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
FIGURE 3 - TW-4 FIGURE 4 - TW-6
OPERATION
With air pressure a the supply port (Figure 1) and the
plunger in the upward position the valve is in the exhaust
position. The delivery ports are open to atmosphere through
the exhaust passage in the center of the plunger.
When the plunger is depressed by the cam action of the
lever (Figure 1) or by a direct force on a push button (Figure
3) the plunger contacts the inlet valve, closing the exhaust
passage and pushes the inlet valve off the inlet seat in the
body, allowing supply air to flow through the delivery ports
to the controlled device.
PREVENTIVE MAINTENANCE
Every year, 100,000 miles or 1800 operating hours
disassemble, clean and check all parts and replace if
necessary.
SERVICE CHECKS
OPERATING AND LEAKAGE TESTS
Connect a 100 psi air pressure source to the supply port
and connect delivery to an air gauge. (if there are two
delivery ports, plug one.) With the valve in the released
position, check for leakage at the exhaust holes with a soap
solution. No leakage permitted. Place the valve in the applied
position. Supply air pressure should show on the gauge.
Check for leakage at the exhaust holes. No leakage
permitted.
If the TW valve does not function as described or if leakage
occurs, it is recommended that it be replaced with a new
unit or repaired with genuine Bendix parts.
REMOVING
Secure the vehicle with other means than brakes and drain
the reservoirs.
Disconnect all air lines and remove the valve.
INSTALLING
Place valve handle through appropriate hole in panel, place
dial (if used) over handle and install mtg. screws. Connect
air lines.
DISASSEMBLY
Remove operating handle or lever by driving the pin out of
the body (Figure 1) and remove the lever, plunger and plunger
spring. Remove the O-Ring from the plunger.
Remove the supply cap nut, inlet valve and spring. Remove
the 0-Ring from the supply cap nut.
CLEANING AND INSPECTION OF PARTS
Wipe rubber parts clean. Clean plastic and metal parts in
mineral spirits and dry thoroughly. Inspect all rubber parts
for wear or deterioration and replace where necessary. Polish
the inlet seat in the body if nicked or corroded. Inspect all
springs for cracks, distortion or corrosion and replace if
necessary.
ASSEMBLY
Prior to assembly lubricate body bore, plunger, O-Rings,
and cap nut threads with Bendix silicone lubricant BW 650M
Pc. No. 291126.
Place inlet valve in body.
Place inlet valve spring on inlet valve.
Place O-Ring on cap nut and install cap nut.
Install plunger spring from top of body.
Install O-Ring on plunger and install plunger.
SCREW
PUSH
BUTTON
NUT