Bendix Commercial Vehicle Systems BA-921 SMC COMPRESSOR - Manual (Page 19)

19 A-6
Symptom: What it may indicate: What you should do:
4.0 Oil in Supply or
Service Reservoir
(air dryer installed)
(If a maintained Bendix ®
PuraGuard ® system
fi lter or Bendix ®
PuraGuard QC ™ oil
coalescing
fi lter is installed, call
1-800-AIR-BRAKE
(1-800-247-2725) and
speak to a Tech Team
member.)
(a) If air brake charging system mainte-
nance has not been performed.
That is, reservoir(s) have not been
drained per the schedule in Table
A on page A-3, Column 4 and/or
the air dryer maintenance has not
been performed as in Column 3.
(b) If the vehicle maintenance has
been performed as recommended
in Table A on page
A-3, some oil in
the reservoirs is normal.
Drain all air tanks and check vehicle at next
service interval using the Bendix ® BASIC ™
test. See Table A on page A-3, column 3
and 4, for recommended service schedule.
Drain all air tanks into Bendix ® BASIC ™ test
cup (Bendix Air System Inspection Cup).
If less than one unit of reservoir contents
is found, the vehicle can be returned to
service. Note: If more than one oil unit
of water (or a cloudy emulsion mixture)
is present, change the vehicle's air dryer,
check for air system leakage (Test 2, on
page A-14), stop inspection and check
again at the next service interval.
See the BASIC ™ test kit for full details.
If less than one "oil unit" of water (or water/
cloudy emulsion mixture) is present, use the
BASIC
™ cup chart on the label of the cup to
determine if the amount of oil found is within
the acceptable level.
 If within the normal range, return the
vehicle to service. For vehicles with
accessories that are sensitive to small
amounts of oil, consider a Bendix
®
PuraGuard QC ™ oil coalescing fi lter.
 If outside the normal range go to Symptom
4.0(c).
Also see the Table A on page A-3, column
3 for recommended air dryer cartridge
replacement schedule.
Maintenance
Go to Test 2 on page A-14.
See Table A, column 1, on page A-3 for
recommended compressor sizes.
 If the compressor is "too small" for
the vehicle's role (for example, where
a vehicle's use has changed or service
conditions exceed the original vehicle
or engine OE spec's) then upgrade the
compressor. Note: The costs incurred (e.g.
installing a larger capacity compressor, etc.)
are not covered under original compressor
warranty.
 If the compressor is correct for the
vehicle, go to Symptom 4.0 (e).
Duty cycle too high
See Table A, on page
A-3, for maintenance
schedule information.
Drain all air tanks (reservoirs)
into the Bendix
® BASIC ™ test
cup. (Bendix kit P/N 5013711).
The duty cycle is the ratio of time the compressor spends
building air to total engine running time. Air compressors
are designed to build air (to "run loaded") up to 25% of the
time. Higher duty cycles cause conditions that affect air
brake charging system performance which may require
additional maintenance. Factors that add to the duty cycle
are: air suspension, additional air accessories, use of an
undersized compressor, frequent stops, excessive leakage
from fi ttings, connections, lines, chambers or valves, etc.
(c) Air brake system leakage. 
(d) Compressor may be undersized for
the application.
(a)