PCV- worth the factory "re connect"
Thread Starter
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
PCV- worth the factory "re connect"
I've been crawling around my '82 and see that the PCV valve has been altered from factory specs by the PO.
I see that the PCV line goes right from the valve cover into the intake manifold. It completely bypasses the solenoid control for the charcoal canister which is properly plugged.
Additionally, the PO disconnected and removed the Air pump and diverter so the emissions controls have been modified. The ERG is in place.
The cars runs very well so I'm hesitant to mess with it, however I'm left wondering if there is an advantage to reconnecting the PCV system so that the charcoal canister operates?
I see that the PCV line goes right from the valve cover into the intake manifold. It completely bypasses the solenoid control for the charcoal canister which is properly plugged.
Additionally, the PO disconnected and removed the Air pump and diverter so the emissions controls have been modified. The ERG is in place.
The cars runs very well so I'm hesitant to mess with it, however I'm left wondering if there is an advantage to reconnecting the PCV system so that the charcoal canister operates?
Melting Slicks
Joined: Jun 2006
Posts: 2,071
Likes: 147
From: S Nevada
My thoughts are that the pvc system with charcoal canister does no harm. I retained it when rebuilding my car. If you have the parts, why not hook it up? Many times "back in the day" these items were chucked by over zealous hot rodders.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If you hook it back up, make certain to check the type of fuel cap it has on it. When new, the charcoal canister also performed the function of the tank VENT. When folks disconnected them, they usually installed a vented gas cap. For system to work properly, the gas cap must be non-vented.
As mentioned, the only reason to NOT hook it up would be that is doesn't work properly. But, you can hook it up to find out.
The vacuum 'switch' on top of the canister allows the canister to 'purge' vapors back into the fuel charge. That should only occur when the car is not idling. That switch was connected to 'ported' vacuum so there would be no vacuum available at idle condition, and the switch would remain OFF until the throttle was opened during normal running.
As mentioned, the only reason to NOT hook it up would be that is doesn't work properly. But, you can hook it up to find out.
The vacuum 'switch' on top of the canister allows the canister to 'purge' vapors back into the fuel charge. That should only occur when the car is not idling. That switch was connected to 'ported' vacuum so there would be no vacuum available at idle condition, and the switch would remain OFF until the throttle was opened during normal running.
Last edited by 7T1vette; Apr 12, 2016 at 09:44 AM.
Racer
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Pcv
https://willcoxcorvette.com/catalogs..._year=32&q=pcv
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Racer
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Neither your post or profile indicate the year of your car. The link below is for a 1982 PCV
https://willcoxcorvette.com/catalogs..._year=32&q=pcv
https://willcoxcorvette.com/catalogs..._year=32&q=pcv
Racer
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Race Director
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Neither your post or profile indicate the year of your car. The link below is for a 1982 PCV
https://willcoxcorvette.com/catalogs..._year=32&q=pcv
https://willcoxcorvette.com/catalogs..._year=32&q=pcv
Racer
Joined: Apr 2011
Posts: 471
Likes: 3
That's the PCV I have it has 2 ports, one to the canister and one to manifold vacuum port. I bought an older style canister that only has two ports instead of multiple ports the '80 came with. The other port goes to the fuel tank vent line on the drivers side. No more stinky garage.
Thread Starter
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
I pu the PCV back togehter as factory with the two port version.
I checked the engine with the vacuum gauge and the hg increased by 1 (16-17), super steady and the engine idle went up a bit.
I'm wondering if the additional pull from the canister increased the air flow and gave everything an additional bump?
I checked the engine with the vacuum gauge and the hg increased by 1 (16-17), super steady and the engine idle went up a bit.
I'm wondering if the additional pull from the canister increased the air flow and gave everything an additional bump?
Race Director
Joined: Mar 2016
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From: Napa Valley California
I just brought my new 73 home on Saturday. Parked it in the garage and the stink is so bad I pulled the air cleaner off and started looking for any fuel leaks. I found nothing was leaking however I remember reading this post about properly hooking up the canister. My 73 has the 454 and the line leaving the canister runs directly to a T on the PCV valve. From the T on the PCV the line is plugged into the port on the intake manifold in front of and just below the carburetor. The smog pump has been removed and there are several vacuum plugs on the carburetor. On my 73 does the canister line run directly to the carburetor? If so, what vacuum port on the carb? Does the PCV run directly to the intake port in front of and below the carburetor? Thanks Guys...