Air Injection: Testing and Inspection

Air Management Valve:

AIR MANAGEMENT VALVE TESTING

1. With engine idling at normal operating temperature, ensure secondary air is passing from silencer on air management valve (AMV).
2. Stop engine. Disconnect air hose at check valve and plug opening of check valve. Start engine and note that air passes from AMV for a few seconds. After a few seconds air should pass from the silencer. Replace AMV if defective.

AIR INJECTION PUMP INSPECTION

Check the air pump for abnormal noise or broken components and replace if found defective. The pump is not serviceable and must be replaced as a unit.

Check Valve:

CHECK VALVE TESTING

Remove check valve from the air manifold. Test for leakage by blowing air into the valve from the air pump side and from the air manifold side. A good valve will only pass air from the pump side. The valve is defective if air passes from the manifold side and should be replaced. A small amount of air leakage may be overlooked.

AIR HOSE AND INJECTION PIPE INSPECTION

Check around the air manifold for air leakage with the engine running at 2000 rpm. If air is leaking from the nozzle sleeve nuts, tighten them.
Check and replace hoses if found to be fatigued or cracked. Also check hose joints and clamps. Be sure hoses are not rubbing against adjacent components.