PREVOST X3-45 Multiplex, Руководство по обслуживанию

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PP-1 20,30,40
or 60 psi
PP-2 40 psi
PP-5 40 psi 18 psi
RD-3 Must be held
manually
PP-8 Will remain in
either position
2. With 120 psi supply pressure, and the button pulled out
(exhaust position), leakage at the exhaust port should
not exceed a 1" bubble in five seconds; at the plunger
stem a 1" bubble in five seconds. There should be no
leakage between upper and lower body.
3. Push the button in (applied position). Leakage at the
exhaust port should not exceed a 1" bubble in 3 sec-
onds; at the plunger a 1" bubble in three seconds. (The
RD-3 will have to be manually held in this position.)
4. Reduce the supply pressure. At a pressure from 60 to
20 psi depending on the spring installed the button should
pop out automatically, exhausting the delivery volume.
(This does not apply to the RD-3, PP-8 or some PP-
1’s).
PP-5
1. Proceed as for PP-1 through Step 3.
2. Connect a modulated source of air pressure to the pilot
air inlet. With the button pushed in (applied position)
with 125 psi supply pressure and a gradually increasing
pressure applied at the pilot air port the valve should
move to the release position with a pilot pressure of not
more than 18 psi. Leakage in this mode should not ex-
ceed a 1" bubble in three seconds at the exhaust port
and a 1" bubble in five seconds at the plunger stem.
PP-2
1. Proceed as for PP-1 through Step 1.
2. With the button pulled out (exhaust position), leakage
at the brake valve port or at the plunger stem should not
exceed a 1" bubble in five seconds.
3. Push the button in. Supply pressure should be present
in the delivery volume. Leakage at the exhaust port or
around the plunger stem should not exceed a 1" bubble
in five seconds.
4. Pull the button out and apply supply pressure at the
brake valve port. Supply pressure should be present in
the delivery volume and leakage at the exhaust port
should not exceed a 1" bubble in five seconds.
Note: If any of the above push-pull valves do not function as
described or if leakage is excessive, it is recommended
they be returned to our nearest authorized distributor for a
factory rebuilt or new valve.
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 park-
ing brakes, and always block the wheels.
2. Stop the engine when working around the vehicle.
INSTALLING
1. Install valve in panel, securing with the Panel Mounting
Nut.
2. Reconnect the air lines using marks made during removal
as a guide.
3. Install the operating button. Secure the operating button
by installing the Button Roll Pin.
DISASSEMBLY: PP-1, PP-8 AND RD-3
1. Remove the two cap screws (3) which retain the lower
cover and remove cover. Remove the sealing ring (4).
2. Insert a small punch through the roll pin hole in the stem
and remove the lock nut (5).
3. Remove inlet-exhaust valve (6) and plunger (7) and spring
(8) (if any).
4. Remove o-ring (9) from plunger.
DISASSEMBLY: PP-5
1. Perform same operations as for PP-1.
2. Remove inlet seal (10) in Figure 4 from lower cover.
Remove the ring diaphragm (4) from the inlet seat.
3. Remove piston (11) Figure 4 and o-ring (2).
DISASSEMBLY: PP-2
1. Insert a small punch through the roll pin hole in the plunger
and remove the lock nut (1) from the plunger.
2. Withdraw the plunger and remove the spring (9) and o-
ring (8).
3. Remove the two machine screws (2) and remove the
lower cover (3).
4. Remove the inlet-exhaust valve (4), and piston (5).
5. Remove o-rings (6 & 7) from piston.
OPERATING AND LEAKAGE TESTS
PP-1, PP-8, RD-3
1. An accurate test gauge should be tee’d into the supply
line and a means of controlling the supply pressure pro-
vided. Apply a 120 psi air source to the supply port. A
small volume reservoir (e.g. 90 cu. in.) with a gauge
should be connected to the delivery port.
AUTOMATIC MOMENTARY PILOT TRIP NON-
EXHUAST APPLY FEATURE AUTOMATIC