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**TBONE1964** · 11-29-2012, 11:59 PM

Maybe I can help a little.

PCV as in Crankcase Ventalation. As it imply's, vents the crankcase. Anything that rotates in an inclosed space surronded by oil builds pressure. This pressure needs a place to go or it will blow out seals and gaskets. That is the primary function of a PCV valve and the vacumn helps it by sucking it out of the crankcase and into the intake ports (in most cases) so it will burn off any gases that are in the oil. If you look at a rear end housing or any transmission, they are vented to relieve pressure build up and prevent seals from failing and blowing out.

Crankcase pressure and oil pressure have nothing at all to do with each other. The reason that PCV's were invented is because the old style down draft tubes would allow oil to leak and not only make a mess on the ground but had the potential to start fires.

11-29-2012, 11:59 PM	#63
TBONE1964 Cluster King Join Date: Nov 2012 Location: Junction City, OR Posts: 5,263	Re: 327 Not Breathing Right?!?! Maybe I can help a little. PCV as in Crankcase Ventalation. As it imply's, vents the crankcase. Anything that rotates in an inclosed space surronded by oil builds pressure. This pressure needs a place to go or it will blow out seals and gaskets. That is the primary function of a PCV valve and the vacumn helps it by sucking it out of the crankcase and into the intake ports (in most cases) so it will burn off any gases that are in the oil. If you look at a rear end housing or any transmission, they are vented to relieve pressure build up and prevent seals from failing and blowing out. Crankcase pressure and oil pressure have nothing at all to do with each other. The reason that PCV's were invented is because the old style down draft tubes would allow oil to leak and not only make a mess on the ground but had the potential to start fires.