What's in my oil?

[Silver02ex]

I decided to do an oil change in my fiance's 2000 Mitsubishi Mirage. She has put almost 3K miles on it and it's been 3 months, since the last oil change which was done by Wal mart. When I pulled off the oil cap, on the bottom of the cap I saw a milky substance which looks like milkshake. It's a cream/tan color. My first thought was coolant got into the oil due to a bad head gasket. The car has 61,000 miles on it. The oil has been change every 3,000 miles since she got it with 30,000 miles. I went ahead and drain the oil. the oil that come out seems to be normal, dark brown/black color. After I pulled off the cap I looked into the oil fill hole and saw little bit of the same substance on the cams. Any idea what this could be? The car is not loosing any coolant, so the head gasket might be out of the question. The last oil used was Pennzoil 5w30 and a Super Tech filter. Later on I'll see if I can post a pic to give you guys a better idea.

 

[ediamiam]

Problem is typically a oil filler cap where gasket no longer provides a tight seal, and is allowing cool moist air. This is seen most often in winter, and infrequently in the warm winters. I have a 60's car that had this problem severely such that it always looked like a milkshake. I solved it by forming a gasket and giving the filler cap a much tighter seal.

 

[Shadohh]

Yeah, sounds right to me.


go get a new oil cap at pepboys or from mitsu. It will be the cheapest solution.

Keep an eye on it and get back to us.

 

[moribundman]

Or the kid at Wal-mart poured a cafe latte in there.

 

[T-Keith]

Some engine designs tend to accumulate condensation in the oil cap area, partly because this is often the coolest part of the system. The Mitsubishi 3.0 seams to have some problems with this, the Dodge 4.7 is the worst.

My guess is that you have too many short drives, so the water never has a chance to boil out completely.

 

[Dr. T]

Is the thermostat working properly?

 

[Speed racer]

I had the same concern last winter when it got really cold out.
My Cherokee dipstick had drops of water on it and milky oil; so me thinks i have a coolant leak.
I dumped the oil and inspected it;... just a few drops of clear water at the bottom of the pan.

I surmissed that when i park the jeep, water vapor condenses inside the cold exposed dipstick tube, and when i pull the stick out to check the oil, the dipstick scrapes up the witches brew coating inside the tube.
I posted this on a Jeep website and other people had the same results, (only when it got really cold out.)

 

[Silver02ex]

quote:

---

Originally posted by T-Keith:


My guess is that you have too many short drives, so the water never has a chance to boil out completely.

---

Exactly... She drive about 2 miles to work each trip, around 8 in the morning which is still pretty cold, she start the car up and drive off. So 4 miles round trip a day for 5 days a week.

 

[Silver02ex]

quote:

---

Originally posted by Dr. T:
Is the thermostat working properly?

---

I don't see any problem with the thermostat. I also just drain and refill the coolant about a month ago.

 

[GROUCHO MARX]

You can get an oil analysis for about ten bucks. Anything other than that is speculation, but the short drives theory seems most plausible.

 

[bowez]

If no sweet exhaust dont worry.
Had a similar concern with the H/G replacement on the I-6 300 I did after about a hour on constant driving all the milkshake went away.