Gaskets and Sealing
Gaskets and seals are usually named after their location or function on the engine. For example, a head gasket seals the cylinder head to the cylinder block. A rear main seal prevents the area around the rear crankshaft main bearing from leaking oil. Gaskets and seals can be made from a wide range of materials, many times specifically selected for the specific sealing task.
Engine seals and gaskets prevent the leakage of oil, coolant and air between mating surfaces, internal passages and the outside of the engine. Seals and gaskets also prevent the entry of dirt and air into the engine.
The best way to care for the gaskets and seals on your engine is to follow a regular maintenance regimen. This includes regular oil and filter changes, engine performance check-ups, and cooling system maintenance. Check your owner's manual for positive crankcase ventilation (PCV) maintenance intervals and replace the valve as recommended. Oil leaks are one clue of a faulty PCV system. Leaking valve cover gaskets and rear main seals are but a few examples. If the PCV system isn't operating correctly, crankcase pressure can build and force oil past gaskets and seals that would have otherwise been OK. Overheating can quickly cause head gasket failure and warp aluminium cylinder heads. If telltale oil or coolant drips in your driveway or parking place are making you suspicious about a gasket or seal leak, have it investigated by a qualified service technician.