New GM L31 Crate Motor Leaking

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HopHead357

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Hello all. Just got my new GM L31 crate motor in my truck and noticed that it is leaking from the rear main seal area. It doesn’t even have any oil yet and there is a small puddle of oil about 2” in diameter. You can see it running down the inspection cover on the bell housing. Definitely coming from the rear main seal area. Does anybody know if they use any sort of assembly lube or anything that may sort of seep out?
 

Schurkey

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It doesn’t even have any oil yet and there is a small puddle of oil about 2” in diameter. You can see it running down the inspection cover on the bell housing.
Sure it's not trans fluid from the torque converter/pump seal, or a manual-trans gear oil leak from the input shaft? The crank does have a pilot bearing...right?

Kinda hard to believe the rear main leaks when you haven't even put oil in it. Same for the oil filter/filter adapter gaskets, and the oil gallery plugs near the camshaft.
 

HopHead357

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Sure it's not trans fluid from the torque converter/pump seal, or a manual-trans gear oil leak from the input shaft? The crank does have a pilot bearing...right?

Kinda hard to believe the rear main leaks when you haven't even put oil in it. Same for the oil filter/filter adapter gaskets, and the oil gallery plugs near the camshaft.

The oil galleries weren’t leaking and it’s not from the trans. It’s tilted the other way so there’s no way oil could run up that way. And it also doesn’t have fluids in it.

Bought a new clutch kit for it and installed the new pilot bearing that came with it.
 

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Wouldn't it come shipped with some residual oil in it? I assume they test before shipping.

Seems like a question for the place you puchased it from.
 

HopHead357

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Well, oddly enough, it stopped leaking after we pulled the motor back out and took off then reassembles the bell housing, pressure plate, clutch, and flywheel. Inspected everything when we had a part and couldn’t figure out where the oil was coming from. So very odd.

The only thing I can figure is that it was some assembly lube or something that just ran off back of the motor on the crankshaft.
 
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