PREVOST LE MIRAGE XLII BUS SHELLS, Руководство по обслуживанию

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opening the inlet to deliver air to the spring brake cavity
as described under the section of this manual entitled
Application .
PREVENTIVE MAINTENANCE
Important: Review the warranty policy before performing
any intrusive maintenance procedures. An extended war-
ranty may be voided if intrusive maintenance is performed
during this period.
Because no two vehicles operate under identical condi-
tions, maintenance and maintenance intervals will vary.
Experience is a valuable guide in determining the best
maintenance interval for any one particular operation.
1. Every three months or 25,000 miles or 900 operating
hours check for proper operation.
2. Every twelve months or 100,000 miles or 3600 operat-
ing hours: disassemble valve, clean parts with mineral
spirits. Replace all rubber parts and any part worn or
damaged. Check for proper operation before placing
vehicle in service.
OPERATIONAL AND LEAKAGE TEST
1. Chock the wheels, fully charge air brake system and
adjust the brakes.
2. Make several brake applications and check for prompt
application and release at each wheel.
3. Check for inlet valve and o-ring leakage.
A. Make this check with the service brakes released
when the R-12 or R-14 is used to control the service
brakes.
B. Make the check with the spring brakes applied
(PARK) when the R-14 is used to control the spring
brakes. Coat the exhaust port and the area around
the retaining ring with a soap solution; a 1 inch
bubble in 3 seconds leakage is permitted.
4. Check for exhaust valve leakage.
A. Make this check with the service brakes fully applied
if the R-12 or R-14 control the service brakes.
B. Make this check with the spring brakes fully re-
leased if the R-14 is used to control the spring
brakes. Coat the exhaust port with a soap solution;
a 1 inch bubble in 3 seconds leakage is permitted.
Coat the outside of the valve where the cover joins
the body to check for seal ring leakage; no leakage
is permitted.
5. If the R-14 is used to control the spring brakes, place
the park control in the released position and coat the
balance port with a soap solution to check the dia-
phragm and its seat. Leakage equivalent to a 1 inch
bubble in 3 seconds is permitted.
Note: If the anti-compound feature is in use, the line
attached to the balance port must be disconnected to
perform this test.
If the valves do not function as described above, or if leak-
age is excessive, it is recommended that the valves be
replaced with new or remanufactured units or repaired with
genuine Bendix parts, available at any authorized Bendix
parts outlet.
REMOVAL AND INSTALLATION
REMOVAL
1. Block and hold vehicle by means other than air brakes.
2. Drain air brake system reservoirs.
3. If entire valve is to be removed, identify air lines to
facilitate installation.
4. Disconnect air lines from valve*.
5. Remove valve from reservoir or if remotely mounted,
remove mounting bolts and then valve.
*It is generally not necessary to remove entire valve to
service the inlet/exhaust valve. The inlet/exhaust valve
insert can be removed by removing the snap ring, exhaust
cover assembly and then inlet/exhaust valve.
Caution: Drain all reservoirs before attempting to remove
the inlet exhaust valve.
DISASSEMBLY
Note: Prior to disassembly, mark the location of the mount-
ing bracket to the cover and the cover to the body.
1. Remove the four (4) cap screws and lockwashers
securing the cover to the body.
2. Remove the cover, sealing ring, and mounting bracket.
3. Remove the piston and o-ring from the body.
4. While depressing the exhaust cover, remove the
retaining ring and slowly relax the spring beneath the
exhaust cover.
5. Remove the exhaust cover assembly and o-rings.
6. Remove the inlet/exhaust valve return spring from the
body.
7. Remove the inlet/exhaust valve from the body.
8. Remove the valve retainer from the inlet/exhaust valve.
9. Remove the Phillips head screw and exhaust cover
from the R-14 cover.
10. Remove the service port cap nut and o-ring from the
R-14.
11. Remove the diaphragm from the R-14 cover.