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Another Rear Main Seal Thread

1969VAGTX

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Before I begin, I have read through a bunch of the threads here about replacing the rear main seal. I also watched @Beekeeper videos on YouTube. We are getting ready to try to address the rear main seal in my GTX once and for all. The catch is we are doing this with the engine in my car. So here are my options, please provide your recommendations.

The car currently has a billet retainer in the car. I suspect the problem may be related to what @Beekeeper discusses in his videos. I also purchased a Fast Fish retainer and seal. And we have secured an original retainer. I am leaning towards installing the Fast Fish since a number of guys at Carlisle recommended that route to fix the leak, but I am curious if anyone has actually installed that one piece seal effectively with the engine in the car? When we pull the billet retainer out, I will check the clearances to see if it needs to be machined along the lines of the video recommendations as well.

Given all of these factors would appreciate some recommendations. Thanks.
 
Before I begin, I have read through a bunch of the threads here about replacing the rear main seal. I also watched @Beekeeper videos on YouTube. We are getting ready to try to address the rear main seal in my GTX once and for all. The catch is we are doing this with the engine in my car. So here are my options, please provide your recommendations.

The car currently has a billet retainer in the car. I suspect the problem may be related to what @Beekeeper discusses in his videos. I also purchased a Fast Fish retainer and seal. And we have secured an original retainer. I am leaning towards installing the Fast Fish since a number of guys at Carlisle recommended that route to fix the leak, but I am curious if anyone has actually installed that one piece seal effectively with the engine in the car? When we pull the billet retainer out, I will check the clearances to see if it needs to be machined along the lines of the video recommendations as well.

Given all of these factors would appreciate some recommendations. Thanks.
We’ve just fixed 2 rear main seals with the FastFish retainer. One was in the car and one was out of the car. I personally don’t like the one piece seal they use but their retainer is the best. We used a 2 piece fel-pro along with a fast fish retainer to fix my buddy’s roadrunner while the motor was in the car. I tried the fast fish one piece seal and a fel pro to fix mine but I guess I had too much of a clearance problem between the crank and the block. So I used an older felpro rope seal I had along with the FastFish retainer and it fixed it.
 
If you use stock retainer grind these nubs a little.
rear oil retainer.JPG
 
Ah, the dreaded rear main seal. I replaced on last summer on a 440 with a Mancini Racing retainer. I like the retainer better than the original as it has two rubber seals down each side. Having said that, I still have a leak. :mad:
 
I put mine together with a two piece Viton seal that I staggered the joint lines about 3/8" from
the joint line as others have suggested here on the forum. I can only hope that it doesn't leak when I fire it up!
Some people have suggested that the bore of the retainer is accentric to the crankshaft bores in
some cases, but not all. All I know is that I wish there were a fool proof way of fixing this problem
once and for all for everyone!
 
My last rear main seal debatable has hopefully come to an end with me hauling the motor to machine shop in northern MN. They weld up the crank in that area and turn it to Chevy size. Machine the block to fit the larger Chevy seal. I think they also have a custom retainer for this. You can imagine how fed up with my leak I must have been to go this route....
 
I'd be afraid to weld up the "business" end of a crank without a stress relieving cycle.
This problem has made alot of people go to extremes to fix the problem. I feel your pain!
 
FYI - I replaced my rear main seal 3 times only to find out it was 2-3 oil pan bolts bottomed out.... washers fixed it.
 
I believe I used a billet retainer from Hughes and a seal kit from Mancini on my Hemi - staggered the joint about 1/8”, sealed with anaerobic sealer on the seal connections, filled the bolt holes in the cap with RTV sealer, and tooled Right Stuff in the crevices behind the side seals. Hasn’t leaked any so far but now fighting a valve cover gasket.

edit: another thread reminded me I also put a very thin smear of RTV on the the retainer to block mating surface. Very important.
 
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I used a Indy Cylinder Head billet retainer kit in the 440 block in the 63 Fury and a rope seal with a stock retainer in the 400 block in the Roadrunner and no leaks on either.

Probably just jinxed myself!
Ruffcut
 
I used ARP Main studs on my 440 and those "Nibs" just barely kept the retainer from seating flat on the
mating surface. I'm not sure about stock main bolts?
 
Does the interfere or something?
They can, friend worked at a dealer he did engines. Put an engine together it leaked. Pulled the pan looked in at rear main cap saw retainer nubs touching main cap. Pulled retainer out ground nubs put it back in,fixed.
 
Many rear main seals replaced for no reason. Just because the leak is at the bottom it does not mean thats where the leak is.
 
Before I begin, I have read through a bunch of the threads here about replacing the rear main seal. I also watched @Beekeeper videos on YouTube. We are getting ready to try to address the rear main seal in my GTX once and for all. The catch is we are doing this with the engine in my car. So here are my options, please provide your recommendations.

The car currently has a billet retainer in the car. I suspect the problem may be related to what @Beekeeper discusses in his videos. I also purchased a Fast Fish retainer and seal. And we have secured an original retainer. I am leaning towards installing the Fast Fish since a number of guys at Carlisle recommended that route to fix the leak, but I am curious if anyone has actually installed that one piece seal effectively with the engine in the car? When we pull the billet retainer out, I will check the clearances to see if it needs to be machined along the lines of the video recommendations as well.

Given all of these factors would appreciate some recommendations. Thanks.
Rope seal for the win.
Before I begin, I have read through a bunch of the threads here about replacing the rear main seal. I also watched @Beekeeper videos on YouTube. We are getting ready to try to address the rear main seal in my GTX once and for all. The catch is we are doing this with the engine in my car. So here are my options, please provide your recommendations.

The car currently has a billet retainer in the car. I suspect the problem may be related to what @Beekeeper discusses in his videos. I also purchased a Fast Fish retainer and seal. And we have secured an original retainer. I am leaning towards installing the Fast Fish since a number of guys at Carlisle recommended that route to fix the leak, but I am curious if anyone has actually installed that one piece seal effectively with the engine in the car? When we pull the billet retainer out, I will check the clearances to see if it needs to be machined along the lines of the video recommendations as well.

Given all of these factors would appreciate some recommendations. Thanks.

Rope seal for the win. The issue I had with the rubber style seals leaking was with the crank shaft surface.
 
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Here’s the thing about a Fastfish retainer. For one its already made for engines that has ARP studs and what I like the best is it doesn’t use side seals and the outside edges are beveled so you can fill the bevel edges up with RTV. I do not like any of the retainers with side seals. If you have any clearance problems on the side they’ll leak. The one we fixed with the motor in the car was having side clearance problems from what we could tell. He had tried a Mancini and it still leaked. We didn’t try to offset the 2 piece seal or anything or sand it down for more crush. Got the first half of the seal in then put the seal in the FastFish retainer. Put just a smear of The Right Stuff on the ends, then on the sides of the retainers. Put some in the bolt holes and torqued it and filled the beveled edges up. Hasn’t leaked a drop since.
 
Update on this project: Installed the Fast Fish retainer. Also managed to work the one piece seal in to the groove. Keep in mind this was done with the engine in the car. Fast Fish seems to have a good fit in the block. Alas, after driving the car, the leak is still not gone. It might be marginally better than the sieve I had last summer, but it is still pushing oil out somewhere. Probably going to have to break down and do this the hard way - remove the engine form the car. That is a project that will have to now wait until next winter. In the meantime, anyone got any ideas with this little bit of knowledge of other things I should be looking for?

As an aside, there is no sign of oil anywhere around the block or heads. It is dripping straight out of the drip hole in the dust cover.
 
Oil always drips from the bottom. Most likely the rear intake manifold seal. Hard to see and many times overlooked.
 
Oil always drips from the bottom. Most likely the rear intake manifold seal. Hard to see and many times overlooked.
Yes, particularly with the oil pressure sender shield and the manifold heat pipes. But a strong shop light can be directed down the firewall and the area somewhat seen with the hood fully open. I can also snake my hand down there and work around the shield and pipes and run my fingers along the intake rear seal to see if I pick up any oil. Also the back rear corner of the valve covers can be hard to get sealed tight.
 
I’m fighting the same thing. Valve covers, oil sending unit, manifold, heads are all dry. I changed the rear main seal once and it made no difference. I’m wondering about the cam plug. Would like to pull the tranny and then run the engine to see if we can find the leak.
 
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