Bendix Commercial Vehicle Systems D-2 GOVERNOR 5/10 - Manual (Page 3)

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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, fi ttings, etc. must be of equivalent
size, type and strength as original equipment and
be designed specifi cally 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 specifi cally 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.
11. For vehicles with Automatic Traction Control (ATC)
,
the ATC function must be disabled (ATC indicator
lamp should be ON) prior to performing any vehicle
maintenance where one or more wheels on a drive
axle are lifted off the ground and moving.
REMOVING AND INSTALLING
REMOVING
1. Block and hold vehicle by means other than air
brakes.
2. Drain air brake system.
3. If the governor is compressor-mounted type, disconnect
reservoir air line. If the governor is remote-mounted,
disconnect both the unloader and reservoir air lines.
4. Remove governor mounting bolts, then governor.
Caution: Prior to disassembly, it is required to have the
proper maintenance kit available to replace parts to be
discarded during disassembly.
DISASSEMBLY
1. Clean the governor exterior of dirt and grease.
2. If the governor cover is marked nonadjustable and the
adjusting screw has been sheared off, this is a non-
serviceable governor and must be replaced with a new
or remanufactured unit.
3. If the governor has a blue nonmetallic cover, (refer to
Figure 2) hold governor with one hand, with the other
hand grip cover from the top and pull up with thumb until
cover disengages from the governor body. If top cover
on governor is made of rubber or clear nonmetallic
material unscrew cover until it releases from the
adjusting screw (4) of governor. Remove o-ring (20,
Figure 2) if present. Note: O-ring (20) is used on Hi-
Temp and waterproof governors only.
4. With a pair of retaining ring pliers, remove the spring
assembly retaining ring (1) and save.
5. Pull the adjusting screw (4) and spring assembly out
of the governor body (2).
Note: Disassembly of the spring assembly normally is
not required. (Reuse and do not wash the assembly
because lubrication may be removed.) If Disassembly
of the spring assembly is necessary, the following
instructions apply; otherwise, proceed to Step 6.
Remove the lock nut (3), then the hex-shaped upper
spring seat (16) from the adjusting screw (4). Remove
the pressure setting spring (17), lower spring seat (19),
spring guide (18) and the other lower spring seat (19)
from the adjusting screw (4).
6. Gently tap the open end of the valve body on a fl at
surface to remove the exhaust stem (5), the exhaust
stem spring (6), and piston assembly (11). Items 5 and
11 may be made of metal or nonmetallic material.
7. Remove and discard the two o-rings (8) on the piston
O.D. and with a hooked wire remove and discard the
o-ring (12) from the piston l.D. On nonmetallic piston,
washer (13) and retaining ring (14) may be removed
to facilitate removal of o-ring (12).