Kupnamauto

Good day
There is engine oil in the cooling system. The engine is OK, does not pressurize, does not smoke, runs regularly, there is no emulsion on the engine cover,
Where could the oil get into the cooling system? (The oil is definitely motor oil), please advise. Best drawing of oil coolers. Does the AMG 63 use an exchanger for the filter?

Thank you for your reply and I apologize for my English

chassis

Welcome! Please post a photo of the C63.

Sorry to hear about oil in the coolant. Failed head gasket is a leading cause.

Because this is your first post on the site, you may not yet be familiar with the layout and the search feature. Do some browsing, and use the search feature. You will find similar posts and likely also options for repair.

Jasonoff

AFIK, transmission fluid is the only thing that touches compartments with coolant. It cycles through the right side end cap of the radiator to get it up to operating temp quicker.

roadkillrob

So it is pretty much covered above, there is only really 2 ways to get oil into the coolant, transmission fluid is most likely as it goes through the radiator also, headbolt failure could allow a tiny bit into the coolant, but more typical is coolant in the combustion chamber and exhaust in the coolant, getting oil into the coolant with a bad headbolt would require oil in the combustion chamber, which is possible if the PCV is pretty bad and your car is sucking a fair bit of oil past the PCV.

So first thing, stop driving the car immediately if you have not or you may damage it much more.

Second how do you know for sure it is engine oil and not transmission oil?

Kupnamauto

thanks for the anwers. I'm not entirely sure right now that this is engine oil. But the oil in the tank is black. Transmission oil would be lighter ... Is that so?

roadkillrob

What year is your car, transmission oil color varies by year, but can be pretty dark depending on miles on it also, the new cars have a green/blue color early cars was a darker red color (before 2011) and can look pretty dark red/black when used.

Key will be determining if it is trans oil or engine oil, trans oil is more likely and if it is a failure of the oil cooler/radiator then there may be coolant getting into the transmission also.

One easy test is there is a pretty simple kit to test if you are the headgasket has failed https://www.harborfreight.com/combus...xoCMUoQAvD_BwE

If that comes up negative then there is really not way engine oil is getting into the coolant and it is likely trans oil.