leaking oil pan, 360 Magnum

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Abodysrule

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I had a leak at the front of the oil pan, tried the stop seal spray stuff. Seemed to work for awhile, stopped most of the leak, just a tiny drip now, but I can't identify exactly where from. It's in the front. It's definitely not the crank seal in the timing cover or the timing cover to block, it's the oil pan gasket. I believe it's at the top front corner(s).

So, for now, since it's a very slow leak I'll drive it, but at some point I'm gonna pull that oil pan and reseal it. You all helped me with the rear China wall leak, great advice there. Have any similar advice or tutorials to point to on the oil pan gaskets? Looks like if I unhook the center link the pan will drop right out.

Brian
 
Only advice I have is use the one piece oil pan gasket.
 
Part number or brand? RTV or other sealant, or no sealant? I've never changed a pan gasket on a 360 magnum, never done a one-piece pan gasket.
 
Is this in an A body?
If so, what you have is an LA 360 oil pan on a Magnum block (Magnums never came in a passenger car, so using an LA 360 pan is how it's done).
An LA pan has 2 notches in the front seal area (red circles), the Magnum pan does not have these and is completely round (smooth).
1723860675741.png

The problem is when a Magnum seal is used, it does not fill these notches and the voids that are left will piss oil like Jed Clampett's backyard.
The 2 most common fixes for this are:
1.) Use an LA 360 oil pan gasket set.
2.) Use the one piece Magnum gasket, but when installing fill the voids that are left with a generous amount of RTV Ultra Black or Gray, let it tack up and then install the pan.

And by the way, the pan won't just drop out after dropping the center link. You'll have to at a minimum unbolt the motor mounts and jack the engine up, drop the starter, possibly unbolt your exhaust or headers, and disconnect or try to move your transmission cooler lines if so equipped- maybe more depending on your car's equipment...
 
Abodysrule said:
Part number or brand? RTV or other sealant, or no sealant? I've never changed a pan gasket on a 360 magnum, never done a one-piece pan gasket.
Click to expand...
Never use sealant on a rubber gasket. I don't know what brand you like. There are several. Summit has them listed.
 
Professor Fate said:
Is this in an A body?
If so, what you have is an LA 360 oil pan on a Magnum block (Magnums never came in a passenger car, so using an LA 360 pan is how it's done).
An LA pan has 2 notches in the front seal area (red circles), the Magnum pan does not have these and is completely round (smooth).
View attachment 1716290414
The problem is when a Magnum seal is used, it does not fill these notches and the voids that are left will piss oil like Jed Clampett's backyard.
The 2 most common fixes for this are:
1.) Use an LA 360 oil pan gasket set.
2.) Use the one piece Magnum gasket, but when installing fill the voids that are left with a generous amount of RTV Ultra Black or Gray, let it tack up and then install the pan.

And by the way, the pan won't just drop out after dropping the center link. You'll have to at a minimum unbolt the motor mounts and jack the engine up, drop the starter, possibly unbolt your exhaust or headers, and disconnect or try to move your transmission cooler lines if so equipped- maybe more depending on your car's equipment...
Click to expand...
Nevermind. I stand corrected. Do it this way if you use the rubber one piece gasket, BUT let it set up and dry completely or it may leak.
 
I used the magnum one piece gasket, cut the front portion off of it, and used the front portion from a regular LA Kit. Yes you have to buy two complete pan gasket sets but oh well. When you cut the magnum gasket make it so it does over lap with the LA front piece just a little but not too much that it is an interference fit. Use silicone where they meet, the install and let it set up thoroughly before use.

I think this site talks about it too: Magnum Swap -your source for Mopar engine swap information.
 
Great stuff! Yes, it's a magnum with an LA pan, so likely it's leaking at those two corners where the RTV is. It's a '67 Dart, but I have the '73-76 spool type (SL6, Schumacher conversion mounts) K-frame. My mini starter doesn't appear to interfere in getting the pan down. Maybe I have to lift the engine, but it sure looks like it'll drop down without doing so.
 
Magnums swap suggests cutting the U out of the one piece Magnum gasket and using the U from the 360 LA timing cover set. See excerpt below. Is that because the LA front U seals better than the Magnum front U piece? Mine has RTV on the corners and on the U piece, from the builder.

5.9 Magnum “One Piece” Oil Pan Gasket
When using an LA timing cover, it is still possible to use the one piece oil pan gasket from the Magnum engines. Simply use the front ‘U ‘from the timing cover kit—you’ll need one to install the timing cover and water pump anyway–and cut away the corresponding U-shaped piece on the Magnum gasket. A little Rite StuffTM where the rubber gasket meets the new U, and VOILA! Leak free fit!
 
Last edited:
Professor Fate said:
Is this in an A body?
If so, what you have is an LA 360 oil pan on a Magnum block (Magnums never came in a passenger car, so using an LA 360 pan is how it's done).
An LA pan has 2 notches in the front seal area (red circles), the Magnum pan does not have these and is completely round (smooth).
View attachment 1716290414
The problem is when a Magnum seal is used, it does not fill these notches and the voids that are left will piss oil like Jed Clampett's backyard.
The 2 most common fixes for this are:
1.) Use an LA 360 oil pan gasket set.
2.) Use the one piece Magnum gasket, but when installing fill the voids that are left with a generous amount of RTV Ultra Black or Gray, let it tack up and then install the pan.

And by the way, the pan won't just drop out after dropping the center link. You'll have to at a minimum unbolt the motor mounts and jack the engine up, drop the starter, possibly unbolt your exhaust or headers, and disconnect or try to move your transmission cooler lines if so equipped- maybe more depending on your car's equipment...
Click to expand...
You sir win the internet today. Excellent post with all of the pertinent information.
 
Abodysrule said:
Magnums swap suggests cutting the U out of the one piece Magnum gasket and using the U from the 360 LA timing cover set. See excerpt below. Is that because the LA front U seals better than the Magnum front U piece? Mine has RTV on the corners and on the U piece, from the builder.

5.9 Magnum “One Piece” Oil Pan Gasket
When using an LA timing cover, it is still possible to use the one piece oil pan gasket from the Magnum engines. Simply use the front ‘U ‘from the timing cover kit—you’ll need one to install the timing cover and water pump anyway–and cut away the corresponding U-shaped piece on the Magnum gasket. A little Rite StuffTM where the rubber gasket meets the new U, and VOILA! Leak free fit!
Click to expand...
I’ve done it both ways, and I prefer the magnum one piece gasket and fill the voids with “right stuff”.
 
Abodysrule said:
Magnums swap suggests cutting the U out of the one piece Magnum gasket and using the U from the 360 LA timing cover set. See excerpt below. Is that because the LA front U seals better than the Magnum front U piece? Mine has RTV on the corners and on the U piece, from the builder.

5.9 Magnum “One Piece” Oil Pan Gasket
When using an LA timing cover, it is still possible to use the one piece oil pan gasket from the Magnum engines. Simply use the front ‘U ‘from the timing cover kit—you’ll need one to install the timing cover and water pump anyway–and cut away the corresponding U-shaped piece on the Magnum gasket. A little Rite StuffTM where the rubber gasket meets the new U, and VOILA! Leak free fit!
Click to expand...
Isn’t this exactly what I just said?

Also google scram speed. They make a gasket kit for the pan and front end for around$80
 
Do you or anyone have any information on that scram speed gasket? There is a description but no pictures.

brian
 
jbc426, in another thread on this forum, had a great idea, see quote below.

"...I just hammered the front notches down flat on my LA 360 Milodon oil pan and used the one piece Magnum gasket and a small squirt of Permatex Ultra Seal in all 4 corners of the pan and on the threads of each oil pan bolt on my 5.9 Magnum. It's remained leak free for several years now..."
 
Abodysrule said:
Do you or anyone have any information on that scram speed gasket? There is a description but no pictures.

brian
Click to expand...
i saw that too and took a quick poke around to see if i could find pics, but no love on that front.

i'd be interested if it's a real deal piece and not some hokey home brew thing. i can cobble with the best of them and i'm not shelling out hard earned kajiit kuble koins for what i can very well arts and crafts at home.
 
I think just hammering them into Magnum configuration as described by JBC426 sounds like an elegant solution. No need to fill with RTV and no need to modify the Magnum gasket.
 
...the only downside I can see there is that the LA front U gasket fits the LA pan lip way better than the magnum gasket.

Anyone have pics of how/where they cut the magnum gasket to mate with the LA U gasket?
 
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