Oil in Coolant
 

1990 300SE
Engine 103.981
126 Chassis

My coolant light came on and when I went to add the coolant I found a puddle of oil in my coolant tank. I also found that the radiator was leaking, possibly a hose, I couldnt tell, everything was oily. I have never noticed the engine overheating , but the low oil light has come on a few times and I filled the oil back up almost immediately (It has 2 major oil leaks).

I know this sounds like a head gasket or warped head, but please tell me it isn't. :o)

This is my only vehicle and college starts back in 2 days. Could someone please advise me on how I can still drive it (what can be done as a temp fix, such as draining coolant once a week) and the least expensive but lasting fix.

I am an OK shade-tree mechanic, but head work scares me. I have never pulled a head off of any vehicle, let alone a mercedes.

Selling the car is really not an option because I have already spent about 1500 dollars on other parts and I just feel I wouldnt be able to get that much for it.

Thanks in advance

Michael

Sorry man, thats a tough situation. It does sound like a head gasket problem. Unfortunately driving the car will only make it worse and there are no quick easy fixes for head gaskets.

Is it smoking from the exhaust at all? Sometimes you'll see white smoke from the exhaust if coolant is getting into the cylinder.

You could try loosening and re-torquing (has to be to the correct torque) the head. It's possible one of the head bolts has backed off allowing the head gasket to go slack in one area. That's pretty unlikely though.

No smoke at all is seen from the exhaust. I dont even know how to tell if it is the gasket or if it is a warped head. Am i supposed to pull the head and take it somewhere so they can check for warpage?

Don't worry, or do anything, unless the oil pushes out of the top of the tank.

Park it, or make it worse
 

What in BH does that mean??

A partially blown gasket doesn't necessarily blow white smoke, meaning burning coolant. Sometimes the gasket can go such that oil just gets into a coolant channel first. No way to know if the head is warped until it comes off to replace the head gasket. Unlike that advice from Chas H, the longer you wait and drive it, the more likely you will warp the head. I say, park it and wait until you can fix it. Check the DIY article for head gasket replacement, and use the search field to find threads about what you, or a mechanic, need to do.

ditto above,
 

Hey Mike. It would seem you are at crossroads with the car. Factor in a head gasket with a new timing chain/rails too. Might as well do that too if you got it apart. The final will be a running car that will have most of the bugs rectified.Not a hard job if you take your time and pre read some info and search this and other forums. Or...take a loss and sell it for what you can get.

Thanks for the advice. I noticed fastlane didn't list a head gasket for my model. Maybe Phil can get me one from somewhere.

You're right, I am at a crossroads, but I love this car so I guess it just became a project car. I will buy me a little Honda to keep me going.

Does no one pull the plugs and observe their condition, do a compression test and then pressure test the coolant system before recommending jerking a head off of a 17 y/o engine when a little oil appears?

I will try to get those things done tomorrow and report back. What are we looking for (or hoping for, in my case)?

You need to replace the head gasket and when you do that, you should also replace all radiator hoses, do a cooling system flush and replace the coolant. Hoses contaminated with oil are very dificult to clean and the oil will attack the rubber and those hoses will start to leak shortly.

Juan - In addition to replacing the hoses, I was wondering what could be used as a flush to rid the cooling system of the oily residue. Perhaps a little dawn detergent mixed in with PLAIN water and run for a few minutes should get the oily residue out? Rinsing the system out several times afterwards to get the soap out, of course. :)

Thanks for the advice, keep it coming, please.

Are you sure its OIL and not ATF?
 

Remember that the ATF cooler is in the radiator (end tank) and I have seen many a rad tank cooler fail and look like a head gasket failure...

For cleaning the cooling system, the MB Degreaser works best but SHOUT works just as well and is easier to get at the big box/sams club stores.

That mayo is really hard to remove. I used a comercial degreaser and some laundry detergent mixed with tap water and flushed the system several times. I did that like 4 times the same day and let the car running with tap water for a week. Then I repeated the procedure and added coolant. After a month I started to get leaks in some hoses, so I replaced all hoses and changed the coolant again. I don't know if there is a better product for that. That's only what I did but don't know if that's the best option.

What is going on with these MB head gaskets. My bypass hose burst last night when I got home...no big deal I thought, I'll just get new hoses today, some coolant, and fix it.
Well, there was a lot of oil in the coolant when I removed the lower radiator hose. I've never had to add oil to between oil changes since new, and sure enough, it is about 3/4 quart low on oil.
The car just turned to 88,000 miles and runs great, but no sense installing $140 in new hoses on the car if they are going to get saturated with oil. So I guess I'll start removing the head on Monday and see if the head gasket is blown, or the head is messed up or warped.

My friend drove at least 40K miles with oil in his coolant on his 190E with a 2.6 engine. He would occasionally pump out some of the gunk from his reservoir and add fresh coolant, but it didn't blowup or anything. He finally did do the head gasket, but it really did go for an amazingly long time with no real problem. He drove back and forth from NJ to PA and regularly drove at 100+ mph, so what the heck does it matter I guess. He puts on so many miles that it happened over a relatively short period of time. I know my head gasket leaks and the front timing cover too, but I am waiting until I see oil in the coolant and even then I may still wait a couple of years, since I only drive about 10K miles per year. I have had a leak for 2 years or more and so far no problems. I wonder if you should really ever fix anything on these cars, unless it absolutely won't start or go or something. Just drive the thing until it dies and then buy a Honda.