Leak Identification

Front Cover O-ring Seal

Inspect the mating surface between the cylinder block and the front cover in the area of the O-ring seal. The seal is located between the 2nd and 3rd bolts up from the bottom edge of the front cover on the rear side. If oily deposits are present, the area should be cleaned thoroughly before inspection in order to isolate the origin of the leak. With the engine running, you will be able to see oil seeping from this area. Be sure the oil is coming from this area before proceeding with the O-ring seal replacement.

Oil separator assembly

If oil seepage from the O-ring is not observed in the above inspection the oil separator should be cleaned and inspected. The oil separator assembly is bolted to the front cover on the rear side above the power steering pump, close to the O-ring seal. Because it is difficult to see, a leak from this component is sometime misdiagnosed as a leaking O-ring seal. Oil may not leak from this component while the engine is running, but leak after the engine is shut off. Carefully inspect this component if oil appears to be leaking from the O-ring seal.

Oil pan

If the oil pan leaks from the joint at the front cover, it may appear to be the front cover that is leaking. If there is no oil along the front cover/cylinder block mating surface just below the O-ring area, then the oil pan may be the origin of the leak. As with the oil separator assembly, oil may not leak from this component while the engine is running, but it may leak after the engine is shut off. It may be useful to use a dye visible under black light to help isolate the exact origin of an oil leak from the oil pan.

Crankshaft front oil seal

A leaking crankshaft front oil seal usually causes oil to leak onto the backside of the crankshaft pulley, from where it is thrown off onto all surrounding components. The back side of the crankshaft pulley will probably be wet with oil. This component may leak due to excessive crankcase pressure caused by a clogged or stuck PCV valve.