Macster

New still in the original bottle engine oils have very low amounts of water. Even opened the oil does not attract or retain moisture like brake fluid which has an attraction for moisture.

(Note this may not be the case for other bottled engine oil or fuel additives. I used to own a diesel and would buy and add a diesel fuel additive once in a while to my car's fuel tank. I'd open the bottle, remove the foil seal, and pour the stuff into the fuel tank all but a quarter of a cup. Sometimes at the bottom there would be a small pea sized blob of water/gunk rolling around in the remaining fuel addtiive.)

AFAIK all modern engine oils have the same very low affinity for moisture.

The seal at the oil filler tube should be very good or that's a vacuum leak.

The real problem is that water vapor gets into the oil as a by product of combustion. The upper reaches of the oil filler tube are relatively cool compared to other areas so when engine is hot and the crankcase vapors are laden with water vapor then when you shut off the engine the fumes in the oil filler tube cool down very rapidly and the water condenses out on the colder surfaces where it mixes with the slight amount of oil that has collected there and the slightly discolored butter or thick cream-like stuff appears.

That this is present suggests several things: 1) The engine is not being run long enough and gotten hot enough to heat the oil up high enough to boil the water out of the oil. 2) Because of (1) the engine oil should be changed more often to keep the build up of water in the oil down.

As long as there are no water droplets on the dipstick, no smell of antifreeze in the exhaust and the coolant tank remains free of any signs of oil and there are are no other signs of engine distress -- oil and coolant levels remain constact or do not show signs of drastic drops in their levels -- the presence of that creamy junk in the oil filler tube around the bottom of the cap and at the uppermost reaches of the tube is normal.

Sincerely,

Macster.

Pac996

Hmmmm no problem here in Hawaii. My advice is walk outside barefoot in shorts and t-shirt and take stock in what you are doing to yourself and family besides your cars.

redridge

there is a huge differential temp in the engine and that filler tube..... That tube is long! Moisture is bound to be in that tube.

Pac996

Maybe try insulating the tube.
Better to have condensation high and on plastic than on metal parts.

Macster

The condensation is actually conveying some good info to the owner of the car. It is an indication of just how much moisture is present in the car's oil.

The solutiion is not to insulate the tube to avoid the condensation but to change the oil/filter more often to drain the oil with the water out of the engine and replace it with fresh water free oil.

Water in oil lowers the oil's viscosity and the last thing these engines need is lower viscosity oil.

Sincerely,

Macster.

GNR996

thank you sir, finally, something that says water in the oil is not such a good thing.
I tend to believe it is a function of the oil used, just by observation, trial and error.
When I ran oil XXX no matter the driving habits the gunk was present, switch oil no gunk.
It may be "normal" but I can't believe it's harmless over the long term.

yasuro

i'll have to think about this.

i change oil every 6 months or 2500 miles, whichever comes first, and i have gunk in the filler tube in winter. so i'm not sure if i should be changing more often or that the cause of the gunk is not indicative of water in the oil. there's always going to be a bit from the moisture in the air in the filler tube, but is that enough to form the gunk?

i'm still unsure.

Tippy

Guys, what you are seeing is not condensation emulsifying with the oil, it is the grease inside your IMS bearing that has finally leaked out causing a reaction.

This is the first sign of an immenent IMS failure.....!!!!!!!!!!!


Relax......just kiddin'

Sorry, I had to do it!

As others said, the tube is a great ways away from the engine where it is cool which allows oil vapor to mix with condensation creating a nice, buttery goodness.

Dennis C

Any good suggestions on a good way to clean the filler tube? Should it be removed, or should I just try to reach down through the opening and scoop out the gunk?

BruceP

I don't get this gunk, for some reason. My car frequently gets driven very short distances from a cold start in the winter, and I use The Oil That Dares Not Speak Its Name. About the only difference between me an some others here that I can see is that my car is parked underground at both ends of my commute.

Will follow with interest.

Dave!

microfiber towel + finger = success!

gota911

Try a milk shake straw, but don't swallow!

Hell, I know a few women who......... well, never mind!

joelpirela

If you have a small crack on the filler tube, humidity will be creeping in and condensation/moisture may occur... ergo the gunk. even if the cap is tight.

Macster

It is normal absent any other sources of water in the oil like a cracked block, head, leaking gasket, or possibly a leaking oil/water cooler. Also, that this gunk's presence gets mentioned in various buyer guides for water cooled Porsches, at least in those buyer guides published in UK car mags, suggests it is rather common and normal.

Being normal however doesn't mean it is not harmless, or at least does not present some increased risk of harm to the engine.

As I mentioned, water in oil lower's the oil's viscosity and the last thing these engines need is lower viscosity oil.

I'm sure that when you changed the oil the gunk was absent afterwards. Draining the oil of course removes the water along with the old oil.

However, absence of any gunk afterwards is probably due to a change in climate conditions -- and I believe your claim you made no change in driving style -- and less attributable to the differences in the old oil vs. the new oil.

I've seen this gunk, but thankfully not that much, on my Turbo's oil cap and around the oil filler tube opening, but after wiping it away it has not returned.

Being I had just recently -- last June -- bought the car I checked for gunk regularly cause if there's a problem I want to identify it while car is still under CPO warranty. It has not reappeared and while I have changed the oil several times, once or twice using Mobil 1 0w-40 and then switching to Mobil 1 0W-40 and the last oil service switching to Castrol Syntec 5w-50, I do not believe the differences in oil viscosity or even brands accounts for the absence, only that I'm driving the car more often and now that I'm more comfortable with the car driving it longer distances and driving the car a bit more aggressively than when I first got it.

Sincerely,

Macster.

Pac996

Just move to Hawaii and forget about that crud