Bendix Commercial Vehicle Systems AD-IS EVERFLOW - Manual (Page 9)

9
TESTING THE BENDIX ® AD-IS ® EVERFLOW ®
ASSEMBLY
Before placing the vehicle in service, perform the following
tests.
1. Close all reservoir drain valves.
2. Build up system pressure to governor cut-out and note
that one Bendix ® AD-IS ® air dryer purges with an audible
burst of air, followed immediately by approximately 30
seconds of air flowing out of the purge valve.
3. Apply and release the service brakes several times to
reduce system air pressure to governor cut-in. Note
that the system once again builds to full pressure and is
followed by a purge at the other AD-IS air dryer exhaust.
4. It is recommended that the total air system be tested
for leakage to ensure that the AD-IS air dryer will not
cycle excessively.
See Bendix publication BW5057 “Air Brake Handbook" for
additional information.
BRAKING SYSTEM PROTECTION
The Bendix ® AD-IS ® EverFlow ® assembly allows the system
to maintain one brake circuit up to about 100 psi even after
a pressure loss in the other brake circuit. This allows a
vehicle to be moved (in an emergency), but with reduced
braking capacity. Compare this to a conventional system
where a loss of pressure in one service tank leaves the
vehicle with a limited number of reduced braking capacity
applications before the parking brakes automatically apply
and stay on.
ROADSIDE INSPECTION
In the event of a roadside inspection, the system behavior
will be as follows: When the system is charged to
governor cut-out, and then one reservoir drain valve is
opened, initially both reservoir gauges will fall, however,
the EverFlow assembly primary and secondary pressure
protection valves will close at pressures above 70 psi,
protecting the remaining brake circuit from further loss
of pressure.
TEMPORARY AIR DRYER BYPASS
To temporarily bypass the EverFlow assembly, the
following procedure needs to be followed.
Follow the General Safety Guidelines outlined on page 2
in this document.
Make sure that all residual pressure has been released
and the air dryer purge reservoir has been drained to 0
psi, then remove the air supply line from the compressor
to the inlet port (1 IN). Remove the safety valve from the
AD-IS air dryer body (see Figure 1 for location). Note that
a short puff of trapped air may vent from the safety valve
port when the valve is being removed. Install a T-fitting
into the port.
Using any adapters necessary, reinstall the safety valve in
one of the branches of the T-fitting. Using any adapters
necessary, install the air supply line into the remaining
T-fitting port. After testing the T-fitting for any air leakage,
by using a soap solution after charging to system cut-out
pressure (a 1” bubble in 10 seconds is acceptable), the
vehicle may be returned to temporary service.
Note: This is a temporary bypass of the air dryer, and
full repair of the unit must be carried out at the earliest
opportunity. With the EverFlow assembly removed from
the system, contaminants will be entering the air system:
reservoirs will need to be manually drained daily until the
repairs are completed. At the end of each working day,
park vehicle and slowly drain pressure through the drain
valves – leave open to the atmosphere, for several hours
if possible. When repairs are carried out, be sure to check
that all reservoirs (including the air dryer purge reservoir)
are emptied of all contaminants.
If after bypassing the EverFlow
assembly the system
pressure still does not build, use the following procedure
to remove, clean and reinstall the delivery check valve.
FIGURE 6 - PRESSURE PROTECTION VALVE LOCATIONS
PRESSURE
PROTECTION
VALVE
LOCATIONS
BENDIX ® AD-IS ®
AIR DRYER
GOVERNORS
ARE NON-
ADJUSTABLE
AND FEATURE A
BREATHER VALVE
IN THIS PORT
DO NOT ATTEMPT TO ADJUST OR
SERVICE THE PRESSURE PROTECTION
VALVES. INCORRECT PRESSURE
PROTECTION VALVE SETTINGS CAN
RESULT IN AUTOMATIC APPLICATION
OF VEHICLE SPRING BRAKES WITHOUT
PRIOR WARNING.