- Block the wheels.
Notice: Do not apply the brake pedal while the balance port air line is disconnected.
Damage to the slack adjuster can result.
- Disconnect the balance port air line.
- Start the engine.
- Charge the system air pressure to the governor cut-out point.
- Apply the system park control.
- Apply a soap solution to the exhaust port and the balance port (2).
- Check that leakage is less than a 25 mm (1 in) bubble
in 3 seconds.
- Repair or replace the valve (3).
- Apply a soap solution around the cap nut at the control port (9)
and at the seam between the cover and the valve body. Leakage is not permissible.
- Pull out the system park control.
- Connect the balance port (2) to the air line.
- Disconnect the control port (9) to the air line.
- Apply the brake pedal hard.
- Apply a soap solution to the control port, the exhaust port, and
the area around the exhaust port (retaining ring).
- Check that the leakage is less than a 25 mm (1 in)
bubble in 3 seconds.
- Replace the valve (3).
- Connect the control port air line.
- Check for leaks in the air lines.
- Remove the wheel blocks.