Crankcase Ventilation Systems: Operation

Air enters system through air cleaner, to a filter element (1968-74) or a mesh breather assembly (1965-67), through a hose, and into rocker arm cover. Ventilation fumes are picked up at rocker cover and routed through a hose and PCV valve to intake manifold. Here fumes are mixed with air/fuel mixture and burned in combustion chambers. PCV valve regulates flow of fumes to intake manifold by use of manifold vacuum.