Positive Crankcase Ventilation: Description and Operation

The engine has a fully enclosed crankcase ventilation system. The crankcase gasses are evacuated via passages in the cylinder block, through a crankcase ventilation housing mounted on the cylinder block, through a small-bore and a large-bore hose to the throttle body where the gasses are mixed with intake air and are combusted in the engine.

When the engine is at idling speed, the crankcase gasses are channeled through the small-bore hose and when there is load on the engine, through the large-bore hose. The hoses and their connections are sized to give satisfactory evacuation of the crankcase gasses from the engine under all operating conditions.

To avoid icing, the system is water heated.