oil question (did 171/174 repair last night)

I did the valve cover, port clean, plenum clean last night. Took 3 hours start to finish. Took the cowl off and it was pretty easy. Just fyi, the plenum bolts and isolator bolts all get torqued to 89 in-lbs. Confirmed by Ford. Anyway, upon removing the valve cover right around where the oil fill hole is there was a really milky liquid, almost like vanilla pudding. The oil looks fine, what was beneath the valve cover was fine, no other obvious problems. It almost looked like if you took oil and mixed it with soap to create an emulsion. As I said this was only around where the oil fill hole is beneath the cap.

Any ideas?

Piper

Foamy oil is usually a sign of water somewhere in the system.

If it's a really small amount, it might just be the effect of occasional condensation inside a cold engine.

Any signs of rust or foam on the dipstick?

Hi Phil

No, there isn't rust or any other alarming things I can see. I live in Ontario Canada where it's common to have -10'C during the day and night. I've been doing a number of things on my van in a heated garage so maybe the warming (condensing of water) and cooling when outside again is doing this. I've never seen this before in my van or any other actually.

As I said, this was just around the fill hole and stuck to the inside of the valve cover. Probably a tablespoon in total. Everything else looks like nice new fresh oil.

I guess I'm praying that I don't have a coolant leak somewhere contaminating the oil.

Piper

I would suspect the fill cap is breathing a bit of air and moisture. Its interesting that a new filler cap o-ring is including in the engine gasket set. It should be available as a separate part.

I presume you're not noticing a loss of engine coolant.

Given no other symptoms, I'd suspect condensation. Warming/cooling cycles of anything that contains air can result in condensation - so it's likely been occuring even before spending time in the garage. You might look over the PCV system and make sure everything is flowing properly.

I did the valve cover, port clean, plenum clean last night. Took 3 hours start to finish. Took the cowl off and it was pretty easy. Just fyi, the plenum bolts and isolator bolts all get torqued to 89 in-lbs. Confirmed by Ford. Anyway, upon removing the valve cover right around where the oil fill hole is there was a really milky liquid, almost like vanilla pudding. The oil looks fine, what was beneath the valve cover was fine, no other obvious problems. It almost looked like if you took oil and mixed it with soap to create an emulsion. As I said this was only around where the oil fill hole is beneath the cap.

Any ideas?

Piper
You can replace the oil cap or you can try to replace the seal.. If you notice the cap is a snap type so it may have lost some of it sealing. Its sucking in air around the cap. No worries really.. When heat mixes with cool air at a fast rate it will cause moister to form.

I have a "catch can" installed in my PCV line.
During the cold weather months, I get a LOT of runny milky junk in my catch can.
This is with NO coolant loss.
During the warm weather months, I get very little...and it is a thick tar like consistancy.

So....based uppon what I am seeing, there is a lot of condensation in cold weather......which is why phil-l's advice to make sure that the PCV valve is sucking away is good advice.
The PCV system is supposed to draw that junk out of there.

You might try a new oil fill cap.....air is not supposed to enter at that point.
The air to replace what is drawn out by the PCV system comes in through the oil breather, which is mounted on the opposite valve cover from the PCV valve.
So, if your PCV valve is in the rear valve cover (older windstars like mine), then the breather will be in the front valve cover.
If the PCV valve is in the front valve cover (1999 and newer), then your breather will be in the back valve cover.

That said, steam rises.....and the oil fill cap is a high point.....so it might just be condensation of the steam.....and it does not take much to make a milky mess.

Short trip driving is particularly bad...as the motor does not get hot enough, for long enough to fully dry things out.