Repair Topics / Engine Seals

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MORE: Engine seal questions

Question: 1999 Ford Thunderbird mileage: 105,000.  I have an oil leak that is [I believe] the rear main seal.  Does the engine have to be removed to replace the seal or can it be replaced by removing the transmission?

Answer:  You can replace the rear main seal by removing either.  However, the transmission is a lot easier to remove than the engine.

Question: 1993 Mercury Tracer, miles 121,000 Recently I had the head gasket replace and valves redone. The guys at the shop took about 4 weeks to do the repairs. I've had my car about two weeks now and the A/C compressor area started making a loud noise. The A/C was working then stopped when the noise started. I looked at the compressor and I think (hope) it may be the clutch. It has a little grease leaking in the front on the clutch. The guy at the shop is saying the grease is from the compressor. I really don't know. In addition, if I replace the clutch will I need to decompress the system or is the clutch a separate piece? Also, Is there any chance the guys at the shop could have done something to cause this? I've found many many screws missing on my car. I would prefer to do the work myself. Thank you for your site.

Answer: Your problem is unfortunately, not the compressor clutch. It sounds like a bearing failure, which would cause the seal to break down thereby leaking oil onto the clutch. The compressor must be replaced. This requires special equipment to retrieve the Freon. As for your question regarding "the guys at the shop" causing this problem, I am sure you can understand it is difficult from this distance to judge someone else’s work.

Question: 1989 Ford Mustang, miles: 100,200  A bad oil leak at rear of engine. My Chilton’s book shows the rear main seal as being two-piece that fits in rear main. The parts store sold me a one-piece seal. I would like to know which it is before I go to the trouble of tearing down for one type and it turn out to be the other type.

Answer: Your engine should be equipped with a one-piece rear main seal.

Repair Topics / Engine Seals