Engine: Oil spray from dipstick tube

[pdrnec]

Anybody have any idea what would cause an oil leak from the dipstick tube? I lost a quart of oil on a trip from LA to Vegas Saturday, sprayed all over the passenger side inner fender. I wrapped a rag around the dipstick where it goes into the tube on the return trip, it was soaked when I got home.

[Son O Lark]

Vent tube blocked?

[doug]

Isf your car still has a PCV valve, clean it or replace it. If this problem popped up suddenly, that could be the problem. Do you have a vented oil filler cap, clean it too. Too much pressure in crankcase due to blow-by of the rings.

[kamzack]

Somethig's blocked. Engine has to release pressures/breath somewhere.
Hope this helps,
Kim

[pdrnec]

New valve cover breather caps, has a pcv valve - will try replacing that. Engine has 3K miles on it, if it has blow-by i'll be seriously bummed.

[Mike Van Veghten]

8000rpm, long distance cruise rpm will do that to ya...

Yea...sounds like not enough ventilation for the blow-by produced. Anywhere from a plugged crankcase system to excessive blow-by.

Mike

P.s. - Just read your last post...rocker cover breathers AND a PCV valve...!? I'd have to think on what that combination would really do...?

[41 Frank]

Studebaker started using one breather cap per valve cover and a pcv valve in '63. California vehicles I have no idea.

[JoeHall]

When did the misting start, i.e. immediately after rebuild, or later?
What is the final drive ratio?
Under what conditions is it worst?
What kind, brand & weight oil are you running in it?

Barring an incorrectly installed PCV (backward), it sounds like the rings are still seating. My rebuild took about 6000-8000 miles for the (chrome) rings to seat, and stop misting (as yours does now) under high load/low vacuum/high RPM conditions. Now, at around 13000+ miles, all is well, even with synthetic oil, and it is getting phenomenal oil mileage, also.

Moly rings seat much quicker, as do cast rings, but at 3000 miles they may still be seating. Try 10W30 dino oil, and avoid prolonged RPM above 2500 for a few thousand miles.

[pdrnec]

Good points - I ran 30w dino oil for 1000 miles to break it in, then wen to 10w30 synthetic. It is only noticeable on the highway - high load, low vacuum as you said. It turns about 3200RPM cruising at 70 - 75

I think I'll go back to dino oil for a few thousand more.

[JoeHall]

Good points - I ran 30w dino oil for 1000 miles to break it in, then wen to 10w30 synthetic. It is only noticeable on the highway - high load, low vacuum as you said. It turns about 3200RPM cruising at 70 - 75

I think I'll go back to dino oil for a few thousand more.

Pat,
That is the first thing I'd do. I did not mention it earlier, but had to go back to dino oil, after swapping to synthetic in the above car when it only had a couple thousand miles on the rebuild. Tried the synthetic about 5000-6000 miles later and all was well.

OTOH, your and my experiences just proves synthetic is good stuff, even too good to seat the rings. Slicker than snot on a door knob