I was doing a few things to the car this afteroon and noticed this "fuel canister" under the hood:

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The side that is supposed to go to the carb is blocked off with a rubber nipple. Is this supposed to be connected to a port on the carb? Which port? I have an edelbrock 1405 on the car now, and am not sure where to put it. I would think it would "T" into the line from the PCV valve into the air cleaner, but I'm not sure.

Sometimes when I go WOT, or if I let off the gas and coast to a stop, I smell gas. not really strong usually, but it's there. Could this be a possible cause?

 

That's the charcoal canister. The line that's on there is the vapor line coming from the fuel/vapor separator behind the rear seat which has three lines connected to vent ports on the tank. Vapors from the fuel are stored in charcoal pellets when sitting than pulled into the engine when running. The other port should go to a ported vacuum port on the carb.

The charcoal system is still used in new cars. If that system isn't working, then the fuel tank should use a vented cap.
There's a fiber gasket in the bottom of the canister that should be replaced. It can be quite tough to get an old canister out without destroying it, though.

 

This is the important part. Don't simply connect the port to manifold vacuum. If you did, it would be a large vacuum leak at idle. The correct carb will have a timed vacuum port that is only active at part throtttle and above to purge the charcoal cannister.

 

Thanks, Joe. I think it is supposed to be a pretty restricted port, also. You don't need a lot of flow through there to pull out the vapors. There won't be a whole lot, so you really don't want a lot of flow.

It's not uncommon for the canisters to fail. The inside is really just a cloth bag with carbon granules. The bag degrades, and sometimes the granules get sucked into the carb. Not good. Taking the thing out of its mount and shaking it upside down tells you if it's in good shape.
New functional replacements are also available via RockAuto and others. Slightly different port configuration, but same function and shape.

 

The timing is already connected to the ported vacuum on my ebrock carb. Should I get a "T" fitting to connect both of them?

Or will the T just create more problems? I'm wondering if this being plugged is the reason I smell gas occasionally.

 

It needs to be a different port, as the canister will actually flow air. So if you T it, then your advance will never work right.
Hopefully the carb has a separate 'emissions' port or something. Might need to call edelbrock and ask where you're supposed to connect the 'charcoal canister purge line'.

 

Mines plugged the same way, I never smell gas. If all you other lines are good Maybe check the small rubber line under the passenger floor where it goes thru the frame that could easily be overlooked

You could swap the VA to manifold vac and run the canister on the ported vac, I just switched my HEI to manifold vac from ported along w some other changes I'm pretty happy w it

 

So if your carb does not have a ported vacuum then plug the charcoal canister?

 

for the longest time I just had the one line on the canister, I only recently plugged it for appearance sake

 

I put a filter between my canister and carb. When these get old, charcoal can get out and into the carbs. You dont want that.

 

If you can't set it up properly, then you might as well yank it and sell it. If it's in good shape then it's worth some money as they're not repoped. The service replacements have a completely different appearance.
Plug the three vent lines on the tank and get a vented cap.