Condensation on oil fill cap of a 911 SC.

[Ken Wilson]

After a very mild winter in this part of Montana and more in town driving, I am finding evidence of moisture on my oil fill cap. All the hoses that have anything to do with oil and crankcase vapor seem secure. Is this a problem? Normally when I have put the car on the highway and let the left foot down, this disappears. 280 miles on Friday did not do much.

[Tyson Schmidt]

Very normal. It’ll take elevated oil temps to get rid of it all and that may be hard to do this time of year in your region.

[fanaudical]

How warm is the oil getting?

[mike sampsel]

Yes, short in town driving will increase the moisture from condensation. It’s a reason you want the occasional longer trip to get things warm enough to evaporate all the water.

[Ken Wilson]

It is great to get some reassurance. Love affair of 21 years and I want to keep her happy.

[MichaelSJackson]

You don't want to leave that condensation in there. Take her out for a longer drive. Get her hot. Then park her.

[jschmidt63]

I have the same issue here in central Oregon with my 84 3.2. I try to drive it hard a least once a week and long enough to get hot. Dont know if this helps but when I park in garage I pull the cap and let it vent for a while thinking it may release a little more moisture in the oil.

[911pcars]

That mayonnaise-consistency material is historically called sludge. It’s usually indicative of not bringing the engine up to operating temps often enough and/or not changing the oil often enough to rid the engine of that buildup. Excessive amounts can block oil passages and inhibit heat transfer.

It’s just some evidence there may be additional areas of that same buildup inside the engine.

The solution is to drive long enough to bring the entire lube system up to temp. before shutting down.

Sherwood

[manbridge 74]

Another solution for short trippers/cold weather guys is to block the grille off maybe 90%. Gets the thermostats opened up enough to send oil to the front cooler etc. Fab one up that’s quickly removed, the suction helps in holding it down.