Bendix Commercial Vehicle Systems BEPA (FORD) 15X4 CAM BRAKE 5/09 - Manual (Page 6)

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7. BRAKE DRUMS
A. Inspect drums for cracks, heat checking, glazing,
grooving, severe out-of-round condition or bell
mouthing (must not exceed .025 T.I.R.). Replace
any cracked drums. It is recommended that drums
be turned at reline to prevent hot spotting and
achieve quicker, more complete burnishing of the
new lining.
B. Measure the drum I.D. to be sure the maximum limit
allowed (stamped on drum) has not been exceeded,
due to wear or machining.
8. MANUAL SLACK ADJUSTER
A. Check for cracks in the body and arm of the slack
adjuster.
B. Check for spline wear. The amount of backlash in
the slack adjuster to camshaft should be no more
than .094" measured 6" from centerline of the cam
shaft (See Figure 8).
CAUTION: If the vehicle is equipped with spring
brakes, refer to manufacturer’s instructions. High
spring load, if not handled properly, may result in
serious injury or death may result.
ASSEMBLY (SEE FIGURE 2)
1. Install the spider onto the axle fl ange using the fi ve
bolts, three 5/8" studs, lockwashers and nuts. Be sure
spider is properly oriented as noted during disassembly.
Tighten mounting bolts to vehicle manufacturer’s
specifi cations.
2. If cam shaft bushings were removed, replace with
new bushings. Drive into place using Owatonna 630-7
piloted driver or similar tool, taking care not to damage
or distort the I.D. of the bushings. NOTE: Bushings are
located at each end of cam shaft tube.
3. Install new cam shaft grease seals in the end of the
cam tube and chamber bracket. Use Owatonna 630-7
piloted driver or similar tool to install grease seals.
CAUTION: The lip of the grease seals must be installed
correctly to prevent possible damage. The lip of the seal
that is installed in the cam end must enter the opening
fi rst. The lip of the seal that is installed in the opposite
end of the cam tube must enter last (See Figure 9).
4. Install the actuator bracket and cam tube onto the
spider using four cap screws and lockwashers. Torque
to 70-80 ft. lbs. Secure the actuator to the bracket
using the two nuts and washers. Torque to vehicle
manufacturer’s specifi cation.
5. If removed, reinstall the dust shields. Tighten the six cap
screws and lockwashers to 90-110 in. lbs. torque.
6. Coat cam shaft journals with light fi lm of chassis lube.
Do not coat “S”-cam head. Install the cam shaft into
the cam tube. Be careful not to damage the grease
seals.
.094”
FIGURE 8 - CHECKING SLACK ADJUSTER BACKLASH
6”
C. Check ability to rotate the adjusting nut at least
one complete revolution in each direction. Force
required to rotate the adjusting nut should not
exceed 15 ft. lbs. NOTE: If any of the above
conditions are found, replace the slack adjuster.
Do not attempt to repair.
9. AUTOMATIC SLACK ADJUSTERS
A. Consult manufacturer’s service information. (For
information on Bendix Automatic Slack Adjusters,
see Service Data sheet SD-05-1200, formerly
SD-05-1).
10. ACTUATORS
A. Check for cracked housing, loose mounting
studs.
B. Check for damage to the push rod, and push rod
boot (if so equipped).
C. Check for broken push rod return spring.
D. Check for excessive wear on yoke, yoke pin, and
slack adjuster yoke pin hole or bushing. There
should be no more than .031 combined free play
in these components.
FIGURE 9 - SEAL INSTALLATION
SLACK ADJUSTER END
NOTE: BOTH LIP SEALS POINT THE SAME DIRECTION LIP
TOWARD SLACK ADJUSTER
LIP SEAL
ACTUATOR BRACKET
AND CAM TUBE
CAM END
LIP SEAL