PCV Valve 'buzzing'

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bigtooth

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Should my PCV valve be 'buzzing'? The check ball that's in it seems to vibrate back and forth and it appears to be causing a bit of a vacuum leak. When I manually plug the valve my o2 meter drops down almost a whole point richer, when I let it loose it jumps back up.

I read there are different PCV valves for different vacuum rates of an engine. How do you determine which one to use and what is the correct behavior of the valve?
 
As far as the meter reading my thoughts are when you plug it it is concentrating the vacuum to other areas.

I would spray it inside with some carb cleaner, WD 40 or equivalent and shake it up to help free up the ball. As long as the ball is still moving in it I would run it.
 
Oh yeah, the ball is free. That's what the buzzing is. At idle that valve is constantly opening and closing really fast. But that seems to be leading to the PCV valve pulling in enough 'air' to lean up the carb.. Not sure it this is correct or not..
 
Okay, maybe I should reword this :) What do you guys and girls run on your small block street cars for a PCV?
 
Is the crankcase breather restricted ? Is the PCV tube and port on the carb clear and tight ? I've had to clean a whole lot of those. If you're sure the air flow is all good, replace the valve.
 
I believe the breather on the opposite valve cover is good. I say this because I can pull the valve out of its valve cover and it still buzzes. The lines are tight. I'll try another valve, i'm thinking one with a lighter spring rate.. I wasn't sure if there was something specific to these or not.. thanks.
 
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