Rear seal question

DWester

Member
While assembling my motor, I've read that it's a good idea to soak the rear seal in oil for at least 1/2 hour prior to installing it. When I opened the gasket set, I noticed that the seal was coated in something white and don't remember seeing them done like that before. Anyway, I followed instructions and soaked it. Will this be OK?
 
Hard to say if it works at this point. I'd just as soon leave it alone, but if there's any concern of the oil compromising the integrity of the seal, I'll replace it. There's no rods connected yet.
 
If it's the original rope type seal, I have always been told you should soak it so that it will compress more tightly when bearing cap and crank is installed. This "compacting" makes seal porus and therefore less prone to leak. Trimming to correct length also matters. If it's a rubber style seal, perhaps the white stuff is residual mold release talc.No knowledge of that.

Here's a more complete answer from Rodnut back ion 2001.

http://www.btc-bci.com/~billben/mainseal.htm
 
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I do soak the seals you are talking about. The only ones I don't are the Best Gasket black ones. They say not to. Have had good luck with both. Always wind up with a small seep somewhere along the line, but, no "leak". I've been told for years that they only make 2 different types of rope seals - "Those that leak and those that are going to."
 
I keep a can of oil in my tool box with a pair of rope seals inside, and swap them for a new set when I use the soaked pair. The white coating is probably white lead for lube. The usual reason for leaking ropes is that the ends were cut when installed. They must be left long so the cap forces them to bulge as it is tightened. A dab of sealer on the ends is a good idea, as well. If excess seepage occurs, it is likely the surface of the crank was uneven or scored.
 
The best rear seal is Best Gasket Co. if you use one you'll never go back to those white one or the black ones that cain't cut with a razor blade. Walt
 
I always thought the white FelPro seals were teflon-coated, but it turns out they are just color-coded -- see pic
 

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