OM606 Rear oil leak

[Superturbo]

Hi, I have a W210 300 Turbodiesel and I noticed the torque converter housing is covered in oil, but I can't tell if it's ATF or engine oil.
I can't see any leaks from the valve cover gasket, and the oil filter housing looks dry.
Someone told me it could be a problem with the transmission oil pump, but it doesn't make any strange noises and seems to be working fine. Any ideas on what else I should look for?

[Sugar Bear]

Looks like engine oil due to the location. I've never seen ATF make it's way up high on the exterior of a bell housing. Clean it well and watch it.

[Murkybenz]

Sure it’s not fuel ?

[Superturbo]

Originally Posted by Sugar Bear

Looks like engine oil due to the location. I've never seen ATF make it's way up high on the exterior of a bell housing. Clean it well and watch it.

Yes, I thought the same thing, but since I've only had the car for a few days, I don't know if it had a vent or something higher up because I can't see.
I've been told the leak could be coming from the cylinder head gasket.
Right now I'm replacing the radiator, which broke because a fan blade broke. When I'm done with that, I'll clean everything and try to see where the oil is coming from.
Sorry if something I say is not understood, I am from Argentina.

[Superturbo]

Originally Posted by Murkybenz

Sure it’s not fuel ?

I don't think so, at least it doesn't smell like fuel.

[engatwork]

Can you post pic of what is at top of that area?

[Phillytwotank]

Could be valve cover gasket leaking. Standard procedure is to clean everything well and observe for a time to see if you can determine the source

[jdulle]

Mine has oil there too, I thought it was the rear main seal...

[Sugar Bear]

The rear main should show up more inside the bell housing and under the back of the oil pan vs. around the top of the bell. My W123 was pretty cruddy on top of the bell, I'm rather certain it was caused by the head gasket.

[jdulle]

I should have specified, mine is mostly leaking on the bottom.

[Sugar Bear]

Try to catch a sample even a drop on aluminum foil, it will make it easier to distinguish between fuel, coolant and engine oil vs. ATF.

[bigpanda16]

On mine, it appears to be the rear Right hand side oil drain hole in the head gasket that is externally leaking. I'd imagine that the coolant passage near it will be soon to follow and then I'll have to slam a goetze graphite head gasket on it.
You should know if it's oil as it will be black
Fuel is clear and transmission fluid red(if fairly recently serviced)