Even P buses have bad days!

[davidbrady]

Mike,

Excellent info. The guys over on POG were also talking about this bus fire. Along with the two causes mentioned in this thread they add the possibility of a parking brake not fully releasing and the possibility of lack of lubricant in the hub. Prevosts use parking brake canisters on both the drive and the tag wheels. The poster suggested doing the normal DOT leak down air brake test with the addition of walking around the bus listening for air leaks; of course, with the bus securely chocked to prevent rolling. Basically, chock the wheels, start the engine, build air pressure, wait for the air dryer to spit, turn off the engine, release the parking brakes, walk around listening for hissing sounds, come back inside and note the air gauge pressure loss which should be no more 2 psi in one minute.

How many of us do this pre-trip inspection test on every trip? A parking brake canister can have a slow leak such that it doesn't quite release and the brakes drag causing heat and a fire.