8
LEAKAGE TEST
Place the park control valve in the “release” position; using
a soap solution, coat all ports including the exhaust port. A
1" bubble in 3 seconds is permitted (175 SCCM).
If the valve does not function as described, or if leakage is
excessive, it is recommended that it be replaced with a new
or remanufactured unit available from a Bendix parts outlet.
DO NOT ATTEMPT TO DISASSEMBLE THE SR-7
™
VALVE. THE VALVE CONTAINS HIGH SPRING FORCES
THAT COULD RESULT IN PERSONAL INJURY IF
DISASSEMBLY IS ATTEMPTED!
SERVICING THE SR-7
™
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, fittings, etc. must be of equivalent
size, type and strength as original equipment and
be designed specifically 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 specifically 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.
VALVE REMOVAL
1. Prior to removing the SR-7
™
valve, apply the parking
brakes and drain all the vehicle reservoirs.
2. Identify all air lines before disconnecting.
3. Remove the two mounting nuts that secure the valve to
the frame rail and remove the valve.
VALVE INSTALLATION
1. Align the mounting studs with the mounting holes on
the vehicle frame rail. Tighten the mounting nuts to
180-220 in. lbs.
2. Install the valve onto the vehicle ensuring all ports are
connected as marked during disassembly.
TESTING THE REPLACEMENT SR-7
™
SPRING
BRAKE MODULATING VALVE
Perform operating and leakage tests as outlined in “Operating
Tests” section.
BW2271 © 2004 Bendix Commercial Vehicle Systems LLC 3/2004. Printed in U.S.A. All rights reserved.
