Air Control Valve B: Prelude
- Disconnect the top hose from air control valve B. Connect a vacuum pump and apply vacuum. Disconnect air hose from vacuum hose manifold. See Figure . Ensure air will pass through valve.
- Release vacuum. Check that air will pass through, even though some resistance may be felt. If air control valve tests as described, valve is okay. If there is no change in resistance, replace valve and retest.