When changing the oil today, the tech showed me how foamy the oil was just inside the filler tube.

I've feared a coolant seal problem for a while, but is there anything else that would cause the oil & water issue?

Thanks

 

Well, is coolant disappearing from the filler neck? What made you fear a coolant seal failure?

David

 

Baby poop brown? Pretty common here in the midwest with big temp swings in the spring and fall. It's emulsified moisture in the oil. Made worse from short trips where the engine doesn't get to full operating temp...or doesn't stay at temp for very long.

 

Yep, you just made oleo/margarine. You need to take your car out for a nice long ride and get it good and hot to boil off the water.

 

I can verify that foamy oil has lead to a blown engine at least once. My engine seals, i dont know which, leaked and mixed my peanut butter with my chocolate... Needless to say, my Reese's cup tasted like a blown engine.

 

last time i change my oil in my rx8 and it came out foamy and had a penutbutter tint to it was because i got a bad rebuild and it was cracked............

 

Car is almost always "short trips". Why would that cause the foamy problem?

Not using coolant, but then mileage is always fairly short. We do have the white smoke on cold start, but only first time in the am.

 

Because you get condensation inside the engine. If you do not get the engine temp up high enough and long enough to boil off the water...the water will mingle with the oil vapor and turn to oleo. Kinda the same way Velvetta cheese is made. The shorter the trips, the more humid it is and the longer it sits betweenst drives the more you will see of the foamy build up. It's normal under those type conditions. You can even get it if you drive a lot in a humid environment...like Florida. I used to see this in my old 1962 VW Bug all the time since I live near the beach. No "fluid" to leak into the engine either ;-)

 

I have to second the condensation deal. And if you use PENNZOIL (God forbid) it seems to be the worst about retaining moisture.

And the 'white smoke' at start up is likely just condensation too...very common and expected with ALL engines.

Short trips are the #1 killer of exhaust systems, too. Short trips just are NOT good for cars. This is why you will hear a lot of old-timers (like myself) say, "I'd rather buy a used car with 100,000 HIGHWAY miles over a car with 10,000 miles driven only to the grocery store..."

 

Hope the Short Trips are the real culprit.

Is a coolant pressure test the best way to know on the coolant seals? If so, is there a target reading or range that I should be looking for.

Thanks

 

Don't drive yourself crazy on this. If you are not losing any coolant, you don't have a problem. However, doing a cooling system pressure test can help diagnose/prevent incipient problems before they are serious, so that's not a bad idea, in any case.

On the subject of foamy oil in the filler tube, IMO, that's totally normal, and short trips in cool/cold weather are the worst, as the previous posters have said. If the oil you drain at an oil change is milky, THEN you have a problem.

 

You are over thinking it, if you arent losing coolant then dont waste your time on the coolant test.

 

As another old-timer, I agree 100%! That's why I have a beater (daily driver) that I don't worry about for those.