57 fleetwood rear main seal is turning into a nightmare Please Help

[Saw92345]

So i have tried the rope seal with the sneaky pete tool and still had a little bit of a drip, went to the local auto parts store here in So.Cali. and they sold me a rubber seal from felpro, didn`t work because it was the wrong one, went to another auto parts store, they sold me one that didn't fit. Got one through Caddy Daddy (the latest one) part #3767 made by Best Gasket. It fit in the grove of the main bearing cap perfectly, it was the right length , when I went to install the upper part on the motor it fit in so easily i had my doubts that it could seal. it seemed like it was to big around the crank shaft. Got it back together and sure enough it was a pretty bad leak, can someone help me and tell me what I am doing wrong or give me any direction at all. this was all something I wanted to have done by Fathers day for my dad but that day has come and gone and it is still dragging on. Yesterday I tried going back to the rope seal but busted all the clamps that came with the sneaky Pete tool I had just bought and still couldn`t get the rope seal in. Thanks for reading my post and for any help the community can give me.

[gary griffin]

I have used Sneaky Pete a few times and always with good results.  Did you loosen the crankshaft bolts letting the crank shaft lower it self with gravity. A couple full turns of the bolts should be enough. The fact that you broke Sneaky makes me think you may not have done that? The seal may look a little too big but it is compressed when you re-tighten the bearing cap bolts.  Push on the opposite end of  the seal while pulling the Sneaky Pete.  Also use a light oil such as 10Wvto lubricate the sneaky Pete.  Been a while but went well every time!!

[V63]

Your best chances of success are with the lip seal*

Make sure the ‘lip’ seal is facing the proper direction! It should be facing into the engine.

Verify too that you are in the proper groove. Refer to shop manual image.

The seams of the seal and the main bearing cap should NOT all line up...push one end of 1/2 of seal arc into the engine groove about 1/4 inch. This will of coarse make the corresponding, opposite side, protrude the same amount. Install cap seal arc similarly.

If memory serves, I recollect the instructions for best seal advise ‘use no sealer’ ? ...refer to instructions on that.

Verify that your engine is not a later 1958 and up...that is a different seal, not a rope seal design. it is the first factory lip seal offering. 

* Their website does suggest that ‘due to machining variances...seal performance may vary’.*  👇

You might want to mic your crank diameter at the seal contact...call best tech support to see if your diameter is within lip seal working range?

if this is the case ...you are forced to use their rope seal option. I would use only their brand of rope seal as most other modern replacements (all?) are inadequate in both materials and sizing.

[Saw92345]

thanks for the information and I will bring a mic home with me tomorrow and check it and get a hold of the tech support and see if we are in range  and go from there.

[novetti]

The area where the seal touches the crankshaft has a fine knurl pattern. Clean it properly. Spin the crank a few times to check the whole perimeter.
Its common to find some some rust/corrosion there.