Replacing the rear main seal in a 360 without removing the crank?

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Litz

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Can you guys give me some tips on replacing the rear main seal on my 360 without removing the crankshaft? I've heard it can be done but I would like some tips from you guys that have done it before so I don't ruin the new seal. I haven't removed the old seal from the main cap yet but it doesn't appear to look like the same material as the new one. Also there is a small plastic tool in the new pkg. for installation of the new seal and I'm not sure how to use it. (Sorry for my ignorance.) Thanks in advance.
 
here is a video I just made a few weeks ago for this site ..
 
here is a video I just made a few weeks ago for this site ..

Thanks for the reply and great video. My new seal is not of the felt type but rather a black neoprene I imagine that I should lube the seal and work it around the crankshaft until it's flush with the block. Should I put rtv, or sealer where the 2 halves meet or will it seal without using anything? I hate oil leaks! Thanks for your reply/patience. (First timer here and I don't want to screw anything up)
 
Thanks for the reply and great video. My new seal is not of the felt type but rather a black neoprene I imagine that I should lube the seal and work it around the crankshaft until it's flush with the block. Should I put rtv, or sealer where the 2 halves meet or will it seal without using anything? I hate oil leaks! Thanks for your reply/patience. (First timer here and I don't want to screw anything up)
yes, you'll use a little rtv at the ends, I just do the block side. I put a little oil on the new seals inner lip. I use the fel pro seals (hard rubber).
 
Thanks for the reply and great video. My new seal is not of the felt type but rather a black neoprene I imagine that I should lube the seal and work it around the crankshaft until it's flush with the block. Should I put rtv, or sealer where the 2 halves meet or will it seal without using anything? I hate oil leaks! Thanks for your reply/patience. (First timer here and I don't want to screw anything up)

That's the basics right there, and the plastic is a "shoehorn" to keep from shaving the lip off the seal against the sharp edge of the block metal going in.
If you don't have the old one out of the block yet you need to come up with something that you can knock the seal loose and start it out where you can get to it with needle nose pliers or the like.
I like a 1/8 shaft Phillips screwdriver ground flat on the end, but a small flat nose punch will work if you are carefull about the crank surface.
RULE 1. Do not nick up the sealing surface on the crank getting that seal half loose and out.

Going in with the new one I don't use the little plastic "shoehorn" but lube it up like you said and ease it in there making sure it isn't getting trimmed by the block until the end still sticks out about 1/4 inch.
Put the main cap half in with the other end sticking up just a bit so the seal tips are both offset a little from the main cap surface to block seam.
This helps to insure that the seams of the seal are for sure fully supported.
Wipe the ends of the new seal pretty good to get the lube off and dab about 1/8 dab of RTV on the tips of the seal and get her together.

There are mixed opinions on putting a super small thin film of RTV between the cap and the block from the seal end groove to the edge of the main cap seating surface and up the side to keep oil from getting out between the main cap and block, but that is a choice you will have to decide I guess. (I always do it because leaks suck)

Oh, and be sure to put the seal facing the right direction. :D
 
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