455 olds main seal

[jungledave]

Anyone out there an expert on installing a rope ear main seal on an olds 455? I put in a new rubber seal last summer and it leaks, It looks identical to the 460 seal someone else on here said works. I don't own a sneaky pete main seal installer. I am replacing the mains so I can lift the crank a little. How much of the rope do you leave on each half?

[058]

Rope seals are best installed with the crank completely removed so that they may be packed. A properly installed rope seal should be so tight that you need a wrench to turn the crank when first installed. The 460 Ford seal should work for you without problems. Don't know much about Olds mains as its been many years since I built an Olds but if they are anything like the Ford that used a rope seal there would be a small pointed dowel in the cap or the block that holds the rope in place. This dowel needs to be removed in order for the neoprene seal to seat properly. A very thin layer of high temp. silicone between the block and cap helps to seal the rear main to keep it from weeping. Also be sure you have the neoprene seal installed correctly, the lip should go towards the inside of the engine and the seal should be pre-lubed upon installation, dry starts can destroy the seal lip..

[malcolm]

I'd do a little checking as to why the rubber seal is leaking. You won't be happy with the rope type. I like to turn them just a bit (maybe a 1/4") so the halves aren't quite even with the cap/block. That way the seams aren't all lined up.
I'm guessing a rope seal in a boat engine won't last long at all. :idea:

[oldselmn8tr]

Also a good idea if switching from a rope type seal to neoprene is to polish the crank where the seal rides.

[jungledave]

I'd do a little checking as to why the rubber seal is leaking. You won't be happy with the rope type. I like to turn them just a bit (maybe a 1/4") so the halves aren't quite even with the cap/block. That way the seams aren't all lined up.
I'm guessing a rope seal in a boat engine won't last long at all. :idea:I removed the original rope seal out of the engine last august 06. The engine has 700 hours on it and is still in great shape. The 75 low compression 455 never made enough power to hurt itself. The seal was shot. I correctly installed the new seal. It was a felpro boxed rubber rear main for an olds 455. It is identical to the 460 seal I ordered. It worked most of the summer, than just started leaking. I pulled the motor tilted it up and added 4 extra quarts of tranny fluid and sure enough it weeped out of the main seal. I was wondering about the rope because I have an extra out of a gasket set.

[jungledave]

Also a good idea if switching from a rope type seal to neoprene is to polish the crank where the seal rides.I'll clean it up the best I can with the crank in it. I decided to try another neoprene seal. I looks like the neoprene seal doesn't have a big enough lip on it.