440 rear main seal... thoughts

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F/head,
Your post #48.

Sure is a looooooot of work!!!! So much of the time in this hobby is spent checking, checking, checking. Picking up the torque wrench is the last thing you do.

My experience is that aftermarket parts are very often poorly & inaccurately made. Rear main seal cover is a good example.....
 
The engine I just took out I put together years ago. No leaks dries a bone. The only thing I can see is it's a stock retainer with black RTV lol I just don't remember what I did.
 
I talked to Mancini today. He said that it is normal for it to stick out of the back of the block a little bit. The seal retainer. And there is enough area for the side o-rings to seal. So my dilemma is I already have this one sealed up. I feel pretty good about it. Or do I put the Mancini one in? lol
 
I use the factory seal retainer, alignment pins, offset the seal halves slightly above the parting lines, and the retainer/block alignment goes where it needs to go. No leaks ever.
 
Well I just undid what I did the other day on Saturday and it looked like it would have sealed. Perfect. I decided I was going to go ahead and use the Mancini and turns out that to Mancini retainer is hitting the rear main bearing cap. So now I've got a clearance at some. This is ridiculous lol

PXL_20230220_213740208.jpg
 
flathead31coupe said:
The engine I just took out I put together years ago. No leaks dries a bone. The only thing I can see is it's a stock retainer with black RTV lol I just don't remember what I did.
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That's how I have done every single big block and slant 6 I have ever built. I never use the side seals for the rear seal retainer. I use RTV and never had one leak.
 
So I just sent them an email and I told them what is going on and sent them that picture. I will call them in the morning. At this point I'm thinking about just going with the stock retainer as said many times above and fill the sides with our TV and let her ride lol
 
So I went back out. Cleaned everything up. This is the third time. lol I did it the way most suggested. And the way I have done it in the past. I Clocked the seal and it seems like it looks good. We'll see. Not saying anything bad about the aftermarket retainer other than I thought it was clearanced and everything had been figured into it when they made it. I'm going to try and send it back. I have to wait on an RMA.
 
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Whoever talked you into getting that worthless bit of bling from Mancini, needs a boot up the ***. I'll say it, it's a piece of junk, yet Mancini keeps selling them, because Mancini suck.
 
The originals work fine, I always first check seal alignment with the crank out of the block and never use the side seals. Just silicone injected with a syringe that has a small juice box straw stuck on the end of it down the sides of the seal block. Push it to the bottom and inject the silicone as you pull it out. You can see it if you look through the side gaps as you do it.
Line honing won't cause seal issues either.
Unfortunately, when you ask a question around here, you're going to get suggestions from those who have a clue and from those who don't.
Only about 15% of the info posted in this place is ever on target. The other 85% are helping like how a 5 year old thinks their helping you in the kitchen. lol.
 
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I appreciate all the input from everyone. The 440 I took out was dry as a bone and it was in there for I don't know how many years and I did that the way that I just done the last one. But I got sucked up to the latest greatest foolproof things. And it may work for somebody. But as you can see it did hit my main cap and wouldn't let it seat flush. I was just under the impression that it was clearanced and had all of the issues removed from it and it would be a great replacement. Live and learn lol
 
flathead31coupe said:
I appreciate all the input from everyone. The 440 I took out was dry as a bone and it was in there for I don't know how many years and I did that the way that I just done the last one. But I got sucked up to the latest greatest foolproof things. And it may work for somebody. But as you can see it did hit my main cap and wouldn't let it seat flush. I was just under the impression that it was clearanced and had all of the issues removed from it and it would be a great replacement. Live and learn lol
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You will send it back, and they'll just sell it to someone else.
 
ns1rm21 said:
Good idea but I think you need oil pressure and the crank spinning to show it it truly leaks.
Here is what I do to check to see if everything is good.
Install the crank, lower seal and main bearings and torque everything down. Put white grease where the seal rides and turn the crank. I’m looking for a pattern that is 1/16” wide. Then I pull the crank and seal out and just put the seal in the retainer and repeat. If it is also 1/16” wide AND the upper and lower seal make contact in the SAME place on the crank you sould be good. One more thing, apply a small bead of “The right stuff” on the back side of the seals and on the seal ends where they contact each other. I also offset the seals in there saddle to make sure that there lined up as well. This is what works for me. Hope this helps.
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I had real issues w/ my stock 440/505 seal, ended up finding the rear seal cap was machined off center on the \bolt holes , was off center when bolted down , none of the above would fix it !
 
famous bob said:
I had real issues w/ my stock 440/505 seal, ended up finding the rear seal cap was machined off center on the \bolt holes , was off center when bolted down , none of the above would fix it !
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I've noticed that most of the seal retainers are not centered, this is the entire issue IMO.

By using alignment pins and dropping the cap over an offset seal everything automatically lines up. The gaps between the block and the seal retainer are usually greater on one side over the other. If you try to center the retainer in the block with the seal ends flush the alignment can easily be off enough to leak.
 
440 Mike said:
I've noticed that most of the seal retainers are not centered, this is the entire issue IMO.

By using alignment pins and dropping the cap over an offset seal everything automatically lines up. The gaps between the block and the seal retainer are usually greater on one side over the other. If you try to center the retainer in the block with the seal ends flush the alignment can easily be off enough to leak.
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I finally installed the cap/seal (under the car)and watched it pull side ways when it contacted the crank , got a new cap from >I dont remember , maybe you know him !---LOL
was still some what ofa procedure to get it right , had to slide it over home made headless studs to get it right ---
 
famous bob said:
I finally installed the cap/seal (under the car)and watched it pull side ways when it contacted the crank , go ta new cap from >I dont remember , maybe you know him !---LOL
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I'm sure that a certain percentage of caps were off enough to pull the alignment way off. Usually the bolt holes have enough clearance to align the seal properly.

The original rope seals were very forgiving. Fore and aft as well as side to side alignment is what causes the problems with the modern seals.
 
Not only fore-aft, but up-down, which I found was bad with aftermarket caps. I noted this in an earlier post on this thread.
 
I spoke with them Saturday morning. Easy to talk to credit my money back to my account. No questions asked. He did note that they have had no problems with those retainers . But we're as nice as they could be.
 
You say you "clocked" the seal. I assume you did the old "trick" of misaligning the seal joints with the block to retainer joints? I never do that. I put it in as designed, put a dab of RTV on either end of the seal, put RTV on the retainer and assemble. Everyone I know whose tried the misalign trick has had a leak. I just don't do it. I hope it works.
 
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