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| | | | Joined: Oct 2006 Posts: 117 Shop Shark | | Shop Shark Joined: Oct 2006 Posts: 117 | So my situation is I have a totally rebuilt 59 235 car motor that has the 2 pc neoprene rear main seal replaced twice and still leaks, bad. I'm talking a quart every 200 miles or so. Strange thing is it never leaked prior to the rebuild and had the same type seal.
This motor did get a reman crank (.020 mains and .010 rods) and I am wondering if enough material was removed/polished off of the seal surface to affect the neoprene seals ability to seal.
I am going to try a rope seal this weekend as some of the searches I found indicated that some of you all have had better luck with and felt the rope seal was a better option.
One further question, should the rope seal be soaked in motor oil prior to installation or just put in out of the package?
Any suggestions? Experiences?
Thanks,
Chuck | | | | | Joined: Aug 2012 Posts: 566 Shop Shark | | Shop Shark Joined: Aug 2012 Posts: 566 | I would try a rope seal with the asbestos from NOS like the original. This week end i am going to try it.
"As I lay rubber down the street, I pray for traction I can keep, but if I spin and begin to slide, please dear God protect my sweet ride." -Amen 56 Chevy 3100 | | | | | Joined: Oct 2006 Posts: 1,847 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 1,847 | NOS isn't a place it, means new old stock. leftovers from when they actally made them. (unless you are dealing with nitrous, then it is a brand name) I'm not sure exactly when they stopped making asbestos seals, but I'm thinking mid 70's(?) The absolute best way to go if you had the engine apart is the full circle seal, but it doesn't sound like you really have that option. Just keep it in mind when, and if you build another one of these engines. | | | | | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 | If your engine is machined to take a neoprene seal (which
your '59 is) then consider yourself lucky. That is a much
better seal than the rope seals were or are now. They are a
contant problem and leak 98% of the time even when properly
installed.
.020" off the rear main bearing surface is nothing to be
concerned about, that only amounts to .010" at the sealing
edge. A neoprene seal is much more tolerent than that.
I would suspect that the seal is not being installed properly or
is being damaged when it's installed.
Denny Graham
Sandwich, IL
Denny G
Sandwich, IL
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | I would look at the clearance on the main bearings, especially the rear. I know it is a rebuild but too much clearance will cause a leak. | | |
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