PREVOST X3-45 Multiplex, Maintenance Manual

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m a i n local global o p e r a t i o n t r o u b l e -
m e n u s e a r c h s e a r c h s h o o t i n g
1. Coat exhaust port with soap solution; leakage of a one
(1) inch bubble in three (3) seconds is permitted.
2. Coat body and cover with soap solution. No leakage perm
itted between body and cover.
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, or repaired with genuine Bendix parts.
REMOVING AND INSTALLING
REMOVING
Block vehicle wheels and/or hold vehicle by means other
than air brakes.
Drain all air brake system reservoirs.
Disconnect air lines from valve.
Remove mounting bolts, then valve.
INSTALLING
Mount valve with exhaust port pointing down; securely tighten
mounting bolts.
Connect air lines to valve (brake valve application line to top
port; brake chamber line to side ports.)
DISASSEMBLY
QR VALVE
1. Using wrench on square portion of exhaust port, remove
cover.
2. Remove spring, spring seat and diaphragm. Remove cover
O-Ring.
QR-1 VALVE
1. Remove four screws.
2. Remove spring and spring seat {if so equipped).
3. Remove diaphragm.
4. Remove cover O-Ring.
CLEANING AND INSPECTION
Clean all metal parts in mineral spirits. Wipe all rubber parts
clean.
It is recommended that all rubber parts and any other part
showing signs of wear or deterioration be replaced with genu-
ine Bendix parts.
ASSEMBLY
QR VALVE
1. Position spring seat over the diaphragm and then install
into body.
2. Install spring and cover O-Ring.
3. Install cover; tighten securely. (Torque to 150-400 inch
pounds. )
QR-1 VALVE
1. If valve is equipped within spring and spring seat:
a. Position spring in body.
b. Position diaphragm over spring seat.
c. Install O-Ring in cover groove; install cover and tighten
screws evenly and securely. (Torque to 30-60 inch
pounds.)
2. If valve is not equipped with spring and spring seat:
a. Install diaphragm.
b. Install O-Ring in cover groove; install cover and tighten
screws evenly and securely. (Torque to 30-60 inch
pounds.)
3. Perform tests as outlined in “Operating and Leakage
Tests” section.
IMPORTANT! PLEASE READ
When working on or around a vehicle, the following general
precautions should be observed:
1. Park the vehicle on a level surface, apply the parking
brakes, and always block the wheels.
2. Stop the engine when working around the vehicle.
3. If the vehicle is equipped with air brakes, make certain
to drain the air pressure from all reservoirs before
beginning ANY work on the vehicle.
4. Following the vehicle manufacturer’s recommended
procedures, deactivate the electrical system in a manner
that removes all electrical power from the vehicle.
5. When working in the engine compartment the engine
should be shut off. 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.
6. 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.
7. Never exceed recommended pressures and always wear
safety glasses.
8. 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.
9. Use only genuine Bendix replacement parts,
components, and kits. Replacement hardware, tubing,
hose, fittings, etc. should be of equivalent size, type,
and strength as original equipment and be designed
specifically for such applications and systems.
10. Components with stripped threads or damaged parts
should be replaced rather than repaired. Repairs requiring
machining or welding should not be attempted unless
specifically approved and stated by the vehicle or
component manufacturer.
11. Prior to returning the vehicle to service, make certain all
components and systems are restored to their proper
operating condition.
BW1442 © AlliedSignal Truck Brake Systems Co. 1/1999. Printed in USA.