Crankcase ventilation system (with carburetor)
1 – control valve, 2 – separator, 3 – filter in the oil cap
Crankcase ventilation system (with fuel injection system)

Engine Crankcase Ventilation System Valve
A – full opening, B – partial opening. 1 – body, 2 – spring, 3 – piston, 4 – washer, 5 – stopper
Through the oil separator 2 with the adjustable valve 1, the crankcase gases are discharged into the intake manifold (see Fig. Crankcase ventilation system (with carburetor)). Crankcase ventilation depends on the flow of air sucked in by the running engine. The adjustment valve, as well as the filter in the oil plug, must be washed in fuel every 20,000 km. The valve must be replaced every 40,000 km.
(The material was copied from an information website: www.FordBook.ru)