Check vehicle on level ground if possible, set parking brake, block wheels, ensure that all tanks are drained. Suggested maximum time required for this pre-trip inspection is 15 minutes.

CIRCLE CHECK

1. Check security and condition of compressor and belts under hood.
2. Check condition and security of hoses and flex lines.
3. Pull all slack adjusters manually (use pry bar if necessary). Check for travel, mechanical condition, wear.

NOTE: A brake adjustment (S cam type only) will be required as part of the air test examination.

BUILD UP AIR PRESSURE, WATCHING THAT THE:

1. Warning device(s) cuts out at approximately 60 P.S.I.
2. Pressure builds from 50-90 P.S.I. within five minutes.
3. Governor cuts out between 105 P.S.I. minimum and 125 P.S.I. maximum.

AT MAXIMUM PRESSURE:

1. Release parking brakes (if equipped) to prevent compounding.
2. Shut off motor.
3. Make a full brake application. Check for:
   1. air loss less than 4 P.S.I. drop within one minute;
   2. audible air leaks.

START MOTOR AND FAN BRAKES

1. Stop fanning at 80 P.S.I. to see if governor has cut in (needle should start to climb).
2. Continue fanning:
   1. warning device should start operating at approximately 60 P.S.I.;
   2. parking brake should apply at 45-20 P.S.I. if plumbed into main reservoir tanks.

REBUILD PRESSURE TO MAXIMUM

1. With parking brakes set, remove wheel chocks.
2. Gently tug test against parking brakes in low gear.
3. Release parking brakes and move vehicle ahead slowly and make a service brake application to check the brake response.