Air Brake Test and Slack Adjusters
Start Engine and build air until compressor cuts
out. Depress service (Foot) brake until the air compressor cuts in (should
be about 85 psi.). Let air build until it cuts out (should not exceed
130psi). Wait for compressor to cut in between brake applications.
Static Brake Test
Start in a level location, or block a wheel to
keep from rolling. Place the transmission in neutral. Turn engine off and
release parking brake. Keep foot off service brake. Air loss should not
exceed 2psi in one minute.
Applied Brake Test
MAKE FULL (Foot) BRAKE APPLICATION (BE
SURE you have released your park brake before you do this or you will
damage the system.) Hold the pedal all the way to the bottom for
one minute. Watch your air gages as they should not move (Allowable loss
in this mode for 60 seconds is 3 psi. Listen for audible leaks as you wait
for the 60 seconds to expire. After 60 seconds release the pedal. (YOUR
AUTO SLACK ADJUSTERS WILL SET UP AUTOMATICALLY DURING THIS PROCEDURE.)
Air Warning Device
Turn ignition switch to on. DO NOT START ENGINE.
Observe the air pressure gauge and pump service bake until you can see the
warning light come on and/or hear the warning buzzer. The low warning must
come on around 60 psi.
Brake System Test
Turn off the ignition and then reduce the air
pressure by pumping the brake pedal until emergency (parking) brake handle
pops up (should be below 45 psi). Start the engine put transmission in
gear and try to move the coach slowly
against the emergency brake with low air pressure. Caution
should be used so as not to apply too much pressure against the brakes and
Place the transmission in neutral. Run engine at 1000rpm using your cruise setting. Time 3 minuets. In this time your air pressure should be up to between 50 and 90psi. This will tell you your compressor is functioning properly.
Allow air pressure to build up until it cuts out.
Put coach in gear. Release the parking brake. Move the coach slowly
and apply the emergency (parking) brake. This test checks your emergency
Check Service Brakes
Release Parking Brake. Set coach on motion and
apply service (foot) brake firmly to see if the steering wheel pulls to
the left or right.
(Auto slack adjusters
are used to maintain proper brake chamber stroke and lining to drum
clearance during normal operation. The entire slack adjuster operates as a
unit rotating with the brake camshaft as brakes are applied or released.
THE MOST EFFICIENT BRAKING OCCURS WHEN PUSH ROD TRAVEL IS HELD TO A