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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Do follow Russ’s instructions on priming  the oil pump by removing the oil filter housing which is the easiest way if that works 


Dropping the oil  pan has the same affect as draining the oil from the plug to change the oil, meaning, you should NOT have to prime the oil pump!   If you have added the correct amount of oil, have not touched the oil pump, I would run a couple of minutes. Perhaps pop the valve covers off and run some oil over the rocker arm assembly and tighten back down ... if it makes you feel better. Often when you change the oil it takes a bit before the oil light goes off. I understand being cautious but dropping the pan should never be a reason to have to prime the oil pump. Read your shop manual and it will say nothing about priming the engine under oil pan installation or rear main bearing seal replacement. 

Yes, i saw that video in my research.  Because manuql didntvsay lossen all caps  i didnt do that.  Remainder i did as the video shows, which pretty much follows the manual.  I can tell you, that is a tight fit,  loosening may be a solution

Good video. I offset my rear seal when I rebuilt the engine. As far as adding RTV sealant or not, it was interesting to hear him say his packaging said no sealant. I had to go by shop manual as my seals were part of the rebuild kit and no individual packaging or instructions. So.. I think I used RTV sealant, and offset and still get a drip leak when cold. I have tried not to do a deep dive here as Tony and Kim are 7 pages into this just putting the thing back together but it is my opinion that these rear seals continue to leak, especially when cold and the seal has shrunk a bit, because of the slight groove created by the crank journal rotating literally millions of times over 55+ years on these 100K+ mile engines. If you can wear a groove on the front on the harmonic balancer I am sure a groove can wear on the crank where the seal hits it. When I pull my engine out again I plan to do some close inspection and measuring and check out different rear seal offerings. 
The only thing I question on the video is whether to loose all main bearing caps?  Just dunno? It would basically eliminate the need for a special tool but you better be in a position to get the right torque on all those bolts and that is not always the easiest thing to do with engine in car. Anyway, it is a good video .. .always good to see the parts in hand. 

Strange that the 63 book does not mention using the tool to insert the rear main seals, but the 64 book shows the tool and gives dimensions to make it. 

When I did my engine in 17, we modded the cap to take a later/better style set up from memory. I'd have to check with Shane, but I know we run a different rear seal over standard.


Do pls find out what you can about the alternative rear main seal 


The tool was introduced in the April 1963 Serviceman Bulletin on page 21.   This would  have been well into the 1963 model year production and long after the Shop Manual was printed. This is 1 of at least 3 entries in the SB's regarding the rear seal.
Here is the introduction of the tool:

I really was thinking about loosing all the caps all along  but was not sure 

In the car that would drop the crank a bit the more room the better 

I do like his idea about using the sealer where he did on the two cap ends 

This possible could be a further solution to solving a leak in that location 



Run the car until the oil light goes out ( per Jason ) — it will- oil has to move around the engine 

Check under the car for any oil loss you may have and report back 



Do you have any issues with your rear main seal leaking at any time  engine is hot or cold ? 
Jasons and mine only leak  a little after cooling the engine off after use 

i am realizing that the Best Gaskets that was used in Kim’s case is an updated version of that seal most probably with a more current gasket material so that may be what you are referring to 




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