Deleting Charcoal Canister

[MrBonus]

I recently upgraded to a larger SC fuel tank and the charcoal canister no longer mounts flush and is frankly in the way.

Is there anything special I need to do to remove it? Am I going to get a stench of fuel in my garage? Is there a more compact 'upgrade' to be done here?

Sorry if this is a stupid question.

[spedrcr]

I removed mine from the RR fender well (3.2 Carerra) and now the fuel system vents to atmosphere in the LF fender well. I have never experienced any fuel smells at any time whether driving, parked, enclosed garage, ect.

[EC900]

Do you intend to keep the expansion tank ?

This is the first place where most of the raw fumes collect before entering the charcoal canister and via check valve, vacuum drawn to combustion chamber to be burned off. The charcoal merely absorbs and stores those vapors until the point they are released back to the engine.
Part of the emission system but doesn’t affect performance and miniscule vac leak will be present unless plugged.

When I was doing work, I removed the expansion tank to get to the washer fluid tank, had the exp tank vent hose hanging outside under the ft.left fender for a months and the fumes were very noticeable, almost as what would be expected with a missing gas tank cap.

So remove the charcoal can, venting has to be outside of the trunk because fumes may return from the engine, it’s a cycle that’s repeated during engine running. I cant say the recirculation process is the same for early engines as it is for MidYears emissions equipment.

You might have to try it and assess the results.

[MrBonus]

Originally Posted by EC900

Do you intend to keep the expansion tank ?

This is the first place where most of the raw fumes collect before entering the charcoal canister and via check valve, vacuum drawn to combustion chamber to be burned off. The charcoal merely absorbs and stores those vapors until the point they are released back to the engine.
Part of the emission system but doesn’t affect performance and miniscule vac leak will be present unless plugged.

When I was doing work, I removed the expansion tank to get to the washer fluid tank, had the exp tank vent hose hanging outside under the ft.left fender for a months and the fumes were very noticeable, almost as what would be expected with a missing gas tank cap.

So remove the charcoal can, venting has to be outside of the trunk because fumes may return from the engine, it’s a cycle that’s repeated during engine running. I cant say the recirculation process is the same for early engines as it is for MidYears emissions equipment.

You might have to try it and assess the results.

Thank you for these details. I have no clue what I'm doing here. lol

[MrBonus]

I really need to trace these lines. I doubt all of this hardware is still present.

[PeteKz]

I did this on my 1973T. Not hard.

You will need to remove or plug the 2 hoses and lines that go back to the engine bay. I removed them completely and plugged the 2 hard lines at the firewall that come through the tunnel to the lower engine bay.

Up front, remove the canister and either remove the breather lines that come from the engine. Since you plugged them at the other end, you can just leave them loose or remove them.

There are two expansion/overflow tanks. #1 is under the cowl on the driver's side in front of the instruments. In my car, it had two cracks in the plastic that caused a strong fuel smell inside the cabin when I was above about a half tank, and at other times. I removed and repaired it by sealing over those cracks with silicone sealer. It's a PITA to get at, because you have to remove the left hood hinge to get it out (and then realign the hood after you put it back together). It's at the highest point in the system so that any expanded fuel can go up there first and then drain back into the filler pipe when there is enough room. Otherwise, it overflows into the plastic tank #2 in the left front wheel well.

Fuel caught in the #2 tank will eventually evaporate and get held by the cannister and sucked into the engine air cleaner housing. This should only happen if you REALLY overfilled the gas tank and then parked out in the hot sun for hours. Because I stop fueling when the gas pump handle shuts off, and I then get back in the car and drive it a few miles to get home, or wherever I'm going, I don't think the fuel in my car has ever overflowed to the #2 tank. Therefore, I removed it too. If I ever overfill the gas tank that far, the little bit of overflow will end up on the ground. To prevent dirt from getting back up the pipes and hoses to the #1 tank, I put a cap on the pipe where it comes through the inner fender and made a small slice in the rubber cap, so that excess pressure can vent (this is necessary, otherwise you will build up pressure in the fuel system with potentially dangerous results). I then capped the other line going through the inner fender to the charcoal canister to keep out dirt.

[chrismorse]

That was me. Shortly after acquiring the old 308, (77), i noticed fuel leaking on the right side after a fill up and parking the car on a side slope.
Being somewhat irreverant about smog junk, i just ripped out all the old cracked cloth covered rubber "fuel vent hoses", plugged the open fittings and drove the car - fine around town.
However, When i drove to my first ferrari event, (200+ miles away), the car began having problems going up hills around santa rosa. Havng been a service manager, (not smart enough to be a mechanic), I hastily diagnosed - a bad fuel pump, so did an awkward pump replacement in a napa parking lot, 175 miles from home.
Car ran fine on flat ground, but struggled on hills - disappointed, untill i got to a gas station and opened the fuel tank cap, with a big hissing sound - and a very dim light just went on - maybe the tank needs a bit of air to compensate for the fuel drawn out during running.
So, let the sad, cautionary tail remind you to figure out the tank "venting", before you start cutting and plugging.

I am working on the venting on a 74 restomod, as we speak - hope to avoid a relapse.

regards
chris