How To Use The Basic Test; Air Brake System Leakage Test; If No Air Leakage Was Detected In Step D - BENDIX TU-FLO 550 COMPRESSOR Manual

Appendix B continued: Information about the BASIC
Filling in the Checklist for the Bendix
STEP C
- How to Use the BASIC
The Technician uses the chart (label) on the BASIC
test cup to help decide the action to take, based on
the amount of oil found. Use the lower acceptance
line for low air use vehicles, and upper line for high
air use vehicles (from Step A).
BASIC Test Example
™
An oil level of 4 units in a sixty-day period is within the
acceptance area (at or below the line) for both low and
high air use vehicles. Return the vehicle to service.
The Technician looks for the point where the number
of days since the air tanks were drained meets the oil
level. If it is at or below the (low or high use) acceptance
line, the vehicle has passed the test. If the point is
above the line then go to the leakage test.
STEP D - Air Brake System Leakage Test
Park the vehicle on level ground and chock wheels. Build system pressure to governor cut-out
and allow the pressure to stabilize for one minute.
1: Observe the dash gauges for two additional minutes without the service brakes applied.
2: Apply service brakes for two minutes (allow pressure to stabilize) and observe the dash
gauges.
If you see any noticeable decrease of the dash air gauge readings, repair leaks. Repeat
this test to confi rm that air leaks have been repaired and return vehicle to service. Please
repeat BASIC test at next service interval. Note: Air leaks can also be found in the charging
™
system, parking brakes, and/or other components - inspect and repair as necessary.
If no air leakage was detected, and if you are conducting
this test after completing Step C, go to Step E.
STEP E

- If no air leakage was detected in Step D

Replace the compressor.
Note: If the compressor is within warranty period,
please follow standard warranty procedures. Attach
the completed checklist to warranty claim.
A-18
Note: Follow all standard safety precautions. For vehicles using a desiccant air dryer.
™ Test 1. Record days since air
tanks were last drained.
™
If number of days is:
30-60 days (high air
30-90 days (low air
(if the number of days is
unknown, or outside the
™
Test Kit (Bendix P/N 5013711)
®
Air System Inspection Cup (BASIC
2. Record amount
of oil found:
_________ units
_________ days
if oil level is at or below
acceptance line for number
of days
use) or
if oil level is above
acceptance line for number
use)
of days
if oil level is at or below
Otherwise . . .
30-day acceptance line
if oil level is above 30-day
acceptance line
limits above)
Acceptance
X
Sixty days since last air
tank draining
™ ) Test
3. Action to
take
System OK.
Return to service.
Go to Step D
System OK.
Return to service.
Stop inspection.
Test again
after 30 days.
See Footnote 2.
Lines
Oil
Level
Decision point
Air leakage is the number one
cause of compressors having
to pump excessive amounts of
air, in turn run too hot and pass
oil vapor along into the system.
Here the Technician conducts a
four-minute test to see if leakage
is a problem with the vehicle
being tested.
The Technician only reaches
Step E if the amount of oil
found, or the amount of time
since the air tanks were last
drained exceeds the acceptance
level, AND the vehicle passes
the four-minute leakage test
(no noticeable leakage was
detected).
STOP
TEST
STOP
TEST
STOP
+ CK.