Figure 3.40. PCV system
1. The crankcase ventilation system removes unburned hydrocarbons (HC) into the atmosphere using a mixture of fresh exhaust air and oil vapor from the crankcase, directing them into the intake tract, where they are then burned.
2. The system requires a tight crankcase, it is necessary that the valve cover filler plug and the dipstick for measuring the oil level are tightly closed.
3. The system consists of a connecting hose from the air intake to the valve cover, an oil separator containing a steel orifice that collects oil droplets and drains them back into the pan, and a one-way PCV valve that is screwed into the intake manifold. The valve only allows gases to flow into the manifold, not in the opposite direction.
4. PCV filter is designed to separate dirt and other substances found in the crankcase to prevent contamination of the air filter element with oil.