Positive Crankcase Ventilation: Description and Operation

Fig.3 - Positive Crankcase Ventilation (PCV) System:

Crankcase oil vapors are recirculated from the rocker arm cover to the intake manifold through two lines, Fig. 3. One line leads to the air cleaner side of the carburetor and the other line leads to the intake manifold side of the carburetor. One line is fitted with flame arrestor (B). This should be inspected and cleaned every 12,000 miles. The line leading to the intake manifold is fitted with a calibrated orifice (A) and should be cleaned every 12,000 miles.