chambers perform the work on the carrier brake mechanism. Air brake troubles, in general, are indicated by:
NO BRAKES. Due to no air pressure, broken lines or connections, bad leak or defective brake valve.
SLOW BRAKE APPLICATION. Caused by slack brakes, low air pressure, faulty lines or lack of lubrication in the brake
mechanism.
SLOW BRAKE RELEASE. May be due to broken brake release springs, binding of the brake rigging or defective brake
valve.
BRAKES GRAB. Due to grease on lining, out-of-round brake drums or defective brake valve.
UNEVEN BRAKES. Need adjustment or relining; has grease on lining; leaky brake chamber or brake drum is out-of-
round.
LOW AIR PRESSURE. Due to bad leak, reservoir drain cock being open, governor not being adjusted properly, defective
air gage or worn air compressor.
SAFETY VALVE "BLOWS-OFF".
Air pressure in the system is above normal due to the governor being out of
adjustment.
EXCESSIVE OIL OR WATER IN SYSTEM. Due to not draining the reservoir often enough, worn compressor rings or dirty
air strainer.
PARKING AND SPRING BRAKES
BRAKES NOT HOLDING. Power spring not fully uncage. Spring not fully applying or actuating. Caging bolt damaged or
power spring broken. Hold off air not fully releasing.
BRAKES DRAGGING. Low spring hold off pressure (should be -70 psi minimum). Leaking air lines or seals. Plungers
tight or sticking. Brake shoe springs not fully returning due to internal binding or breakage.
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