36
MAINTENANCE
Check the brake adjustment frequently
during the first 500 miles after relining.
Overloading or using only the trailer brakes
to stop the complete tractor-trailer unit will
cause the heat absorption capacity of the
brake to be exceeded. Hotter brake linings
and drums, longer stopping distances, and
shorter brake lining life will result.
CAUTION
Trouble Analysis for Air Brakes
Trouble
Probable Cause
Corrective Action
No brakes or intermittent brakes.
Brake air system improperly connected.
Reconnect correctly.
Relay emergency valve contains
Clean valve.
water or oil.
Tractor protection valve malfunction.
Repair or replace valve.
Restricted tubing or hose line.
Locate and remove restriction.
No air pressure due to:
a. Broken line.
Locate leak and repair.
b. Failure in tractor air supply.
Troubleshoot tractor air system.
Single brake dragging or locked.
Broken component within brakes:
Replace broken part.
a. Retract spring.
b. Cam roller.
c. Shoe.
d. Lining fasteners.
e. Anchor pin.
f. Spider.
Flat spot on cam roller or camshaft
Replace defective parts. DO NOT
lubricate mating surfaces of cam or
cam roller.
Improper adjustment.
Adjust slack adjusters.
Spider bushing or cam bracket
Lubricate or replace bushing.
bushing binding.
Improper Lubrication
Lubricate
Worn anchor pin bushing.
Replace bushing.
Brake drum distortion.
Repair or replace drum.
Broken brake chamber spring.
Replace spring.
Brake chamber pushrod binding.
Realign brake chamber bracket or
install correct brake chamber.
(continued)