Bendix Commercial Vehicle Systems AD-IS EVERFLOW ASSEMBLY - Manual (Page 7)

7
TESTING THE 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 AD-IS ® air dryer purges with an audible burst of
air, followed immediately by approximately 30 seconds
of air fl owing out of the purge valve.
3. “Fan” the service brakes 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 assure that the AD-IS ® air dryer will not
cycle excessively.
See Bendix publication BW5057 “Air Brake Handbook" for
additional information.
BRAKING SYSTEM PROTECTION
The 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 AD-IS
® 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 pages
5-6 in this document.
Make sure that all residual pressure has been released and
the air dryer purge reservoir has been drained to 0 p.s.i.,
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-fi tting into the port.
Using any adapters necessary, reinstall the safety valve
in one of the branches of the T-fi tting. Using any adapters
necessary, install the air supply line into the remaining
T-fi tting port. After testing the T-fi tting 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 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.
DELIVERY CHECK VALVE CLEANING PROCEDURE
(Note: This is only required if system pressure does not
build after temporary bypass is completed.)
Refer to Figure 6 throughout this procedure. Depressurize
the air brake system following the General Safety
FIGURE 4- PRESSURE PROTECTION VALVE LOCATIONS
PRESSURE
PROTECTION
VALVE
LOCATIONS
AD-IS ®
AIR DRYER
GOVERNORS
ARE NON-
ADJUSTABLE
AND FEATURE A
BREATHER VALVE
IN THIS PORT
WARNING:
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.