Club Cobra - Rear Main Seal Leak

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Rear Main Seal Leak

I dropped the pan, partially to replace the leaking rear main seal, the remainder to install my new Armando's oil pan. I discovered two interesting things when I looked at the rear main bearing cap: 1) there was a half section of a rear main seal (Ford part # - perhaps the original one) laying loose in the slot between the bearing and the seal groove; and 2) the upper portion of the Fel-Pro seal was installed backwards - with the lip facing out, rather than in. The half section in the bearing cap was installed correctly, however.

Whoever replaced the original seal must have been in a big hurry, oblivious or just sloppy.

Also, I realize the oil pan bolts are only torqued to 15 ft. lbs., but they seemed looser than that, and the rear main bearing bolts were suspiciously easy to remove as well - perhaps they didn't get the last pass when torquing in thirds.

I'm guessin it's probably a good idea to re torque all the caps, to be safe.

Quote:

Originally Posted by Tim7139 (Post 1350413)

I'm guessin it's probably a good idea to re torque all the caps, to be safe.

I backed them all off and started from scratch - 35/70/105 in the recommended sequence. S/b good now.

Sounds like you're good workmanship may have saved you a larger problem. When I discover something like that it throws the whole motor into question. How much history of the car do you have access to?

I would check with the seal manufacturer before you fit everything up.

Some seals do go in backwards. I've seen many now.

I would also like to kick the engine assembler in the backside, what else did he do inside?

Quote:

Originally Posted by keezling (Post 1350419)

Not enough. I remain in contact with the second owner, who I purchased the car from. He had the car for about 10 years and it sounds like most of the work during that period was done by someone other than himself, so he's of limited value on most of this stuff.

I do have contact information for the first owner and we had a good conversation last fall. For example, he was able to confirm the car had a hydraulic camshaft, while the lash was set as if it was a mechanical cam. He promised to send me an email with 'a million things' about the car, but he's an older gentleman and he hasn't been responding - so I'm a bit concerned about his health.

Quote:

Originally Posted by Gaz64 (Post 1350447)

The installed seal was a Fel-Pro with the same p/n as the one I purchased and installed. Instructions were very clear as to which way to install it - lip in. Regardless, the one I removed was lip out on the top half and lip in on the bottom half. Someone was snoozing that day.

It looks like the engine had the pistons replaced, perhaps about the time the engine was installed (1990-1991), as I believe the marks on the underside of the pistons (9-1548 IND BRAS M-2) aren't consistent with what Ford would have used in 1973. The pistons have also been drilled, presumably to balance them. I can also see honing marks on the lower cylinder walls - within the range traveled by the pistons.

I have not removed the heads to see the tops of the pistons, nor have I measured the cylinders to see if they've been bored. I am planning on purchasing an inspection camera to poke in the spark plug holes to see what's in there, though that obviously won't be as complete as pulling the heads - that will have to wait for later.

Surprised the camshaft has survived.

Hydraulic cam lobes (base circle) are ground differently to solid cams.