SYSTEMS
PCV VALVE & CRANKCASE FILTER
INSPECTING YOUR CRANKCASE FILTER
VARIATIONSCORRECT OPERATION
The PCV valve is the heart of a closed pollution control system that takes filtered air and directs it to the crankcase where it picks up vapors. These vapors are composed of blowby gases and unburned gases from fuel in the oil. The vapors are then pulled by engine vacuum through the PCV valve into the carburetor or throttle body for combustion in the cylinders. However, prior to being drawn from the crankcase, the vapors are mixed with air filtered by the crankcase filter. The PCV valve will work best when engine vacuum is greatest -- at low engine speed, idle, or deceleration.
SYSTEMS PCV VALVE & CRANKCASE FILTER INSPECTING YOUR CRANKCASE FILTER VARIATIONS