Releasing Spring Brake Manually - Blue Bird D3RE 2014 Driver's Handbook Manual

Releasing Spring Brake Manually

When air pressure fails in the rear service brake chamber, the power spring applies
the rear service brakes. Unless pressure can be re-established, the park brakes must
be released, as follows, to move the bus.
[WARNING] Do not release the spring brake until the bus is secured by wheel
chocks or tow vehicle. Failure to do so may result in bodily injury or property
damage.
1. Remove the release stud tool and nut from the carrying pocket on the brake
chamber assembly.
2. Remove the access plug from the end of the spring chamber.
3. Insert the release stud through the opening in the chamber and into the
spring pressure plate.
4. Turn the release stud one quarter turn to engage the stud tangs with the slot
in the pressure plate.
5. Keep the stud engaged and install the nut on the release stud.
6. Tighten the nut until the spring is fully caged and the brakes are released.
7. Do not loosen or remove the release stud and nut unless the brake chamber
is completely assembled and is securely clamped.
8. When air pressure is restored, remove the release stud and install in carrying
pocket.
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DRIVER'S HANDBOOK