GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 2002 🢒 Isuzu T-Series (Truck Line C) 🢒 Brakes 🢒 Air Compressor 🢒 Air Compressor Governor Valve Adjustment

You may need to adjust the governor under the following conditions:

    • The range falls below 100 kPa (15 psi) of the recommended pressures.
    • The pressure settings are incorrect.

Before you make any adjustments, check the engine air filter element and the governor air inlet hose for restrictions using the following procedure:


    Object Number: 200542 Size: SH
  1. Remove the top cover from the governor.

    2. Object Number: 230291 Size: SH
  2. Loosen the adjusting screw locknut.

    3. Important: Do not over adjust the adjusting screw. Each 1/4 turn of the adjusting screw locknut raises or lowers the pressure settings approximately 28 kPa (4 psi).

    • The pressure range between the cut-in and the cut-out setting is not adjustable.
    • In order to raise the pressure setting, turn the adjusting screw counter-clockwise. In order to lower the pressure setting, turn the adjusting screw clockwise.
    • After you make the adjustment, tighten the adjusting screw locknut.
    • Recheck the cut-in and the cut-out pressures.
    • Install the cover on the governor. Refer to Air Compressor Governor Valve Specifications for the correct governor settings.