Positive Crankcase Ventilation: Description and Operation

Crankcase Ventilation System:

Valley Cover With Oil Vapor Maze:

The crankcase breather is located between the cylinder banks. The cover is opened on the bottom to crankcase vapors, these vapors are drawn through a maze of passages to help separate the finer drops of oil and prevent them from being drawn in by the engine. Fumes from the crankcase breather are drawn through a restrictor at the back of the intake manifold during idle. When the throttle is opened, additional ventilation takes place through the large hose connected at the front of the breather to the throttle housing.