On Sat, 30 Jun 2007 14:55:09 -0400, "Stormin Mormon"
wrote:

The crankcase breathers I've seen allow air out of the crankcase
when the piston goes "down", or into the crankcase. When the
piston goes up, the valve closes. This maintains a very slight
negative pressure, and helps cut down on oil leakage.

Not a pro here, but I've always thought of the breather as the direct
method for un-spent/burnt gases to escape. During the intake air we
don't want exhaust fumes to enter the head.

A clogged breather can prevent the escape of the gases and not vent
the block.


--
Oren

"I don't have anything against work. I just figure, why deprive somebody who really loves it."