1963 Olds 394 PCV operation

Trying to figure out how it was intended to work. I far as I can tell vaccum pulls up the metal disk in the valve to allow crank case to vent up large hose to air cleaner snorkle. What is wierd is when vaccum is connected to it it just sucks the crank vapor into the vac line to carb base. Makes for a vac leak and unfiltered crank vapor to be sucked into engine. I have installed a new valve and still the same way. As best I can find the vac line is the correct one from carb base.

 

Fresh air is drawn from the air cleaner housing into the crankcase, and pulled out through the PVC valve into the carb base or intake manifold.

What you describe is normal. The carb does react to it the same as a vacuum leak, and has to be calibrated to compensate for it. So, a PVC system needs a carb set up for PVC.

I'm thinking that a '63 Olds with PVC from factory would be California only. If so, carb replacement would need to correspond.

 

63 was I believe the first year for the olds PCV on all models not just CA. The beginnings of the &#8220;Green&#8221; movement. <?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>

 

I'm not familiar with the specifics of a 63 Olds but the first generations of the PCV system did suck oil vapors and water vapors into the intake below the carb. There should be another breather probably on the oil fill tube or the valve cover to let fresh air in. Th closed system with the tie in to the air cleaner came along a little later. There is an ass load of threads on PCV systems on the HAMB.

One thing to remember is the valve is made so that less air is passed when the vacuum is high. (idling) As the load is increased, the vacuum drops and the vale allows more air to pass when it is needed more. Just backwards from what one might think. A search will keep you reading for hours if you want. Most of the misconceptions get eliminated there.

 

Thanks. I do know a bit of the concept and read some new info with a search.

Still.... the way this is factory set up does not make sense. It draws air into the crank case from the oil fill cap that does not have a filter in it. It then sucks from the PCV valve directly to carb base. The PCV then has a hose up to the air cleaner snorkle (outside of the air filter). A first look I would think the vac would just open the valve (and not continue to suck) to allow vapor to travel into the snorkle then pass through air filter into carb.