340 rear main seal question

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downsr

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I have a leak at the rear of the engine it is either the pan gasket or rear main seal.Was going to just try the pan gasket first but thought might as well change rear seal .Do you need to loosen rear main cap to put the seal in .What do you re-torque it to.If anyone has some info on how to do this i would greatly appreciate it.The engine is in the car.
 
85 foot pounds and you will have to completely remove the oil pan, oil pump, and rear main cap.
I used an old screwdriver with a 1/8 shaft ground flat on the end to get the top half of the rubber seal loose and started out.
Just center it on the seal end and a few taps with a hammer should do it.

If it's a rope seal you will need a sneaky pete seal puller.
A 3 inch deck or drywall screw works also, but you do have to be carefull not to scratch the journal's sealing surface.
 
Going to put new seal in tomorrow.Was a very big ordeal just to get the pan off the duster.Never want to do it again.So should you stagger the seal in the main cap or put it flush with the cap.Or any information or maybe a web site that shows a seal install would be great.Would appreciate any info, so i never have to do this again.tHANKS
 
the only rear main seals that I have changed were in a ferd 302. And when I put the new one in I staggerd it, made sense to me.
 
You can't stagger the rubber one with the "arms" coming off the top piece...
 
So if you have the seal with the arms on one of the pieces they are not to be cut off and stagger. Just put the seals in flush with the cap and block.How is the white tab that is supplied with the seals used.
 
downsr said:
How is the white tab that is supplied with the seals used.
Click to expand...

it is used to run around the seal to make sure the lip is not rolled under the crank .put a thin layer of permatex on the main cap and block mating surface .
 
Wow, I think there are some levels of humor that are better left unsaid. If you were trying to locate it. Congrats, I think you might have found it.
 
They call the little extensions on the edges of the seal "wings" and the little white plastic tab with it is for ensuring the outside seal edge doesn't get trimmed off when sliding it into position in the block. (A shoe horn if you will)
You can't offset this seal, and the tabbed (winged) half goes in the main cap.

(MAKE SURE you put it in the correct way or it will leak like a pig)

A tiny little dab of silicone on the very end where the seal halves meet and a TINY bead of RTV from those wing tips across to the pan seal area is used.
TINY as in a film where the color of the RTV is barely visible is fine, and you want to get all the way across and around the corner the seats into the block.
 

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These are great tips as I will be doing this too in the not too distant future.
My engine is out and I'm buying parts as I can afford them....

Thanks for the info.

Jeff
 
Good luck and may it seal for a long time... :thumbrig:

Way to go!!! :thumblef:
 
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