Positive Crankcase Ventilation: Testing and Inspection

WARNING: Operating an engine without an effective crankcase ventilation system may damage the engine. Replace the Positive Crankcase Ventilation (PCV) valve at regular intervals. Use the correct PCV valve for the engine and equipment type. Wrong or substandard parts may damage the engine components.

Procedure
Use the following procedure to check the function of the PCV system:

1. Start the engine.
2. Run the engine at idle.




3. Place your thumb over the end of the PCV valve (1) to check for vacuum. Check for a plugged intake manifold port, PCV valve or vacuum hoses, if there is no vacuum at the PCV valve. Replace or repair as necessary.
4. Turn OFF the ignition.
5. Remove the PCV valve.




6. Shake the PCV valve while listening for the rattle of the needle inside. Replace the PCV valve if the valve does not rattle.

NOTES
^ Proper operation of the PCV system is dependent upon a sealed engine. Check that the PCV system is functioning properly, if the build up of oil sludge or oil dilution is found. Check the engine for possible causes and correct, in order to ensure that the system will function as intended.

^ Periodically inspect the hoses and clamps in the PCV system. Replace any components showing signs of damage or deterioration. Check for a clogged PCV valve or a plugged hose if the engine is idling rough.