Air Brake Quick Release Valve Leakage Test for GMC Truck TopKick C-Series (Crew) C6/C7/C8 2003
- Block the wheels.
- Apply the parking brake.
- Start the engine.
- Charge the system air pressure to the governor cut-out point.
- Have an assistant apply the brake pedal.
- Coat the exhaust port (5) with
a soap solution.
- Check that leakage is less than a 25 mm (1 in) bubble
in three seconds.
- Replace or overhaul the valve (1) if the leakage exceeds
these specifications. Refer to
Air Brake Quick Release Valve Replacement
or
Air Brake System Description and Operation
.
- Coat the cover and the mating area between the top and the bottom
of the valve (4) with a soap solution.
- Check for leakage.
- If any bubbles appear, replace or overhaul the valve (4).
Refer to
Air Brake Quick Release Valve Replacement
or
Air Brake System Description and Operation
.
- Remove the wheel blocks.