4-8.2
Spring Air Brake
Check for faulty units. Check the condensation
holes on the underside of the brake chambers to
make sure they are open. The spring brake has
two brake chambers, a service chamber and an
emergency chamber or spring chamber. Service
brake chambers should be disassembled and
cleaned at 50,000 miles or yearly. The diaphragm
and any marginal parts should be replaced. When
replacing the service diaphragm, replace the corre-
sponding parts for the other chamber on the same
axle (to aid in even brake application and release).
Examine yoke pin for wear and replace as neces-
sary. The spring chamber should not be serviced.
Replace entire unit (both service and spring cham-
ber) if spring chamber becomes faulty.
WARNING
THE SPRING BRAKE CHAMBER EM-
PLOYS A SPRING WITH HIGH FORCES.
SERVICE SHOULD NOT BE AT-
TEMPTED. SERIOUS INJURY OR
DEATH MAY RESULT.
4-8.3
Replacing the Spring Air Brake Unit
a. Caging the Power Spring in the Spring
Chamber
1.
Chock the trailer wheels.
2.
Remove dust cap from the rear of the spring
brake chamber
(See Figure 4-10).
3.
Remove the release bolt from it’s holding
brackets. Insert it into the spring brake
chamber until it can be rotated and hooked
into place.
DO NOT USE AN IMPACT
WRENCH TO CAGE THE SPRING
BRAKE!
4.
Turn the nut on the release bolt until the
spring brake is caged. This should be 2-1/4
to 2-1/2 inches of release bolt extension.
5.
The brakes should now be released. Do
not operate loaded trailer with brake
manually released.
b. Uncaging the Power Spring in the Spring
Chamber
1.
Chock the trailer wheels.
2.
Turn the nut on the release bolt until the
spring is released. Remove the release bolt
and store it in its brackets.
3.
Snap the dust cap back in place on the
chamber.
c. Removal of Brake Unit
1.
Chock all tractor and trailer wheels and
drain the air system.
2.
Mark the brake chamber for proper air line
port alignment for reassembly.
3.
CAGE THE POWER SPRING following the
steps outlined in
Section 4-8.3 a.
4.
Disconnect the slack adjuster from the
connecting rod by removing the clevis pin
(See Figure 4-11).
5.
Mark all air service lines for proper
re-installation and disconnect from the brake
chamber.
6.
Remove the brake chamber from the axle
brackets.
4-14
Figure 4-9 Brake Lining Wear
Содержание 345C
Страница 3: ...MODEL 345C TRAILER OPERATOR S MANUAL PURCHASED FROM DATE ADDRESS PHONE NO SERIAL NO i...
Страница 8: ......
Страница 12: ......
Страница 22: ...3 10 Figure 3 4 Steps for Loading and Unloading...
Страница 26: ...3 14 Figure 3 7 Rear Impact Guard and Antilock Brake System...
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Страница 35: ...4 5 Figure 4 2 345C Wiring Diagram...
Страница 36: ...4 6 Figure 4 3 Remote Wiring Diagram...
Страница 41: ...4 11 Figure 4 5 Examples of Camber Figure 4 6 Checking Axle for Bend...
Страница 46: ...4 16 Figure 4 10 Axle and Brake Assembly...
Страница 63: ...5 9 NOTES...
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