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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Got oil replaced.  Plugs in.   Did 3 or 4 starts wo coil.  Replugged coil.  Started up.  No exhaust really makes it sound like a drag car!

Anyway,  ran about 15 seconds,  oil light still o .    Turned off.  Statred 2 more time .  Oil light stayed on.

Decided to stop and ask if i should prime, or let it run a little more to get the oil flowing to point of turning off lighr?

Dnt want to burn up testing a leak

How long would you say  you ran the engine in  total —the three startups you did with the coil back in ?


20 to 30 seconds.  3 times

Not sure why you would start with the exhaust uncapped. Just to save time? You have just removed and reinstalled a bearing cap. I would want the engine as quiet as possible so I could hear any issues. Not to mention, if you get under that exhaust manifold end with it running you will burn your face off or anything else that gets in the way of the fire hot gasses.  I remember in my younger foolish days after running at the local drag strip with headers uncapped, I decided to drive home like that... only 3 or 4 miles, but had accidentally pushed the transmission shift cable from my B&M Quicksilver shifter over just enough where it got enough heat from the exhaust to burn it in two. I remember having to crawl under the car and manually push the lever to shift the car until I got another cable.  

Lack of confidence the seal is holding due to the installation i outlined earlier and hving to detach it all again.  

I Just love —recalling our Younger more foolish days —when some unforeseen  random thought pops into our minds about a past experience— and makes  you Smile ( all to yourself —LOL  !! )



Do you understand how to use —( I do not ) the tool in the manual that they show you  how to make from the drawing in the manual 

Would you install the tool in the top of the  block bearing seal channels  large side first —and then put the thin part into the new seals center grove and push and pull the new seal into place then sliding the tool out on the other side  ?

OR    does the thin side go into the  block channels first so the larger side keeps the seal off the groves completely until it has been drawn across the block channels  and then seated into the  block groves ?

I think my second though looks more reasonable to prevent  any seal damage —as I think this through on this post 

The tool would keep the new seal —above the channels ( until removed ) and safer from damage until it is removed to allow the seal to seat into the  block channels ( no sealant -only lithium grease on the seals bottom and sides ? ) 

That is the best I can figure out but not 100% sure 

There are no instruction to be following in the manual regarding the tools use 

Appreciate your thoughts on the subject always !

I know being sure to use the tool was one of your first thoughts on the subject 



Start the engine and let it run for a minute or two - light should go off 
Do you see any sign of leaking ?

Let’s see the results before you judge you repair 

Look at it this way — You should be real good at doing this a second time with your experience now 


Tony, the special tool inserts into the cap as to protect the seal from the sharp edge.  

Kim, since the oil light is not coming on, I would hook up the exhaust and prime the oil pump.  You can either remove the oil filter assembly and fill the tube to the pump. Start it up and run it for 10 seconds.  If it doesn't prime after a few times, you will need to pull the distrib and fill the oil pump again.  Spin the distrib until the pressure returns. 


which end of the tool goes in first ?


Just reread the manual —-looks like the thin end of the tool goes into the channel in the groves of the cylinder block and then using the thicker part of the tool as a shoe horn feed the seal across the cylinder block groves to the other side —remove the tool and seat the seal  down into the groves ( using lithium grease to aid )


Not for nothing but - - this rear engine seal design is really really poor ( sucks ) 

The smallest amount of seal seats on the crank journal after studying the pictures with the lower cap removed 

You can see the -thin seal material worn on to the crank journal in the photos 




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