Rear Main - still leaking

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ClarkDart70

ClarkDart70

Street Machines Limited
Joined
Mar 17, 2011
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Plainfield, IN
Ok Guys,
I put a new rear main in the 318 last week with a new trans pan seal and today I drive it over to have some new tail pipes bent and when I get home its starts a slow drip.
I siliconed the joining areas of the seals under the main cap and torques everything to spec but I'm still getting a leak. Any thoughts aboyut what I may have missed here? The journal on the crank was in good shape (No scoring or grooves that would not permit a tight seal against the lip of the rear main).
And I did not put it in backwards.

Thanks for any input,
Clark
 
Yup cudaspaz is headin in the right direction. There are a lot of things that can look like a rear main leak. Valve cover gasket, intake end seal, oil sender, even the head gasket. the oil can drool down the back of the engine around the bellhousing area and look just like a rear main. If it was mine I would be back there with a mirror verifying it.
 
Green1 is right. You need to stagger the seal about 3/8 of inch and put the silicone on the ends. Could be rear cam plug also. Hunky
 
I'll check the other sources tomorrow. Stagger the seals? The sealed with silicone where the rubber and cork met, but what do you mean by staggering them?
 
Sorry, brain fart. I was thinking of the seals for the pan. I sealed the cap and main with silcone. Where is the rear cam plug?
 
You don't install the one in the block flush on both ends; one end hangs down, the other end is up in the block. Then match the seal in the cap to match that. Having it flush tends to leak.
 
I know the feeling well. Here is a little bit of my journey with a 360. It still leaks to this day! I don't know what the heck it could be. The only thing I can come up with is that it is leaking around one of the ports on the back of the engine block that is used for engine cleaning purposes (cam plug). It leaks very slowly and it is just enough to make one go crazy.

http://www.forabodiesonly.com/mopar/showthread.php?t=75809&highlight=seal
 
I don't remember the crank main having ends. They must have changed, or we are talking about 2 different seals.
Ahh, you are talking about the pan gasket; I am talking about the one in the rear main cap and block. The crankshaft can leak, above that pan gasket. The pan gasket seals against the bottom of the block, not the crank running thru the cap. Tool is sneaky pete. Unless you have a one peice; forgot the year they went.
 
I have the two piece rear main, the lower half has little rubber ears that sandwich between the block and cap.
If I read you right, you are saying to rotate the top and bottom pieces so the ends are not flush with the mating surfaces of the block and main. Rather than the meeting points for the ends of the seals being at 3 and 9 oclock, the seal would be at say 2 and 8 oclock, while the cap and block are sealed with silicone?
 
That is how I fixed mine. I cut the tabs off and staggered the seal and used black permatex sealant at the ends. It fixed my leak.
 
Offsetting the seal is great advice.....and I'm not arguing the point...BUT, the factory never did it and their seals didn't leak when new.
 
Well, as it turns out, it wasnt even my rear main. It was the rubber strip that seals the back of the pan. It had a tear in it. Thanks everyone for the input!
 
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