Moisture on dipstick?

I keep finding nasty milky oil on the dip stick usually up around the top. I recently replaced the head gasket just to be safe because I have already lost one engine due to a blown head gasket.



I check and change the oil very frequently so that I can keep an eye on it but the oil in the pan allways seems to be fine. I change it so often that it is usually still clear. I even pulled the dip stick tube after the head gasket replacement and cleaned it out but a week later the moisture came back.



Any ideas on where this moisture is coming from? Should I even be worried about it since the oil in the pan is clean?



The guys at the parts store said that if the oil in the pan is clean then don’t worry about it… lol but I can’t help it, I guess I’m a worrier!

If you’re doing exclusively short trips the emulsification is pretty much unavoidable in some engines. You produce 1.4 gallons of water for every gallon of gas that you burn. That moisture is part of the composite blow by that seeps past your rings. If the engine is too cold to keep that moisture in vapor form, it condenses. Eventually it forms that crud you see.

There’s not much to be done about it. Now if it was due to your head gasket repair not working out quite right, that’s another story.

I’d do a UOA (used oil analysis) to assure myself that no coolant was present in the oil.

Edit: I just caught the tag “jeep grand cherokee”. Does this have a 4.0 in it? If so, I’m surprised that there was a HG problem. There were certain castings of the head that had flaws in the casting on the top side. It required an epoxy fix.

Did you mean you are “not” surprised? lol

The thing about the flaws does NOT surprise me… I’d never actually heard that, but I had heard that these engines are notorious for HG leaks.

Is this something I could have detected when I cleaned the mating surfaces? Because I cleaned them with a razor blade and alcohol. Very thorough job if I do say so myself!

I did not have a scraper tool just a box knife blade in my bare hand so I would have thought that I would have noticed it if it was easily detectable. I did not notice any major imperfections on either surface.

The 4.0 is basically bulletproof. As long as you don’t over heat it too many times, the head gasket should be good for a lifetime.

The casting flaw is on the valve rocker side of the head (the “top”). The casting number is 0331, iirc.

Look here or google images for jeep 0331 crack http://img261.imageshack.us/img261/2694/photo00083outline.jpg

What you are seeing in NORMAL when the weather is very cold. Make sure your PCV system is clean and working properly…

Thanks guys the info is greatly appreciated!

Replace your thermostat for a higher temperature range one. That usually fixes the problem. The 4.0 is one of the best engines ever built.

Take it out on the highway and let it get good and hot. That should get rid of any condensation in the crankcase. It’s normal to see this on some engines at the top of the dipstick or under the oil cap in cold weather on a car that only is used for short trips. You might check your PCV system to make sure it’s working right though.