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Crankcase Ventilation

Fig 1: Identifying Crankcase Ventilation
GLL154241Courtesy of VOLVO CARS CORPORATION

The system is pressure controlled and completely enclosed.

Crankcase gases flow up to both the valve covers. There is a hose connecting the valve covers. A labyrinth system of plates is installed in the valve covers. The oil in the gases condenses on the plates and drains back to the oil pan.

The ventilation is pressure controlled to retain stable pressure in the crankcase. A pressure regulator is installed on the rear edge of the right valve cover. The gases which are evacuated are led from the regulator through a hose to a connection on the inlet pipe. Coolant is circulated around the connection to prevent freezing.

The pressure in the crankcase is approximately - 0.03 bar.