Oil in coolant- oh noes! - United Bimmer Community

**Dudesky** · 06-17-2006, 09:24 AM

Sh**. F**k. Damn. Sunufabiatch. I opened the cap on the reserve tank, and this is what I found . .

Thing is, I don't know what the hell to think. Oil in the cooling system without other noticeable symptoms is really odd to me. The oil dipstick, filler hole, and cap check out okay. No noticeable loss of power from engine, no funky smells, and the exhaust looks normal; no smoke, no discoloration at the muffler tips. No leaks on or near the engine block. Other than the oil in the coolant, there's nothing to indicate a possible head gasket problem.

Or maybe not yet? I don't know too much about the AC system; could this oil be coming from that? I pulled some fluid out onto a paper towel, and the oil is brown, definitely looks like engine oil. I did some searching, but I only found articles about coolant in the oil, not the other way around . . any thoughts or suggestions, other than riddling this stupid car with bullet holes?

witeshark · 06-17-2006, 10:52 AM

Looks like engine oil to me. In my car the cause was a cracked cylinder head but there was coolant in the bottom of the oil pan. Hope yours is an easy fix

Storamin · 06-17-2006, 10:56 AM

My thought would be the headgasket. You don't have to overheat with a weak headgasket I thought. The headgasket on these cars are probably one of the weakest links. IIRC you do have quite a few mles and had a problem with the cooling system a little while ago didn't you?

**Dudesky** · 06-17-2006, 11:04 AM

^^^Yep, 148k on the clock. The cooling system overheated about 6-7wks ago, radiator was replaced, coolant flushed & refilled. That may have weakened the head gasket. But why would there be no signs of coolant contamination in the oil??

**c1apton** · 06-17-2006, 08:20 PM

D-sky - that could be the lubricant some aftermarket radiator mfgrs coat the internals with. I'ld do the "bars leaks" treatment just as insurance and then watch it for awhile. Head gaskets can leak both directions oil to water / water to oil but if you do the "HD bars leak" it might prevent the head gasket from letting go if it was weakened from your earlier experience.

**Rob** · 06-17-2006, 08:54 PM

Yup. I agree with clapton on the matter. I had the same stuff in mine before I did the radiator swap. I flushed it all and the coolant looked to be in decent shape. After the new radiator and flush, I have yet to see it come back, but then again, my coolant is purple from the Water Wetter.

I don't think you have any issues, so you should be fine. Just keep watching it.

Rooz · 06-17-2006, 11:52 PM

Question before you freak out, did you ever us some "Red Line Water Wetter:?

**Dudesky** · 06-18-2006, 12:01 AM

^^^Yes, I have the fan delete mod. And thanks, c1apton and Rob . . I stopped worrying so much about it for a few hours today, and yes, the same thoughts hit me . . could be anti-corrosion coating from the new radiator. I also took samples of the oil in the coolant against an oil sample off the dipstick, and the color wasn't exactly the same. I also opened up the oil filter canister to make sure I didn't have coolant mixed in. Then something else hit me- Water Wetter tends to look like droplets of oil, particularly when using non-BMW brand coolant; I use Zerex GO-5. I take it that's where you were going with that question, Rooz? I'm thinking it's gotta be one of those two answers, so I'm not gonna sweat it until & unless I start seeing other symptoms.

Oh yea, c1apton, I did the Bar's Leaks thing back when the radiator was replaced, as per your suggestion

Now I'm gonna get back to the original reason why I went under the hood this morning- to check the belt tensioners . . I'm getting a little whine coinciding w/ the rpms, I figure the bearings are going on something down there. If not one thing, it's another

witeshark · 06-18-2006, 12:11 AM

Sweet - what a relief! I bet that's it

**alanaszkler** · 11-15-2007, 11:37 AM

1992 535i Dinan has a milky oily coolant but no sign of water in the dipstick.
Never overheated, does not have any adverse performance issues and has been running fine all year. In the repair shop for a coolant flush and fill.

Any opther suggestions prior to replacing the head gasket?

**xxxbimmer** · 11-16-2007, 07:08 PM

ehhhhh good luck with the fix guys........one of the worst things to see