve without testing. See Symptom
12.0(a).
 If casting porosity is detected, replace the
compressor.
18.0 Noisy
compressor
(multi-cylinder
compressors only)
(a) Damaged compressor.  Replace the compressor.
Testing for leaks with
soap solution.
16.0 Compressor
leaks air
(a) C o m p r e s s o r l e a k s a i r a t
connections or ports.
(b) Compressor unloader mechanism
malfunction.
(c) Damaged compressor head
gasket.
 Check for leaking, damaged or defective
compressor fittings, gaskets, etc. Repair
or replace as necessary.
 Go to Test 6 on page 15.
 An air leak at the head gasket may indicate
a downstream restriction such as a freeze-
up or carbon blockage and/or could indicate
a defective or missing safety valve. Find
blockage (go to 9.0(f) for details) and then
replace the compressor. Do not re-use the
safety valve without testing. See Symptom
12.0(a).
Other Miscellaneous Areas to Consider

Head
gasket
location