Welded oil pan and spun bearing

Hello everyone, this is Eliott from the States.

I recently got a '94 SL, really nice body and a sunroof (with minor issues). Guy that I bought it from said he was driving and it started knocking all of a sudden. He drove it home. Then to a shop, they let it idle and check it out, then he drove it back home after a rod knock diagnosis. Parked it for a year until I came along.

So i’ve been busy doing other things waiting on some time to work on it. I pulled the oil pan today and there wasn’t much metal in the pan. Brass and silver shavings so, i imagine that’s a lower layer of the bearing but could be a thrust washer, i’m not too familiar with these engines yet. But the small amount of flakes and overall lack of shavings tells me its probably just one journal and not super horrible.

Anyway, I found that the oil pan has a weld bead all around all 4 sides.

Pretty sure my oil pan is not stock. Pretty sure i’m not supposed to see welding bead all around the 4 sides where … I guess the bottom was cut off and fixed and welded back on? Which begs the question, is the oil pan the same dimensions as before? It’s fascinating though, the weld bead is almost invisible on the inside bc it lines up with the reinforcement plate/baffle at the top. Wild

I’ve seen that i can get used oil pans here and there for not too bad, worst case using the playdoh trick to check the clearance between the pickup tube and the oil pan itself. This may not be the problem that caused my engine (previous guy’s engine? our engine?) to fail, but i’d be mighty silly if I didn’t check it, maybe put tape over the pickup tube screen first and then playdoh and then seat the oil pan by hand. Remove carefully and measure how much the playdoh was compressed.

Anyway, what do y’all think? Any crazy oil pan stories? Advice from someone from a similar situation? Is that reinforcement plate what was welded in there? Do other oil pans not have that baffle? The weld looks pretty good on the inside and is right at that baffle.

Well. The diagnosis is going good. I removed the girdle plate with the main bearings first and found where all the brass shavings came from.

3 of the rod bearings have no damage at all, 2 of them only have minor wear, but the last cap i removed was cylinder #4 and it spun the bearing for sure. Bearing is wafer thin and you can see where its been melted and flaked off and the tabs are gone and it was spun and half stuck to the crank journal.

I’ve read it’s usually the center bearings that spin, at least on the twin turbos because that’s where the oil feed branches off for piston oil jets or something. I don’t know. I’d like to find out why this happened. Lots of checks to make.


A friendly person on reddit pointed me to this article and you can see clear as day the welds on the outside of the oil pan and the baffle inside. So this tells me mine was not frankensteined. Further, 3sx states they measured and found 8-10mm clearance between the oil pump pickup tube and the oil pan, so that’s a very valuable spec for us.

Kind of a neat article about how much oil is in the pan when your dipstick says low.
… I guess that gives me my answers here, I have a stock oil pan and if my clearance check between oil pan and oil pickup screen is less than 8-10mm then my pan is still dented.
Thanks to everyone who read this and wanted to help!

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My oil pan is exactly the same as yours.
I was curious about mine as well but looked at a few pictures and Could see a weld there also.