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Old 01-12-2022, 02:14 PM
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Default Installing BOP rear main w/ crank installed

Any tips or recommendations on installing a BOP one piece rear main with the crank in the block?

I have the engine out and stripped down to the shortblock, and would like to avoid disturbing anything that doesn't need to be disturbed. Should I just bite the bullet and pull the crank to install it?

I believe my block was line honed or bored because it takes a .005 under timing set which I understand may complicate a successful seal install.

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Old 01-12-2022, 03:00 PM
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I would take the crank out. You need to measure the block and the cap to determine which part of the seal needs the most attention.

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Old 01-12-2022, 08:37 PM
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I think that's probably the best approach if I want to be sure it's installed correctly. Any risk to untorquing/retorquing the mains (which are studs) and rods? Can I simply take it apart and put it back together with the new seal?

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Old 01-14-2022, 08:53 AM
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Ouch - these much better pics point towards a minimum of polishing or turning the crank .010 and new rod/main bearings, including R&R on the cam bearings.. What we are not seeing is what is the cylinder bore wear given whatever happened in this engine that scored the bearings. (Dirty or wrong oil, what was found in the oil pan?)
If this was my engine, I would have it at a good machine shop, turn the crank, hone or bore the cylinders, new pistons/rings if necessary, and as long as it is disassembled, get it balanced. Then you have piece of mind and a reliable motor going forward. Yeah - this costs much more $$ than just bearings, but eliminates spinning a rod or main bearing, or god forbid throwing a rod. That was exactly happened to my Bro when we cut corners on his rebuild
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Old 01-14-2022, 11:36 AM
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I agree with Lust4speed. Hard to tell in the pics but that caught my eye first.

Couple of the journals also look pretty scorned to me. Much more so than journals right next to it. Enough to make me think the crank may need to be turned. But I'd have what ever it is showing up in the picture checked first, it might be done anyway.

Certainly appears the engine had some trash running through it. From the way the mains look it also gives me the impression that the main bore alignment needs to be revisited again.

Upper rod bearings do have some wear, but not as bad as some I've seen with engines that had known detonation. If this is just basically a stock engine that could most likely be dealt with in the tuning or maybe fudge around with camshaft selection a bit, but I'd be more concerned with the other problems at this point.

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Old 01-12-2022, 09:50 PM
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I replaced the rear seal on a 70 455 a couple of months ago with the crank and rods still in the engine. One of my brothers spoke to Butlers about it and purchased the seal from them. They actually advised how to do it. It was a two piece seal. I took the mains caps off, then gently raised the back of the crank up. Pulled the rope seal out, and cleaned the seal area. Clocked the new seal how I wanted it and seated the crank and assembled like usual. Worked fine with no problems and was surprisingly easy.

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Old 01-12-2022, 10:42 PM
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It has a two piece in it now. Based on the oil that was on it when I pulled the cap, I think my suspicions about it leaking were right. I pulled the caps off tonight and I'm not loving what I'm seeing in terms of the bearings, so it's looking like this might be a bigger project.





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Old 01-13-2022, 02:24 PM
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Quote:
Originally Posted by Verdoro 68 View Post
It has a two piece in it now. Based on the oil that was on it when I pulled the cap, I think my suspicions about it leaking were right. I pulled the caps off tonight and I'm not loving what I'm seeing in terms of the bearings, so it's looking like this might be a bigger project.





Just an FYI, if going with the regular one piece or 2 piece rear main seal, I prefer to have those serrations polished a bit. Those types of seals tend to not like a rough surface and those serrations can eventually eat at the seal or at the very least wear it down over time. Possibly what contributed to your 2 piece rear main seal leak.

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Old 01-12-2022, 11:20 PM
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it looks like too much permatex was used on that seal. Im not surprised that its leaking by the looks of it . You're taking a chance installing the seal with the crank in because you dont know if the block was line honed to the point where the cap becomes shallower then the block side of the main. But yeah you can do it with the crank in . I haven't been so lucky doing it with the crank in.. Looks like those bearing are put in the wrong side . The holes go to the block not the caps ..

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Old 01-12-2022, 11:54 PM
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I thought the same thing about the holes in the bearings - and the gobs of sealer around the main.

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Old 01-14-2022, 02:07 PM
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"I believe my block was line honed or bored".
Bro - you take good pics which helps analysis. Not surprised of the piston wear versus the bore wear, looks like a little piston slap was going on, more common with forged pistons being a little "loose" if the block was honed/bored and not clearanced correctly (forged pistons expand more than stock cast). And the Valve stem carnage - that is a machining and set-up oversight With bad valve seals, maybe some oil/smoke blow-by was going on?. Not at all trying to throw darts here, just some input based on experience.
You mention maybe going the Stroker route. What else is currently on/in the motor - ie carb, cam, rocker arm type and ratio, valve springs, etc? Was it all stock, or some different stuff when and if it was rebuilt?
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Old 01-13-2022, 09:10 AM
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Good thing you looked into it and took the crank out. No big deal now . Just get some new bearings, put them in the way there supposed to be and definitely check those rod bearing. I cant imagine that there in good shape after running with the mains the way they are..

Good luck....

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Old 01-13-2022, 09:18 AM
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The bearings must have oil holes on the block halves too .. or the engine wouldn't have run for 10 minutes I don't think.

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Old 01-13-2022, 02:20 PM
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Quote:
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The bearings must have oil holes on the block halves too .. or the engine wouldn't have run for 10 minutes I don't think.
Yep, some bearing sets come with holes on both halves. No big deal. He just didn't take a picture of the main bearings in the block, but I'm sure they have holes too.

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Old 01-13-2022, 10:03 AM
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^^^^ My clevite's did NOT have holes on both halve's......I happened to catch that when my son was putting them in as we were about to install the 1 pc rear seal!

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Old 01-13-2022, 10:55 AM
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I got tired of the crap rope seal and constant leaking at the rear main seal. My engine is quite modded, and puts out a lot of crankcase pressure that just overpowers breathers so the oil will always push past the RMS and make a mess. So I was able to make a wire tool and carefully pick out and push the rope seal out at the top of the crank w/o loosening all the mains. Then slid in a Butler 2 pc seal. This helped, but I also added a Butler Crankcase Evac System. No more oil leaks.
IMO that the discoloration is not a issue, the crank looks OK but not the bearings.
SO new Clevites, new seal while you are at it, check the rod and main clearances with the new bearings, and your good to go.
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Old 01-13-2022, 10:58 AM
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The parting areas on the the caps look really discolored .

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Old 01-13-2022, 01:39 PM
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Digging through the forum, it looks like at some point in the past Clevite switched to having holes in both sides now.

https://forums.maxperformanceinc.com...71#post2949271

I could just put fresh bearings in and move along, but I'm worried this will happen again. I'll give the machine shop a call and see what he says. I'll need him to put new cam bearings in at minimum.

Rods look like this:


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Old 01-13-2022, 01:43 PM
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what does the rod side of the bearing look like ?

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Old 01-13-2022, 02:53 PM
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Will get some pics of the rod end of the bearings, but I think they were about the same as the end.

Here's what my mains look like end to end. The middle three bearings are showing more wear. Not sure what that might indicate in terms of clearances or otherwise.



The crank serrations might have contributed to the leak, I've heard they can be an issue. The seal on the whole is hard as a rock. I don't think whatever sealant they used was helping things. It seems to have shellacked over.

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