Oil in Coolant Reservoir. Replace Oil Cooler?
 

MB dealer found oil (assuming engine oil) in coolant reservoir on my 2006 E350 4matic. They have suggested replacing the oil cooler and seals. The cost is $700.

Does anyone have experienced the same problem? Is replacing the oil cooler and seals the solution? Any DIY help

First I owe you an apology---I was doing something from memory and not checking the documentation!!

On a 272 or 273 engine the oil cooler is also cooled with engine coolant and therefore your attachment is very correct.

I am sorry for the confusion I caused!!

My guess, transmission, nothing that can't be fixed without changing radiator and transmission.

Insufficient evidence
 

+1 on Plutoe's thoughts. The dealer appears to be guessing in re. the source. More facts and diagnostics are needed before beginning repairs.

relinuca

I removed the similar link. However, I am confused more. On the repair quote by the Mercedes dealer, it said "COOLANT RESERVOIR HAS OIL IN IT - REPLACE OIL COOLER, AND SEALS". They specifically said it is the Engine Oil Cooler, not Transmission Oil Cooler.

So ask them how oil from the oil cooler gets into the coolant reservoir?


Then ask them how they ruled out either a blown head gasket and/or a crack in the block or head.

More confusion. I have spoken to a MB technician who said coolant does run into engine oil cooler, and there are seals to separate oil and coolant. If the seals or cooler go bad, oil can mix with coolant.

If the technician is right, it supports what the dealer found and recommended.

Attached are the pictures of the oil cooler on my car and signs of leak.

If you go back to post 2---you will see where I amended my post and apologized the confusion I caused---you and the tech are very correct

He is right.

Thanks for all the helps. Looks like the oil cooler p# "A 272 180 04 10" is what I need. Is "A 272 180 05 10" the same as "A 272 180 04 10"? Any DIY instructions?

http://www.mbpartsworld.com/p/Merced...721800510.html

The 272 180 05 10-----is the current part number and do not forget the gasket 272 184 02 80

The change out is very streight forward.:eek:

I'm having this exact problem with oil leak around oil cooler, can I just replace gasket?
Thanks

Any diy for this repair? All I found was for e55's

This is quite a common problem with the 272/273 motors. Replacing the seal alone will not fix the entire problem you have at this point. You will need to flush the cooling system to remove the oil from it. This is a time consuming process, but is fairly simple. The expansion tank should also be replaced as well. Tide detergent works quite well to remove the oil deposits.

Ok so I just replaced the gasket and those thoughts just ran through my mind oil change and flush. Thanks for your reply. Now how do I do the flush & when you say. Expansion tank must be replaced you mean coolant in their correct? I don't wanna sound far out there lol but that's where I added the coolant?
A diy on the flush and expansion tank will help a lot.
I'm gonna goto the dealer tomorrow to get coolant.

Is it too cold to do the flush and should I have the dealer do it?

You can do the flush yourself. The longer that there is oil in the rubber hoses. The more damage that will be done to them.

As I stated it is a very easy process, but takes time to do a thorough cleaning.

1) Drain the coolant
2) Mix one scoop of Tide detergent in to solution in a gallon of hot water
3) Fill the cooling system with the Tide mixture, and water.
4) Run the engine for 30-45 minutes
5) Drain the Tide mixture
6) Fill the cooling system with water
7) Run the engine for 20 minutes
8) Drain the water
9) Repeat steps 7/8 until water is clear
10) Severe cases will require the entire process to be repeated
11) Replace the expansion tank
12) Fill with 50/50 mixture of coolant, and water

I set up an appointment for tomorrow at the dealer for a flush. Cost is $144.99. It's in the single digits over here in va with a wind chill in the negative. I didn't think it be wise to run water in these temp's. Do you think they will flush the system good enough? And what is the reason to replace the expansion tank and cost?

The flush that they are doing at that price will not rid the system of all of the oil. The coolant expansion tank has many baffles in it. There is not a heavy enough flow rate to clean all of the oil deposits out of it. That is why you should replace the reservoir. You could also remove it, and use brake cleaner to clean it out if you wanted to.

There is hardly any sign of oil in the coolant other then a kinda sheen in the expansion tank. I will tell them why I'm flushing and ask them what kinda flush there doing

Ok so I'm at the dealer now and the SA just told me the tech suggested pulling the expansion tank and cleaning it out because just like you stated it wouldn't get all that oil out.
Total 230.00 and there using some BG product to flush it. Hey man you where def. on the money, not that I doubted you but it's way to cold for me to do it outside. Thanks so much for your advice and expertise!!
Oil change last night was a killer, could only get 3 quarts in at a time before having to get inside to warm my hands up.

I am sorry for reviving the thread, but I've got same issue with oil leaking through the gasket.

Question: is it necessary to replace the cooler as well? There is no oil that I can see in the expansion tank that I can see.

Question: Is the oil cooler known for going bad?

Very common problem. If you go to a dealer it's cheaper to replace the entire oil filter housing then just re-sealing. Which makes sense because more labor is involved if you re-seal vs just replacing. This is a very common problem with 272/273 motors. The early you fix it the better.

Thanks for the reply. I checked online it appears they've done away with a separate oil cooler and it's now coming as part of the oil filter/cooler housing (part no. 2721800510). Is it correct?

Dawn dishwashing detergent is a better surfactant for removing oil than Tide.