Air Injection Pump: Testing and Inspection

1. Remove air cleaner, then inspect all hoses and hose connections for leaks. Correct as necessary. Check belt tension and correct as necessary.
2. With transmission in Park or Neutral and parking brake applied, start engine and allow it to reach normal operating temperature.
3. Stop engine. Disconnect air supply hose(s) from air pump to air by-pass valve from pump.
4. Install suitable thermactor test gauge in end of hose disconnected from by-pass valve. Secure hose with clamp to prevent it from blowing out. On side or cover mounted by-pass valves, install an elbow and hose adapter, then install test gauge. Position air pump supply tester so that air blast emitted will be harmlessly dissipated.
5. Connect tachometer to engine and start engine. Slowly increase engine speed to 1000 rpm while observing pressure at gauge. Air pump pressure should be at least 2.25 psi. If thermactor test gauge is not used, increase engine speed to 1500 rpm and place hand over open hose. Air flow should be heard and felt.
6. If air pump output pressure is not at least 2.25 psi, or if air flow is not heard and felt, replace pump and repeat test.