Question about Charcoal cannister

[scrapman]

I am looking for some information on the charcoal cannister. Mine is on a 73 Manta.
1. What does it do? Any general information would be appreciated.
2. Mine is leaking out charcoal. The upper end is open.
3. Is there a certain kind or amount that goes in it?

Not seen a problem with it in the past. Is there a specific site or information place I can get to know this piece a little better? Thanks

Scrapman

[baronbors]

Originally Posted by scrapman I am looking for some information on the charcoal cannister. Mine is on a 73 Manta. 1. What does it do? Any general information would be appreciated. 2. Mine is leaking out charcoal. The upper end is open. 3. Is there a certain kind or amount that goes in it? Not seen a problem with it in the past. Is there a specific site or information place I can get to know this piece a little better? Thanks Scrapman

I may be wrong but on the GT it is set up to absorb the fuel vapors from the gas tank vent lines.
I think you would be best to just get a used replacement and not try to fix your old one

[GTJIM]

The charcoal canister is and important part of the emission control system. It is there to minimise the venting to atmosphere of fuel vapour from both the fuel tank and the carby's fuel bowl. It does this by absorbing the fuel vapour from the "air" that moves in and/or out of these two places while the car is running or stopped. THe carbon in the canister is known as "activated" charcoal as it is specially made to have a very large surface area which has the ability to store fuel molecules. As the vapour moves in and out of the fuel system the actual hydrocarbon molecules are absorbed by the carbon to be removed through the third line that "sucks" it back into the motor to be burnt during high vacuum conditions.
It is probably not possible to refill the canister effectively and you can really only replace the whole thing. Many if not all modern cars have charcoal canisters made of plastic instead of steel like the GT has - so they don't rust out and let the charcoal escape. One of the newer plastic canisters can be used as a replacement.
There - HTH!

[kwilford]

Moved thread to the "Fuel Tank, Lines, Filters and Venting" Forum, where a quick search will turn up several threads on Charcoal Cannisters.

HTH

[Dan-MI]

I'm looking for one too, for a GT. Mine has none and the PO's mechanic did a weird plumbing job of hooking the carb up to the brake booster instead of the charcoal cannister. I read the some of the other postings and they say any 70's era car would have one. Well the local parts stores all had pretty dumb looks when I ask about it. Anyone know a particular vehicle that you could scavenge from or where you could get an Opel one? OGTS do not list them in their catalog.

[namba209]

What I did for a charcoal cannister on Willit? was to go through the books at my local Kragens, these folks have been very helpful on both the GT and the monza, We ran the different cannister part numbers for GM looking for the cheapest that would work and came up with one for around $40. Some were over a $100, and came up with a Rochester Control Products 3-port unit. It has 3 sets of numbers on it so I'll give them all. "PA66", "20341", and "17075840-FL". The ports are labeled "VAC" "PCV", and "FUEL TANK" It is a bit smaller diameter than the original cannister and all plastic with a filter element in the bottom. HTH.

[markandson]

you can find it at rockauto.com if you punch in 17075840 into their search engine for part number.

[scrapman]

Thanks for the info. Maybe you can clarify another question. You mention to replace it with a plastic one. My 73 manta has a plastic one already mounted to the left front wheel fender with the back end tilted upward and hidden from view. The back end appears to not have a cover on it. Am I dense or shouldn't this be sealed??? First time I've noticed it since I got the car.
To add to it, my 71 GT has the metal vent cannister. Can both can be replaced with one of the part numbers Mark or Jeff indicate or are they different because of the different vehicles?

Thanks - Rick

[GTJIM]

Here is a picture of my Isuzu charcoal canister. The bottom has a hole with a short plastic tube that is open to the air - as the air has to get in and out as it is just the fuel vapour that the activated carbon removes as the fuel tank and carby fuel bowl "breathes". The outer end does need to be open to allow this to happen - I guess some canisters are completely open at the lower end. Indeed there is nothing to stop the canister being up the other way as long as the carbon does not fall out ....

[namba209]

The one I got for Willit? is actually open on the bottom, kinda sorta, there is a vacuum cleaner paper type inlet filter there. The can must really be full of charcoal because when I shake it it doesn't rattle around. I have the original cannister from my GT and it's metal and pretty much rusted out in places. The reason for replacing it, and it is open in the bottom also. As long as the ports on the can will work, there's no reason why one can't be used on both GTs and Mantas.

[GTJIM]

Remembered a canister bolted to the front cross member of a GT front clip flown in from Texas (Thanks! Brett B.)
Dug it out and found it still mounted to the remains of the cross member.
The surprise came when I unbolted it and saw that it was an AC brand - Made in England!
The end protected by the pressed sheet metal shield mounted on the cross member has the remains of a foam filter in it - other wise it is an open, perforated plate in there behind the foam filter.
Here are some pics:

[spdkilz02]

i dont even have mine hooked up for my gt, the thing is this there.

[scrapman]

Thanks Guys. I appreciate the feedback. I know a lot more than I did yesterday! One last question, since the end is open, is there any reason why dumping some activated charcoal from the local pet store in the aquarium supply department and securing the end with a foam filter or even a fine mesh screen would not work and cut down the gas odor from the fuel venting?
Rick

[GTJIM]

Guess if it comes out it can be put back in!
But good used ones are so cheap at "Pick-a-Part" that is it worth it?

[spdkilz02]

like i said i dont even have mine hooked up to the car. and everything runs fine and i dont even have an gas smell at all.

[Lindsay]

Thanks for the Info regarding AC Delco 17075840 FUEL VAPOR C. If the diameter is smaller than OEM, could canister be mounted sideways like OEM GT in original bracket?

Noticed that www.partsamerica.com has reduced their P/N selection and increased prices! Find myself looking more at www.rockauto.com.

Thought of using activated charcoal in my old GT vapor canister, but haven't visited pet supply store yet. Have metal canister that I cleaned and repainted. Don't have the OEM restriction hose located at one of the ports, but could rig-up something.

Autozone sells filter that is used at the end of the canister:
AutoZone CF413 Deutsch 4" diameter.

Alway the dilemma ...
Do I keep it STOCK or improve the function?

[GTJIM]

Originally Posted by Lindsay If the diameter is smaller than OEM, could canister be mounted sideways like OEM GT in original bracket? Have metal canister that I cleaned and repainted. Don't have the OEM restriction hose located at one of the ports, but could rig-up something. Alway the dilemma ... Do I keep it STOCK or improve the function?

If you find one that is slightly smaller in diameter you may be able to empty out the insides of your original steel canister and slide a new plastic one inside it. Hook up the hoses through the end and have the best of both worlds - original appearance with modern functionality .......
That is where many of our GTs are headed anyway!

HTH

[namba209]

Oops, sorry folks, I made another mistook. The cannister I got is larger than the OEM by about 1/2" diameter. I made the error because I couldn't find the original bracket and used the wiper water tank bracket for the cannister. Now I gotta find the original bracket and see if it wiil work with the new cannister. Hopefully it will and I can mount it somewhere else up front, if I can find the room.