blow by

[Big Boys Toy PE857]

468 BBC Small Weiand 144 supercharger
Running perfectly
Why is the dipstick pushing out of its tube and spraying oil in the engine compartment? When you run the engine above 3000 RPM.
Don't tell me its ring blow by cause thats not what I want to hear. Want to make it through the end of summer without a rebuild.
Anything else I might check? What about removing the dipstick and putting a rubber plug and small clamp to keep the oil in the motor. Will it find another escape route?
T/Y

[superdave013]

tell us about your breather set up.

[Bob Hostetter]

Sounds like you don't have enough breather capacity. How many breathers do you have in the valve covers?

[Big Boys Toy PE857]

There is a breather in each valve cover that leads up to the bottom of the air filter plate. The air filter set up is one of those larger rectangular with rounded ends billet looking types. It has a large K&N filter. Single carb set up. I will try to take some pics, and see if I can post them.

[Snowboat]

Is it the same dipstick and tube as before, or is it too long? Do a compression check.

[Big Boys Toy PE857]

Everything on the motor is the same. It has just started this year pushing out the dipstick and throwing out oil. In a days time maybe as much as 2 qts. Guess I will do a compression check. It needs spark plugs anyway, haven't been changed in a couple of years. Only thing the motor runs as well as always. Guess it's like me, starting to get old and tired.

[Dave C]

do a leak down if compression reveals nothing.
I always ran a PCV to get a little pull on the crankcase blow by. Seemed to work for me.

[RACER52]

mine is doing the same thing. I know it has to do with too small of breathers or lack there of. I have 1 -20 an fitting in each valve cover going to remote kn filters. not enough though any hard runs to 6000 oil is everywhere. Also was blowing the dipststick out. Tempory fix has been to zip tie the dipstick and raise the lines to my breathers but still spews out.
Soon will put a puke tank like I should have to begin with.
I believe with a pcv valve and hose to the flame arrestors and the puke tank there wont be any problems.
Racer