Hello,
I suspect that I have high crankcase pressure in my '94 940 ('88 240 engine) because smoke and oil comes out of the dipstick when it is removed and the car is running at idle, and increases as I give the car throttle. Also, my metal oil cap (from an older volvo) also vibrates when loosened as per the FAQ. Feeling with my hand over the oil fill hole, there may be a very minimal amount of vacuum. I can not feel any vacuum over the dipstick tube when I remove the dipstick and cover it with my finger.

I just finished cleaning everything from the oil seperator ('breather box') all the way to the brass nipple on the intake with no change in the above symptoms.

No other oil leaks (yet?)

Any ideas?

Thanks!

I cleaned my oil separator in an attempt to correct a crankcase pressure problem without success. I ended up installing a new one and got vacuum at the oil fill cap - not much vacuum though - best way to test may be with your hand in a latex glove. Check the archives on this one as there's lots of related comments. You may need a new O ring seal on the dipstick.

Ron
93 245

In rare cases the oil separator itself can become clogged. You can remove the oil filler cap and see if you can blow air down through the breather hose. It sounds as though you just have a bunch of blow-by.

I have already thoroughly cleaned the separator. Any other ideas?

Also, you do not need to drain the oil to clean out the whole system.

Thanks again!

Does the oil need to be drained to do this?