4
4. Close the drain cock on the trailer #1 reservoir, recharge
the system, stop the engine and open the drain cock
on the #2 reservoir. Again, the tractor air system
should bleed down to approximately 45 p.s.i., but the
#1 reservoir on the trailer should remain fully charged.
The spring brakes should remain released on both
the tractor and trailer. Leakage at the open drain cock
should not exceed a 1" bubble in 5 seconds. As this
test is completed, close the drain cock on the trailer
reservoir.
5. If the SR-4
™
spring brake valve does not function
as described above or leakage is excessive, it is
recommended that it be repaired or replaced with a
genuine Bendix service replacement valve.
WARNING! PLEASE READ AND FOLLOW
THESE INSTRUCTIONS TO AVOID PERSONAL
INJURY OR DEATH:
When working on or around a vehicle, the following
general precautions should be observed at all times.
1. Park the vehicle on a level surface, apply the
parking brakes, and always block the wheels.
Always wear safety glasses.
2. Stop the engine and remove ignition key when
working under or around the vehicle. When
working in the engine compartment, the engine
should be shut off and the ignition key should be
removed. Where circumstances require that the
engine be in operation, EXTREME CAUTION should
be used to prevent personal injury resulting from
contact with moving, rotating, leaking, heated or
electrically charged components.
3. Do not attempt to install, remove, disassemble
or assemble a component until you have read
and thoroughly understand the recommended
procedures. Use only the proper tools and observe
all precautions pertaining to use of those tools.
4. If the work is being performed on the vehicle’s
air brake system, or any auxiliary pressurized air
systems, make certain to drain the air pressure
from all reservoirs before beginning ANY work
on the vehicle. If the vehicle is equipped with an
AD-IS
®
air dryer system or a dryer reservoir module,
be sure to drain the purge reservoir.
5. Following the vehicle manufacturer’s recommended
procedures, deactivate the electrical system in a
manner that safely removes all electrical power
from the vehicle.
6. Never exceed manufacturer’s recommended
pressures.
7. Never connect or disconnect a hose or line
containing pressure; it may whip. Never remove
a component or plug unless you are certain all
system pressure has been depleted.
8. Use only genuine Bendix
®
replacement parts,
components and kits. Replacement hardware,
tubing, hose, fi ttings, etc. must be of equivalent
size, type and strength as original equipment and
be designed specifi cally for such applications and
systems.
9. Components with stripped threads or damaged
parts should be replaced rather than repaired. Do
not attempt repairs requiring machining or welding
unless specifi cally stated and approved by the
vehicle and component manufacturer.
10. Prior to returning the vehicle to service, make
certain all components and systems are restored
to their proper operating condition.
11.
For vehicles with Antilock Traction Control (ATC),
the ATC function must be disabled (ATC indicator
lamp should be ON) prior to performing any vehicle
maintenance where one or more wheels on a drive
axle are lifted off the ground and moving.
REMOVAL OF VALVE FROM VEHICLE
1. Check the vehicle wheels and drain all air system
reservoirs completely.
2. Disconnect all supply, delivery and exhaust lines
at the trailer spring brake valve. NOTE: Mark all air
lines and their relation to the spring brake valve for
reconnection.
3. Remove the spring brake valve from the trailer #1
reservoir.
PR-3
™
VALVE REMOVAL AND TEST
(TYPE 1 SR-4
™
VALVE)
1. Remove the PR-3
™
valve from the SR-4
™
valve
assembly.
2. Apply 50 p.s.i. air pressure at the supply port and apply
a soap solution to the delivery port. Leakage of a 1"
bubble in 3 seconds is permissible.
3. Apply 100 p.s.i. air pressure at the delivery port.
Apply a soap solution to the supply port. No leakage
permissible.
4. If the PR-3
™
valve does not function as described above
or leakage is excessive, it is suggested it be exchanged
or replaced at the nearest Bendix distributor. The PR-3
™
valve is not considered as serviceable internally. If
the PR-3
™
valve is disassembled, DO NOT MIX the
PR-3
™
valve parts with similar looking parts in the main
assembly.
