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Old 03-05-2007, 09:14 PM   #1
79blazer
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Two PVC?

I have an open element air filter. one valve cover has a PVC valve the other a push in breather.

What if I had a PVC valve in each valve cover? then run 3/8 vacuum hose to a T, then to the carb? Would that be good/bad/wouldn't hurt? Thank you
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Old 03-06-2007, 02:23 AM   #2
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Re: Two PVC?

Quote:
Originally Posted by 79blazer View Post
I have an open element air filter. one valve cover has a PVC valve the other a push in breather.

What if I had a PVC valve in each valve cover? then run 3/8 vacuum hose to a T, then to the carb? Would that be good/bad/wouldn't hurt? Thank you
In order for PCV to work correctly you have to have somewhere for air (preferably filtered) to enter the crankcase and then drawn into the carb carrying with it fumes to be burned in the combustion chambers. Creating high vacuum in the CC could cause seal failure at the crankshaft sucking undesirables into the engine there.
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Old 03-06-2007, 02:47 AM   #3
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Re: Two PVC?

That makes sense. I would think the seal would be tough, but the idea is to keep the engine as durable as possible.
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Old 03-17-2007, 08:50 AM   #4
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Re: Two PVC?

Also, a PCV is a metered air leak, installing two of them may create high idle problems. I would recommend leaving it alone. Just my opinion.
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Old 03-24-2007, 11:41 PM   #5
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Re: Two PVC?

Here's an article that explains fully the actual designed purpose and function of the system.

PCV theory
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