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pcv system and valve cover question


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I was looking over my pcv system today: I had the car running with no hoses on the nipples of the valve cover and there was air coming out of the nipples on both sides :slobber:. Why would my crankcase be pressurized, this from blowby or is it meant to be like this?

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the pcv is designed to cause a draft acoss the engine by introdicing air in one side and fumes out the other.

 

the valve controls the flow of the gases in one diretion, otherwise the same gas would pulse in and out but not circulate(as you describe)

 

the hoses will be on one side will let in fresh air from the air filter, the ther side will connect to the pcv valve itself

pcv.JPG

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i have the carbed version so I 'should' only have one t piece on the pcv valve side hose. Curently I have it running straight out of the valve cover to the valve, no t piece. What is the purpose of the t piece, no. 14 on ur diagram, that has the approx 1/4" id tube running to the air cleaner? I remember in the stock air cleaner there is a small filter when the pcv get its 'fresh air' from, do you need this?

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looks to me to kelp mix up the gases with air, but then again, it reminds me of a balance pipe on a dual exhaust, the gases and air would probably reverberate in this passage, pulsing type forces, and hence the check valve on the pcv to keep the gases moving in one direction.

 

it may be there for whatever gases would otherwise pass thru to the atmospehere(emissions control)

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i have the carbed version so I 'should' only have one t piece on the pcv valve side hose. Curently I have it running straight out of the valve cover to the valve, no t piece. What is the purpose of the t piece, no. 14 on ur diagram, that has the approx 1/4" id tube running to the air cleaner? I remember in the stock air cleaner there is a small filter when the pcv get its 'fresh air' from, do you need this?

 

You're Carbed version also incorporates the Air Suction Valve/anti afterburn system into the equation. The 1/4 inch tube that goes into the aircleaner is part of the ASV system. It allows for fresh air to be introduced to the exhaust pipe when the pressure inside the exhaust goes negative. This helps prevent backfiring. It can all be removed though if you like. Plug the holes in the head where the ASV pipes attach. remove the ASV hoses and just plumb the 2 valve cover tubes to the Pcv.

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