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440 oil pan gasket. Ultra gray rtv or nothing?

Sonny

It’s all fun til the rabbit gets the gun.
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Since my ‘78 440 swap in December, the oil pan leaks like nobody’s business. I used the black composite gaskets that came with the windage tray and used aviation Permatex between layers. Fail.

Gonna change gaskets this weekend. I bought Felpro 1834’s with the metal center. Had good reviews online. Half the threads online said they used rtv between layers and the other half used none, both without leaks. What do you think? Dry or gooey? I’m also installing Milodon studs in lieu of bolts.
 
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If you truly want no leaks, clean the surfaces with laquer thinner. Use a beed of black RTV, and toss the gaskets in the garbage can.
 
I used black RTV and felpro basic gasket
 
How did you use the two different products?
 
Did you over tighten the pan bolts and made the gaskets squirm?
 
If you truly want no leaks, clean the surfaces with laquer thinner. Use a beed of black RTV, and toss the gaskets in the garbage can.

I've done this with success too.
 
If you truly want no leaks, clean the surfaces with laquer thinner. Use a beed of black RTV, and toss the gaskets in the garbage can.
did you sandwich the windage tray in there too?
 
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I bought the Milodon gaskets that are designed to not crush and squirm like cork. I used ultra grey between all the layers, but a very thing layer with my finger spread out...not a huge bead. I have a windage tray and zero leaks. I did not torque to spec because with that many layers the torque value will crush the gaskets.....just seat firmly and then just check once ran hot once.....no issues here.
:thumbsup:
 
Sorry Sonny not Moroso but Milodon...... here's the link! Like I said didn't crank it super hard. The other thing is my Milodon pan has a real nice firm lip that the gasket sits on so the pan bolts don't distort the pan rail at all when tightened. I see you got the Felpro deal which should also not crush and work well!

https://www.summitracing.com/parts/mil-40700/overview/make/chrysler

mil-40700_xl.jpg
 
too much torque on the pan bolts can cause problems. I think the spec may be 200 in/lbs? but I could be wrong.
The keep the bolts from coming loose I put Blue loctite on them.
The all-in-one gasket/windage tray seems to seal good for me. I have only used them on two engines so far, but they sealed very good.
Don't use RTV with that gasket/windage tray, it will eat into the seal built into the gasket.

https://www.jegs.com/p/JEGS/JEGS-Big-Block-Mopar-Windage-Trays/1660861/10002/-1
 
So I got the pan off. Looks like my $49 eBay Chinese pan is the problem. It has longitudinal recesses on the gasket surface and the area around each bolt holt is raised about 1/16” inch. This thing never had a chance of sealing.

You know where this is headed. I need a 5” deep stock 440 pan with flat gasket surface. Mancini? 440 source? Other?
 
Whichever pan you get, I would recommend you get a pair (if using a regular windage tray) of Superformance pan gaskets. Follow his instructions and you'll have no leaks...I clean all mating surfaces good with mineral spirits, then again with alcohol to get the mineral spirit residue off. Wear rubber gloves to keep sweat and skin oils off and the RTV will adhere nicely...putting the final tightening to 15 ft/lbs won't squish or distort those gaskets, even with a tray, if done correctly. Good luck!
 
414EEDD9-26DA-483D-9370-00EA37368861.png
Thanks! Going with this:
 
I use Ultra Grey RTV. But I also use a gasket. Why? Because with pure RTV getting the pan back off is a nightmare. The generic rubber coated black gaskets work fine. Absolutely no leaks if clean and used with good RTV . Even the tough small blocks seal. Here's one done 16 years ago.
Doug
20170215_185422.jpg
 
I use Ultra Grey RTV. But I also use a gasket. Why? Because with pure RTV getting the pan back off is a nightmare.. View attachment 779967

Yes! Let the gasket tear and put a new one on. Much better than struggling to remove a pan and bending or gouging it up in the process..
 
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