bebbetufs

Recently there has been a thin layer of condesation foam forming on my oil filler cap. Bright white, looks like steamed milk. I have also lost a little coolant, but I recently drained the system so this loss may be down to air pockets in the system. Did one 600miles round trip and one track day and the coolant only dropped an inch below the max mark.

The condensation did burn off on the way to the track, but on the return trip, when it was raining cats and dogs I found condensation trails on the cap when I checked the oil mid jurney.

I drained the oil and found no traces of coolant. There are no traces on the dipstick and no oil in coolant.

Oil cooler seals are almost brand new, but HG is probably as old as the car.
Should I suspect a fault or put it down to the climate (humid) ?

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1990 Turbo. 63K miles. M030, Dual Port Waste Gate, Upstroke and Downstroke Crank Scrapers.

Yarf

You could have the coolant system pressure tested.

bebbetufs

Is this something I can do myself?

John_AZ

In the states, most auto parts shops will have one to share free with a deposit.
Coolant pressure tester.
It will locate pin hole leaks in the cooling system. Use only about 10 or 12 pounds of pressure to test--not max or you may cause more leaks.

I would do a leak down test. A guage is required. I got mine at Harbor Freight tools for about $40 US
http://www.dietersmotorsports.com/Co...akdowntest.htm

This will test the head gasket.

Check your spark plugs. If you have one that is "steam cleaned" you may have a bad head gasket that is allowing coolant in the cylinders.

GL
John

M758

Older stock headgaskets can corrode and simply fall apart. Not much you can do other than replace it. I have seen many 944 heads that once pulled need corrosion holes welded up. Useally a leaking headgasket has 3 signs.
1) disappearing coolant.
2) higher water temps
3) unquie combustion smell in coolant reservior.

Of then car will run fine in cooler weather or lower rpm's. Get on it hard and that is when things happen.
Most of the time when seals go out you get oil in the coolant before you get coolant in the oil. The reason is oil is under higher pressure than coolant.

bebbetufs

From your replies I gather that you all believe this to be a real problem and not ordinary condensation which I was hoping you would say it is If this is a problem, would it be foolhardy to pretend I haven't seen it til after the upcoming DE?

Could this be related to the unnerving shut-down I had on the track?

M758

Probably not. You can pop a headgakset on car and it will overheat and dump coolant out the tail pipe.

At little condensation on the filer cap is normal. It happens simply from moisture in the air and most of the time a nice long run will burn it off.

I have seen many 944 that exhibit "mystery" coolant loss and over heating at speed on track that a sign of a failing head gasket. Most of the time condnesation on the oil cap is no big deal and is normal. However oil in the coolant is bad news. Could oil cooler seals or head gasket. This where you can sniff the expansion tank. What happens is combustion pressure forces gases in to the coolant system and this has a unique smell.

kombatrok

I have condensation in the cap all the time... Its pretty humid where I live. No big deal at all

Dawgz83948

Condensation on oil cap is normal. I get some an I live in California where it's not extremely humid.

bebbetufs

Checked today, absolutely nothing there. I gather this is yet another case of "the worry till you drop" syndrome Back to concentrating on the real problem mentioned in the other thread.

ZW 944

Yup, like others have said, its from humidity, switching to synthetic oil will relieve you of this problem. not sure quite why, but thats what I ended up doing on both my cars which had this problem, and I havn't had any trouble since.