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After reading a number of posts on the subject, I decided to try disconnecting the PCV from the carb to see if it would reduce my engine's smoking. I plugged off the carb vacuum port and ran a tube from the PCV valve down to under tha car. Seems to have worked! At idle and easy driving, I see nary a whiff of smoke. When I romp on it, I still get smoke. I'm suspecting bad valve guide seals, but I want to put off any major engine work till at least next winter.

Soooo ... am I risking any kind of damage by running my PCV open like this? Any reason why I shouldn't just keep it this way?
 

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The PCv system helps remove contaminents from the crankcase,ie,water and gas.Pre-PCV cars used road draft tubes comming directly from the engine valley and an 1 1/2"+/- in diamiter.Oil was also changed at frequent intervals.My recomendation would be to use the PCV system and a heavyer wight oil.
 

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If you continue to run the PCV in a down-draft mode, remove the PCV valve itself. It needs the vacuum from the carb to open up. Without it, it will not act as a downdraft tube.
 

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Concur with Midlife; run baffled breathers or install hose nipple in PCV grommet instead of PCV valve and run hose to remote location.

IMO, a properly functioning PCV system should reduce oil contaminating the combustion cycle as it assists in promoting ring seal. If the baffling is incorrect, especially with high blow-by, rocker gallery oil may be sucked into the PCV hose and then into the engine, where it is burned. What's going on with the other valve cover...?? Any breather/cap/hose thingie over there?

I don't run PCV on the race car but instead use baffled valve cover caps which connect via hose to a remote puke tank which filters the vapors and catches any oil for later drainage. As I use a total seal gapless ring package, blow-by is very minimal but there will always be some. Although an engine driven vacuum pump or header mounted vacuum generator might be better for my application, I chose to keep things simple...so far, no adverse effects.

BTW, burning oil under power (accelerating) is usually caused by bad ring seal and/or failed oil rings. Burning on decelleration often comes from bad valve stem seals/guides/valve stems. Puff of smoke on start-up is overwhelmingly caused by valve issues.

Try running 20W/50 if you aren't already.....if you see oil appearing at the end of your "road draft" tube, check the oil baffles on the underside of the valve cover.
 

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If you could have someone follow you as your drive you could narrow down whether it's valve seals or not. At cruising speeds, going downhill, take your foot out of the gas for a while. If you get a puff of smoke when you get back into it then it's valve seals. If not, it may be the rings.

As Midlife indicated, you need to remove the valve from the draft tube for it to work.
 

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If it is the valve seals, they arn't that hard to replace. They can be replaced without tearing the engine apart. Just get the screw in adapter for spark plug hole for air compressor. Use external valve spring compressor. Not that big of a deal.
 
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