32
A-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 overtorqued 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) Compressor leaks air at connections
or ports.
(b) Compressor unloader mechanism
malfunction.
(c) Damaged compressor head
gasket(s).
Check for leaking, damaged or defective
compressor fittings, gaskets, etc. Repair
or replace as necessary.
Go to Test 6 on page A-15.
An air leak at the head gasket(s) 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
reuse the safety valve without testing. See
Symptom 12.0(a).
Other Miscellaneous Areas to Consider
Head
gasket
locations
