Air Control Valve A

Fig. 43 Applying Vacuum To Air Control Valve 'A':

1. Disconnect the #16 hose from air control valve A and connect a vacuum pump to the hose, Fig. 43.
2. Pinch the upper large hose closed.
3. Disconnect the lower hose from air control valve A and connect a vacuum pump to the hose. Apply vacuum to the lower hose. There should be a restricted leak.
4. Release the upper large hose.
5. Apply vacuum to the #16 hose. The lower hose should now hold no vacuum (an unrestricted leak).
6. If the valve fails either test, replace the valve and re-test.