Oil leaks can be a real annoyance, there are so many gaskets on your engine to keep the seams sealed so oil cannot escape, but over time they can wear out, become brittle, and begin to leak. This gasket seals the crankcase breather to the engine block, underneath the intake manifold, to seal in crankcase pressure and stop oil from exiting through the breather. Keep your engine leak free by replacing a faulty seal or installing a new one with your new breather.