I took off the oil cap today and there is air pressure comming out of the crankcase. I just rebulit the engine because it was smoiking BIG TIME. All the smoke is gone now, but there is that damn air pressure now. Is this normal?

 

First make sure the PCV valve and PCV hoses are clear and working correctly. If PCV system is unable to pull a vacuum in the crankcase at idle and you have positive pressure, then you have excessive blowby one of the pistons.

good luck

 

It is 100% normal, when the vehicle is running, and you take the oil cap off, you will feel and hear air coming out.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Petekazel &raquo;</TD></TR><TR><TD CLASS="quote">... I just rebulit the engine because it was smoiking BIG TIME...</TD></TR></TABLE>Isn't it sorta normal to have more blowby until the new rings are seated?

Yes, make sure the PCV system is OK.

Even then, you get air puffing in and out as the pistons move. That feels like it's blowing out, even when it's going equally both ways.

 

If PCV system cannot maintain negative pressure at idle, then blowby is excessive. Crankcase pressure does go positive during heavy acceleration when vacuum is low and blowby higher, but not during steady speed or idle.

good luck