Positive Crankcase Ventilation: Description and Operation

PURPOSE
The crankcase emission controls prevent crankcase gases from being released into the atmosphere. Instead, the gases are routed to the intake manifold.

CONSTRUCTION
The system consists of an oil trap/seperator and breather hose. The oil trap/breather housing is attached and sealed to the side of the crankcase, it has a vapor inlet passage, an oil drain passage and a breather hose leading to the intake system.

OPERATION
Intake manifold vacuum draws the crankcase gases out of the crankcase into the intake system, where they are burned as part of the combustion process. The crankcase vapors get drawn through the oil trap and through the breather hose into the intake sysytem (upstream of the turbo).The trap uses a baffle system to separate the heavy oil particles from the vapors. The oil runs back into the crankcase through the exit at the bottom of the housing. The vapors exit at the top of the oil trap.