REMOVAL & INSTALLATION
See Figure 1
- Disconnect the negative battery cable.
- Remove the vacuum hose from the dump valve.
- Remove the dump valve from the bracket.
- Install the valve to the bracket.
- Connect the vacuum hose.
- Adjust vacuum dump valve. For details, please refer to the adjustment procedure located later in this section.
- Connect the negative battery cable.
Adjust the vacuum dump valve so that it is closed (no vacuum leak) when the brake pedal is up (brakes released) and open when the pedal is depressed.
The vacuum dump valve releases vacuum in the servo assembly whenever the brake pedal is depressed and thus acts as a redundant safety feature. The vacuum dump valve should be checked whenever brake application does not disconnect the speed control system.
- Disconnect vacuum hose with the white stripe from the dump valve. Connect a vacuum pump to hose and apply vacuum.
- If a vacuum cannot be obtained, hose or dump valve is leaking. Replace or repair defective components as required.
- Step on the brake pedal, vacuum should be released. If not, adjust or replace dump valve.
- The dump valve black housing must clear white plastic pad on brake pedal by 0.05-0.10 in. (1.3-2.5mm) with the brake pedal pulled to rearmost position.