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Closed-circuit crankcase ventilation

Closed-circuit crankcase ventilation

The engine's crankcase has closed-circuit ventilation consisting of a positive crankcase ventilation (PCV) nipple on the camshaft cover from which two hoses lead to the throttle body.


The hoses and their connections are dimensioned to provide sufficient evacuation of crankcase gases from the engine under all operational conditions.


The crankcase gases are evacuated via the (PCV) nipple on the camshaft cover through one small-bore and one large-bore hose to the throttle body, where the gases are mixed with the intake air and burned in the engine. When the engine is running on low or medium-high loads, the crankcase gases are led to the throttle body through the small-bore hose which is connected to the throttle.


There is a non- return valve on the small-bore hose on the turbo engine, which prevents the over- pressure from reaching the crankcase. At full load the crankcase gases are evacuated through the large-bore hose which is connected in front of the butterfly. On the turbo engines this large-bore hose is a pipe, which is connected to the turbo charger's intake pipe.