Okay, so I know this is bad, but how bad. There is oil in the coolant resevior. Possible causes?

Is it an M104 engine? If so, it is probably a head gasket. Just went through it. Cost in the vicinity of $800 to $900.

Best guess->headgasket. What car??

__________________
Jeff Lawrence
1989 300e
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.

Yup, head gasket. But like Jeff said, what model car?

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2006 E350 w/ 155k miles (Daily Driver)

Previous:
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)

Okay, so I feel foolish. It is an 87 300E with a 103 engine.

That would be the head gasket, unless it is ATF, engine oil will be brown and cruddy. ATF (from the cooler in the radiator) is reddish and does not produce the cruddy, brown residue. Hope it's the latter.

__________________
Jeff Lawrence
1989 300e
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.

Better look into the headgasket or you'd be heading into other gaskets in no time ..

__________________
... Kerry

126 tailed by a 203, 129 leading the pack.

Are you getting coolant in the oil? You could check by loosening the oil drain bolt a little and see what drips out first, the coolant is heavier than oil and will be at the bottom of the oil pan.

Hi,

Do your self a favor, and take it to a good mechanic who can perform a "leak down test" on your motor. I have this engine as well, great motor. The mech will fill each of your cylinders with compressed air, through a special fitting at your spark plug. then by tracking where the air leaks to(ie, up into the valve train=seals, into coolant=head gasket, into oil sump=blown rings, etc.) he'll be able to tell you what's wrong.


Best of luck to you
Evan Lewis
1986 300E
140,000 miles