Per Tony,  i am starting a new thread on my adventures with this rear main leak,

i posted a video on a 390 engine of a rear main seal replacement but the engine was out of the car,, gave some insight as to sealing and materials etc.

One of my neighbors has a hoist,(yeah!) and has allowed me to use it,, makes it a lot easier than rolling around on the asphalt in the street and is enough higher that its not too confining under there.  I did have to pay attention to the lift points though as it seems you cant just put those lift arms wherever you want..

As of this evening, I have taken the exhaust loose, the steering loose, and the starter is out,, took about 4 hours to do that.  I guess there is nothing earthshaking to report on any of this.  Tomorrow, I will take the pan off and proceed from there.

To be clear before proceeding.

the 63 manual says to insert the bearings in there slots, do not pull off wax coating as that will aid in insertion.  I do not see any wax on my gasket, so my guess they had it on the old ones.,, 

Now, the question here is,, do i add a touch of oil or something to aid in that insertion process,, the manual does not suggest it, as i describe above, or, just insert dry, as is..

it does say apply rubber cement to cap and block mating surfaces, and gasket ends, but that is the only reference in the 63 manual regarding lubricaitng the seal for installation,,  so is that correct?? insert dry??

the you tube video says to use lubridation after insertion so it wont be dry on start up, so i plan to do that as well.

i will try to take a few photographs of things once i get the pan off,  i m sure most have seen the underside, but its my first venture in there and post them for reference.

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Thank you for locating the repair on the bearing cap and your expertise on the subject which is priceless in this case 

Looks like there is no easy way to  be getting  this repair done correctly as it stands 

Kim will have to be making a decision on which direction he will choose to go 

Anything from a short block to a completely new rebuilt engine may be the way to go 

You can then sell all the good parts from the current engine ( to off set the cost ) or keep them for the future of your own car 

A difficult  and unexpected situation to be dealing with 

I just cannot say — Enjoy — in this case

ok,   well, nothing like throwing a turd in the punchbowl!!

So, please advise to the following as I have no experience at his level..

Option 1:  If i put the car back together, with the new seal in and the rest as is,, i am guessing that i will continue to suffer a leak, maybe not as bad, but a leak.   As someone wrote, the bearing will have to be addressed at some point...  

what else can happen if i continue to use for say, couple months till i can make a more permanent decision , the car was running great, thats the real bummer of it.

Option 2:  I get one of those rebuild kits,, seems they run from 1200 to 2k depending on what all you get.   what would appx labor cost be on a rebuild..roughly, i know different areas have different levels of cost.    if it would save me a couple grand to do it,, i would, but I'm not sure i have the skills for such and endeavor.   Can i use the same block that I have?  or do i have to get another one,, will i have to replace the crankshaft or does that come with the kits,   I dont know the what does and what does not go with the re builds.  What is still good on my block,,, is my crankshaft still good,, assuming the bearings are worn?

Option 3:   LS swap,, a bit more costly, but a more modern solution with the potential of more access to parts down the line, better gas mileage, able to use the lower cost fuel.

My usage level of the car is a lot. I drive it 3 or four days a week, usually hundred mile a more at a pop.    So i am a regular user,, i use my truck when i have to haul work stuff.. otherwise I'm in the 63.

Any other options to review?    if so, please give me some semi detailed explanation of thse options, I would appreciate it 

I am just to much of a novice to know the options and there cost...

Is there any possibility of finding the right person to take the time to rebuild the bearing cap doing the metal work and  finishing work to make it new ?

Then replacing the crank bearings  that are now worn that have caused the seal damage  as  Mark suggested could get the engine running again 

We need  to find a metal Artist to repair the end cap 

A very  very good machine shop might be a good place to start 


Ok, clearly it was just the angle, that cap is intact.  
I can't figure out why anybody would attack it with a cutoff wheel like that, but who knows?   
I don't think you necessarily need to replace it, because of the risk/reward.   These seals are known to leak anyway, so if you replace the block it could still drip once in a while, so why go through it.  

My only concern is where the seal surface was scored by the cutter, it might allow a path for the oil to go around the new seal.  You might consider setting the seal half in the cap with a bit of jb weld on the outside circumference and letting it cure in the cap before installing it.    That would hopefully close off any routes behind the seal.  It might work without any sealant, it's tough to say, but I could see the oil finding its way out thru the groove.     If you use jb weld or silicone, don't use much, you don't want it to break off and clog the sump screen(which you should clean while the pan is off btw).    The outside surface of the cap (which projects out into the bell housing) looks pristine, so it should work if you can stop the oil from getting that far.  You wrote that it was only leaking a small amount before, it shouldn't be any worse with a new seal.

in those pics, it doesn't look as bad as I had thought, but it does make me wonder what some people are thinking.   I can't come up with a reason why somebody did that.

Could u please draw on one of the photos i hv sent were you suggest putting the jb weld? If you need my emsil or something let me know, for a long description.

I can say that the seal was quite a bit thinner than the replacement seal.  I dnt know if its by design, but the fat part in the rear was no thicker that the front

Thought id add some general photos for the record of the bottom of engine when first pulled apart. Mostly of the rear bearing and crank shaft area.  

I circled the part that would concern me if I were reinstalling the seal.  It looks like the section that the seal straddles is fine, so it shouldn't leak.  But i'm limited by my perspective, seeing it only through small images rather than in my hand.  
The seal has a U shaped groove that fits over the machined section of the cap.  I'd probably use a small amount in the groove, if the grinder hit the raised surface, which it may have.   It may not even need it, if that cut that I circled stopped exactly where I can see it.  If there is a score where the seal fits on, though, i'd use it.    I wouldn't use much, only where it's cut, you don't want to change the diameter of the seal, and only if the cutter touched where the seal will install.  

Ok.   So pardon my ignorance, but you are saying mix up some jb weld and put it on the part of the seal were it will be at or near those cut marks,  just enough to seal off oil that may hit at that point of the seal and the cut marks.

Is that correct?  Basically a dam at the cut marks on the seal?

I marked off in yellow where the seal lands on the cap.  if this is pristine, you're in the clear, go ahead and install the seal dry.  But if the cutter hit any part of it, and there's a scratch on either the side or the top section of that groove, and it won't sand off easily, you'll need a bit of epoxy in the groove of the seal.  
in this pic, it looks fine, all the cuts are in non-essential areas, but I don't have it in my hand, and I can't see the whole thing.  So take a good look at it and check it out.   I may have overreacted in horror at the first sight of it, when you sent the other pics, it looks to be in better shape, sorry to have scared you so badly, it looked destroyed in the first couple shots.

Yes,  if i remeber right, the part the seal goes over is fine,  just the nxt lip has the damage.

No problem on the scare, i was a bit shocked when i saw it when it came out with my limited knowledge of things,  i just didnt look right at all

Unless you are ready for a full rebuild and several thousand out of pocket, I would note this issue, install the new seal, and enjoy the car until you are ready for a rebuild. As long as the seal is "sealing" against the crank, the cuts in the insert grooves should not affect anything. Not sure how much it was leaking before, but hopefully with new seal pushed into the less than perfect rear main bearing cap, it will allow you to continue to enjoy the car for the foreseeable future.  If you were ready for a rebuild anyway and ready for the expense might be a good time to consider the rebuild and sourcing another cap so it can be matched to block when honed.

Very very glad this issue  has turned around as it has 

It was getting scary there for a while 




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