Description And Operation
The crankcase ventilation system channels vapors towards the separators, then the vapors are sent to the engine air intake system to be burned in the combustion chamber.
The system consists of the following components:
- (1) Left bank oil vapor separator
- (2) Right bank oil vapor separator
- (3) Connection pipe for the two separators
- (4) Inlet pipe for vapors to the bypass diaphragm
- (5) Diaphragm valve for bypass and maintaining vacuum in the block
- (6) Oil vapor outlet towards the left bank turbocharger air intake sleeve
- (7) Oil vapor outlet towards the left bank collector
The oil vapors are recirculated and sent exclusively to the left bank air intake system.
- (1) Oil vapor separator
The two engine banks collect the oil vapors and separate them from the suspended oil drops.
The right and left bank oil vapor separators move from their respective axis on the intake cams.
The oil vapors are collected in the separator by the vacuum created during the rotation of the separator. Once in the separator, the centrifugal force pushes the suspended oil droplets in towards the separator walls causing the droplets to separate from the vapors.
The vapors exit through the holes in the separators interior walls where they are routed along a pipe that will mix them with the vapors coming from the other bank. From there they are routed to the bypass diaphragm valve.
The valve diverts the vapor flow to the downstream environment, which is under vacuum at that time.
- (1) Oil vapor inlet from the separators
- (2) Outlet of oil vapors to the turbocharger intake
- (3) Outlet of oil vapor flow to the intake collector (after the throttle body)
Inside the valve there are diaphragms that are moved by the amount of vacuum inside the valve, thus controlling the direction of the flow of vapor.
- (2) Outlet hole diaphragm for oil vapors to the turbocharger
- (3) Outlet hole diaphragm for oil vapors to the intake collector
- (4) Upper diaphragm
The valve has two internal chambers. The first (upper) is the one that accepts the oil vapors coming from the separators. The second (lower) is the chamber that connects the two outlets (2) and (3). The upper and lower chambers are connected. The oil vapors coming into the upper chamber go to wards the lower one, but the passage is regulated by the diaphragm (4). The direction of flow out of the valve is determined by the amount of vacuum at the outlets (2) and (3). If for example, the engine is operating with the throttle body in a minimally closed position, the intake collector is in strong depression. This would cause the diaphragm at the intake collector (3) to open and the turbocharger diaphragm (2) to close, thus causing the oil vapor to travel into the intake collector (3).
If the engine is operating in full acceleration with the throttle open, the turbocharger is sucking in a lot of air, creating a vacuum in the air inlet sleeve. In these conditions, diaphragm (2) opens the passage and the diaphragm (3) closes at the same time. Moreover, diaphragm (4) prevents the engine block from experiencing excessive vacuum. If the block vacuum exceeds a certain threshold, it may allow oil to enter the air intake system.
The pipe connecting the valve to the intake sleeve that connects the turbocharger to the air filter box.