Check Valve

CAUSE

REMEDY

2. Water and/or Oil in Supply

(Continued)

Poorly ﬁltered inlet air (poor air quality to compressor). Check

o r S e r v i c e R e s e r v o i r

for leaking, damaged or malfunctioning compressor air inlet

(continued).

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.

H. Compressor malfunction.

H. If excessive oil is present in the service reservoir and no other

issues (from above) were found, 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.

I. Air by-passes desiccant cartridge

I. If the vehicle uses a Holset® compressor, inspect the

assembly.

feedback check valve for proper installation and operation.

When replacing the desiccant cartridge, make sure desiccant

cartridge assembly is properly installed and sealing rings are in

place on mounting surface of desiccant cartridge.

			Feed Back Line
			Typical Drop-In Air Dryer End Cover

	J.	Desiccant requires replacement.	J. Replace desiccant cartridge assembly. Refer to Appendix A,
			Table A columns 3 & 4 for recommended intervals.
3. Oil present at air dryer purge A.		Air brake charging system is	A. Air dryers remove water and oil from the air brake charging
exhaust or cartridge during		functioning normally.	system. A small amount of oil is normal. Check that regular
maintenance.			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.