BAFFLES FOR THE 318 VALVE COVERS - OIL LEAK

On a correctly functioning PCV system, the breather lets fresh air in to the system when vacuum is high, light throttle/load situations. When vacuum is low (0) under hard acceleration high load situations, the breather let’s combustion gasses that push past the rings and in to the crankcase, escape. The breather works both ways. A good baffle is almost necessary in any valve cover hole that isn’t a sealed cap.