Ad-4, Air dryer troubleshooting chart (continued) – Bendix Commercial Vehicle Systems AD-4 AIR DRYER 10/04 User Manual
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AD-4
™
AIR DRYER TROUBLESHOOTING CHART (Continued)
SYMPTOMS
CAUSE
REMEDY
6. With gauge installed at RES port of governor,
pressure should not drop below ”Cut-In” pressure
at the onset of the compressor “Unloaded”
cycle. If pressure drops, check for “kinks” or
restrictions in line connected to RES port. Line
connected to RES port on governor must be
same diameter, or preferably larger than, lines
connected to UNL port(s) on governor.
B. Remove end cover. Apply 120 psi at control port.
Soap both sides around purge valve to test for
control piston leakage. Leakage should not
exceed a 1" bubble in less than 5 seconds.
C. Test the Holset E Compressor unloader system
with feedback line and check valve for proper
operation. Make certain Holset ECON is not
used with the drop-in version of the air dryer, if
so, remove and retest.
B. Leaking purge valve in air
dryer end cover (control
side).
C. Holset “E” type
compressor.
When installing a Bendix Drop-In air dryer in a
system equipped with a Holset E or QE
compressor, remove the Holset ECON valve along
with its feed back and governor control line.
2. Water and/or Oil in
Supply or Service
Reservoir.
A. Improper discharge line
length or improper line
material. Maximum air
dryer inlet temperature is
exceeded.
B. Air system charged from
outside air source
(outside air not passing
through air dryer).
A. Refer to section entitled Connecting the Air Lines
as well as Appendix A, Table A columns 1 & 2
then and check line size and length.
B. If system must have outside air fill provision,
outside air should pass through air dryer. This
practice should be minimized.