replacing main cap side seals in car ?

[cozye]

After replacing my rear main seal twice, and replacing my oil pan gasket. I still have the same small oil leak on the back of the block. I believe the only thing left that it could be is the side seals. The 2nd rear main seal I pulled out had no visible issues, and the 2nd one I put in I was very careful to make sure it had no burs and went in correctly.

I saw the two side seals on the rear cap when I replaced the oil pan gasket, I guess my question is can they be removed easily and replaced once the oil pan is off? The FSM shows installing the side seals on a motor rebuild, but I've not seen any decent "replacement" procedure.

[Diseazd]

Without a ST to remove the rear main bearing cap, it would be a bitch. The rear main cap is a super tight press fit.

[gryt57]

You should be able to pull the side seals and the nails without pulling the rear main cap. Probably take a little prying to dig them out, but I think it can be done.

[cozye]

whats an ST ?

gyrt57, I've seen the side seals in there, I think they are the type without the metal shims, and there isn't anything sticking out to grab a hold of.

Sounds like I may just have to live with this oil leak.

[zKars]

Nothing is impossible, just different levels of challenge. There is a 6 or 8mm threaded hole in the center of the cap for the "special tool" to thread into. Now let your imagination help you design a tool that can apply leverage to pull the cap straight out. Maybe even a simple hammer. Piece of 6mm threaded rod, washwr, nut, well you get the idea. Good luck!

[gryt57]

I thought if you could somehow grab one of the nails or expanders pull that out, the side seals would slide out. When I put mine in, the seals were so tight I could not put in the nails. How about a bead of silicone along the two cracks between the block and main cap? Maybe worth a try.

[Diseazd]

Sorry....ST is special tool.......there's a picture in the Service Manual(FSM) that shows one. By the way, your chances of prying out those side seals without removing the bearing cap are about the same chances of me winning Indy this year with my Z. Also, I'll bet you can't find anyone on this forum that has ever replaced the side seals while in the car. Finally, I'll also bet that side seals are not your problem......there is absolutely nothing to wear out or deteriorate with a side seal. They just don't go bad......Ever. All IMO.

Edited March 28, 2011 by Diseazd

[cozye]

Sorry....ST is special tool.......there's a picture in the Service Manual(FSM) that shows one. By the way, your chances of prying out those side seals without removing the bearing cap are about the same chances of me winning Indy this year with my Z. Also, I'll bet you can't find anyone on this forum that has ever replaced the side seals while in the car. Finally, I'll also bet that side seals are not your problem......there is absolutely nothing to wear out or deteriorate with a side seal. They just don't go bad......Ever. All IMO.

That may be true. I'm just not seeing how the rear main could be such a PITA. Both times I have replaced it, it made absolutely no difference. It shouldn't be that difficult to repair a rear main, and all of the previous advice I've received and the research that I've done shows that people generally don't have issues replacing it. I'm pretty good with a wrench, and I was especially careful about it the 2nd time around.

[cozye]

I should also add that once, while troubleshooting and trying to find vacuum leaks, I had the PVC and crank case breather hose clamped off while the motor was running. It was a dumb move, but positive pressure built up in the crank case and shot the dipstick out after about a minute of running. I thought that possibly this would be how the side seals may have developed a leak.

Also worth mentioning is the fact that there wasn't any leak prior to me replacing the rear main seal when doing the clutch last fall as preventative maintenance. It all started after I replaced it the first time. The 2nd time I replaced it I used a different brand seal to be sure.

[clayton 260z]

I have had the same annoying oil leak in my car also. I had replaced the rear main two times with no luck it still leaked. What I thought was the rear main seal leaking was the side seal.

With no special tools we fixed the problem, pulled transmission, loosen motor mounts removed oil pan, removed rear crank cap carefully, removed old side seals from cap, replaced cap torqued to 40 lbs then replaced side seals, new rear main seal and put everthing back.

It was not hard just took time. The best thing no more oil leak.

Now why did the the side seals leak? We rebuilt the motor a little over four years ago and I am quite sure they were not replaced then and the old ones were left in somehow. This is just a guess do to the condition of the seals when removed, a little hard and appeared to be much older than they should have looked.

It can be done......

[cozye]

I have had the same annoying oil leak in my car also. I had replaced the rear main two times with no luck it still leaked. What I thought was the rear main seal leaking was the side seal.

With no special tools we fixed the problem, pulled transmission, loosen motor mounts removed oil pan, removed rear crank cap carefully, removed old side seals from cap, replaced cap torqued to 40 lbs then replaced side seals, new rear main seal and put everthing back.

It was not hard just took time. The best thing no more oil leak.

Now why did the the side seals leak? We rebuilt the motor a little over four years ago and I am quite sure they were not replaced then and the old ones were left in somehow. This is just a guess do to the condition of the seals when removed, a little hard and appeared to be much older than they should have looked.

It can be done......

Interesting. Any reason why you removed the tranny and motor mounts? I can easily get the oil pan off without doing either, so I'm wondering if I do attempt this if I can get away without those steps. I can get the oil pan off in less than an hour. From the looks of it, it looked like the rear main cap would lift straight off as well, without the need to redo the rear main seal ?

[clayton 260z]

I run an Arizona Z aluminum pan and the pick up is hard to line up and drop into place with out the motor up about 1 inch. Removed tranny to put another seal in, did not remove motor mounts just loosened to be able to lift motor enough to remove pan. The pan will hit the crank if you don't turn it as you remove the pan, lifting just made it easier.

Again all was removed just to be on the safe side. The cap came off fairly easy with a little tap do not mess with the bearing.

Good Luck