What causes a creamy, yellowish muck on the dipstick? I am terrified it is the head gasket, but I am hoping someone can give me a benign reason.

 

could be the cold weather and the oil not getting up to operating temp. my first year i had that problem.

 

I hate to be the bearer of bad news, but I've only ever seen that when coolant is involved. Better be safe rather than sorry and have it checked out now if you can't pressurize the coolant system yourself to check for leaks.

Continuing to drive like that could have serious repurcusions...

Sorry,
John

 

Do you have an Oil Catch Can installed? I had the same problem with my 04S. It had mayo on the dip stick and under the oil filler cap. Do you have mayo under the oil filler cap also? This began for me when temperatures dropped around and below freezing. As it turned our, the previous owner installed an OCC according to ALTA instructions which disables the positive crankcase ventilation system. The PCV is important in that it evacuates blow-by gasses, some of which are water vapor from the combustion process. Also, the air the engine ingests also contains water. It has to go somewhere. I rerouted the OCC to be between the PCV valve as input and connected the gray tube that leads to the base of the intake throttle body (high vacuum). to the OCC output. This cleared up my problem.
In any case, don't just assume that this is the problem and ignore it. It could be a leaky head gasket and ignoring it would destroy/damage your engine. Are you showing oil in your collant reservoir? If so, it is a head gasket. You may want to drain a bit of oil out to take a look. It might not be contaminated and the problem be isolated to your dipstick.

 

What causes it is moisture. WHERE it is tells more of the story. If oil itself is that color, that's bad news. If it's further up on the stick, could just be moisture condensing on the cold metal in winter, and not reaching a sufficient temp to burn off. Have you checked your oil fill cap? 'muck' has been reported there as well for the same reason.
Check your coolant overflow tank - make sure it is at the appropriate level. Then check it regularly. If the coolant level isn't changing, then the moisture is likely not coolant.

 

To be sure, take a sample and send it in for analysis. I use Blackstone or Dyson. They'll tell you if it's just water moisture or antifreeze.

 

This is in fact the most common reason. Check it out.

 

Drain the oil and look at it.

And I can't believe that a company would advocate disabling the crankcase vent system. That's inexcusable.

 

You don't say what year and model MINI you have. Put it in your signature so you don't have to remember to add it when you ask a question.

Get your car to a MINI mechanic, a bad head gasket isn't that expensive to fix, if you don't let it go too long.

Dave

 

If it is a MCS, then the heat exchanger for warming/cooling the oil might have sprung a leak. This is another point that oil and coolant come in close proximity.

 

Did you check it after a short trip? and How new is the oil and the brand?
My wife's X5 looks like that cause she only drives 3 blocks to work. Not enough time for the engine to fully warm up. I try and warm it up for her or take it for a drive one a week.

 

Hard to diagnose on the puter, but my guess is cold weather & short trips. That is a very hard use of any car. Change the oil & drive until the car is warmed up fully.

 

Milky oil is a sure sign of water, find the problem or you will have serious engine problems. I have an '02 MCS and only have a 2 mile commute to work in upstate NY so my engine doesn't fully warm up. Temperatures here have not been above freezing for ~ 6 weeks and when I checked my oil level last weekend my oil was clean, no white milky muck.

 

Well, I think it is from the cold weather and my short commute (4 mi). I took a long drive and have not seen the muck since. Thanks for everyones thoughts.

 

Well I am glad it's not a head gasket! Don't ya hate it when your Mini scares you like that? But short trips do cause condensation. I would take a longer route to work every other day. It takes an engine about 8 - 10 miles to reach full running temp, and also to blow the condensation out of the exhaust system! 4 miles might work if you were able to get up around 70 miles per hour, but in town driving just doesn't do it!

 

Do you have an oil catch can?

 

no, no oil catch can. Do you?

 

I've got an 05 MCS with an Alta catch can and its doing the same thing. I also take several short trips a week. It's not may daily driver. Does anyone have a diagram cybercg references for rerouting the lines? Mine has been installed for about a year and I just started noticing this. I have it at the end of my dipstick, under and around the oil cap fill area. I also put my finger under the valve cover opening and its there too. I am real concerned about it. I changed the oil and it looked normal. I also getting alot of moisture collecting in the can. I am considering taking it out and returning it to stock. This cant be good for the engine long term. Is it just an Alta product OCC thing or do other manufactures OCC's have similar issues? Any Alta factory guys care to weigh in on this subject?

 

The installation of the catch can can be the cause of the problem. I had mine installed as per the original Alta instructions, but found out soon after that it was not correct. The catch can needs to be installed on the high vacuum line coming from the passenger side of the valve cover and not to the low vacuum line on the other side or to both.

I ended up installing it like this one (minus the red lines and can).



The use of the catch can is safe as long as it is installed correctly, like dark one installed above. And it definitely keeps the crud from coating my IC, SC and intake tract.

 

IMO, that's just trading one problem for another. Unfortunately I'm very near the freeway, and watch the OPG on my other car (miata) go WAY up when hitting the freeway before a reasonable warmup period. So you may get up to op temperature, but in the warmup interval, you may be getting starved of some lubrication due to viscosity.
15-20 minutes is a good interval for full warmup and condensation burn off.