Air Injection Check Valve: Testing and Inspection

Inspect:
1. A check valve should be inspected whenever the hose is disconnected from it or whenever check valve failure is suspected (a pump that has become inoperative and has shown indications of having exhaust gases in the pump would indicate check valve failure).

2. Remove the check valve.

3. Blow through the check valve toward the exhaust manifold side. Air should pass freely. Turn the valve around and attempt to blow through the valve toward the AIR pump side. No air should pass through the valve.

4. Replace valve which does not operate properly.