Vacuum Delay Valve

Connect a hand vacuum pump to the VDV as shown in Fig. 2 and pump.







1. Valves with one side black or white and the other side colored are good if vacuum can be built-up in one direction, but not the other direction and if that built-up vacuum can be seen to slowly decrease.

2. Valves with both sides the same color are good if vacuum can be built-up in both directions before visibly decreasing.

NOTE: Exorcise care in order to prevent oil or dirt from getting into the valve.