318 Oil Pan Gasket/Sealing techniques?

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A Mopar

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I've got a 318 that is still in the vehicle, I'm putting a new oil pan gasket on due to it leaking profusely in the past. I want to do this the right way and not deal with leaks in the future. I have thoroughly cleaned the pan, straightened the pan rails and bolt hole openings. I have purchased the felpro cork gasket set that also has the two rubber end seals.

1. Should I use a gasket sealant, like permatex high tack, to glue the cork gaskets to the oil pan? Should this also be applied to the surface of the engine block?
2. For the rubber end seals, should there be any gasket sealant or gasket maker(RTV) applied between them and the pan, and/or between them and the block?
3. When tightening the pan bolts, I should tighten only until snug, not to deform the cork gasket correct? Since they wouldn't be tightened to the factory torque spec, to prevent unwanted loosening, should blue loc-tite should be used on the pan bolts?
 
Not sure they make one for 318, but I run the rubber one piece gasket for my 360. I made little wooden half circle blocks for ends and screwed them to plywood with blue masking tape on it. Then I RTV the gasket to the pan and put weights on the bottom of the pan to compress it a bit. Then I let it fully cure. Take it off the pan and RTV it to the block and just tighten the bolts enough to make contact all the way around. Let it cure fully and then snug up the bolts. It works for me, I hate oil leaks. I’m very stingy with the RTV. Doing it in the car it’s hard not to dislodge the gasket, why I “glue” it to the pan.
 
Learned this from a commission mechanic friend on small block Mopars, so I know it works... Permatex high stregnth Ultra-Grey in the caulk gun tube. Apply a thin layer 1/4 inch wide bead to the pan gasket and seal surfaces and smear in place and let it skim over. Put your gaskets and seals place and repeat the process on the gaskets and seals. After it tacks up some wipe up any excess inside, and then install. We used an Hitachi 1/4 inch drive electric impact wrench to tighten the bolts with. Never seen one leak, and they're something else to get back apart.
 
Don’t use silicone on a gasket. It makes them too slick.

Get some Gasgacinch. Apply a THIN coat on both sides of the gasket and the block and pan rails.

Let it sit for 10-15 minutes and bolt it together.

You can (and should) use silicone at the corners of the pan.

Anything slick like silicone has no business being on a gasket.

Plus, Gasgacinch allows you to get the pieces apart without using chisels and 5 pound hammers to get **** apart.

Someone doing that needs their *** kicked for doing it.
 
Make sure the pan flange is straight, don't over torque . Don't use cork if you don't have to. Silicone where the end seals meet the flat gasket.
 
Next , is your pan leaking or your rear main seal? I haven't had a problem with the rear main seal before, but do now. Just duplicating what I have done in the past, and it's not working.
 
The rear main on an LA is 2 piece, silicone dab between the halves, also silicone where the main cap meets the block again a dab...I also cut the rear main seal tabs off and rotate the seam so that it doesnt align with the seam of the main cap and the block if that makes sense. If everyone already knows this please disregard.
 
Did half of that, was going to cut those tabs off this time. Though I haven't had a problem in the past, I obviously am doing something different. Can't continue to do the same thing and expect different results! Thanks for the tip, I had already thought about cutting the tabs and rotating the seal.
 
CRUZE 418 said:
Next , is your pan leaking or your rear main seal? I haven't had a problem with the rear main seal before, but do now. Just duplicating what I have done in the past, and it's not working.
Click to expand...
While I had the pan off, I replaced the rear main seal as well. The engine has a 1967 casting date on it and I don't think it has ever had the pan off of it. I'm replacing the timing cover gasket, front crankshaft seal and valve cover gaskets while I'm at it. Will likely do the intake manifold gaskets too. Engine is coated in oil everywhere. I got the pan cleaned up, painted and ready for reinstall. I pulled the trans out a few weeks ago to do a clutch and the bellhousing was coated on the inside with old oil and grease so that prompted me to fix all of the leaks before it goes back together. Don't want to ruin the new clutch.

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I too faced your same problem with my '72 318. In my case, it was time to overhaul a 50 year old engine. Wasn't really sure what the actual mileage was. For me, it really wasn't worth my time to do all of that cleaning and to renew the gaskets and seals, and not just overhaul it. I could afford it. You should probably replace your timing chain while your at it,and take a good look at your camshaft.
Good luck sir!
 
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CRUZE 418 said:
I too faced your same problem with my '72 318. In my case, it was time to to overhaul a 50 year old engine. Wasn't really sure what the actual mileage was. For me, it really wasn't worth my time to do all of that cleaning and to renew the gaskets and seals, and not just overhaul it. I could afford it. You should probably replace your timing chain while your at it,and take a good look at your camshaft.
Good luck sir!
Click to expand...
I thought the same thing about pulling it out for an overhaul but it runs so well as is, so I really hate to do it. It will get a new timing set for sure while I have the front cover off. I’ve got a lift so it takes a lot of the frustration out of doing something like this.
 
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