Charcoal Canister and vent line!

Dave81 · Post by **Dave81** » Mon May 11, 15 1:48 pm

Spent Sat taking the front end apart on the Dart.

Upon removing the Charcoal canister I found it was kinda empty (most fell out in my hand), if it had more than 3 tablespoons worth I'd be surprised!

I planned on just hooking everything back up to it when I'd repositioned it!

But......the internals look knackered (loose baffles etc), it was only connected to the fuel tank (no carb/vaccum run lines), and on trying to blow down the steel feed pipe, it felt blocked...........So this may explain why the car always has a healthy fuel aroma!

How have you guys run your vent line?

Thought is to run it locally to the rear of the car, mounting it to the floor pan, and to utilise a check valve for negative pressure within the tank?

I could run it to the front, but it seems silly (and expensive) to run a vent line towards a huge heat source.........

Open to suggestions?

drewcrane · Post by **drewcrane** » Mon May 11, 15 2:32 pm

Yea they sure do stink of fuel, yea I removed mine and I got a call from the apt. manager at the time, the car stunk up someones apartment ,cause the car was parked directly under their unit.

I would run the new one so you can get to it ,but not see it, there is a place in front of the fuel tank ,should be a nice flat part to mount it to,the same place to mount an electric fuel pump too.

MilesnMiles · Post by **MilesnMiles** » Mon May 11, 15 4:39 pm

What does it do? I've always ignored them

drewcrane · Post by **drewcrane** » Mon May 11, 15 6:52 pm

MilesnMiles wrote:What does it do? I've always ignored them

They when hooked up properly ,they will absorb the vapors of the fuel from the tank. they do work, when new, if they are old most people just threw them out,including me, now that I have 2 carbed cars parked in the garage under the house, I wish I had them now.

MilesnMiles · Post by **MilesnMiles** » Mon May 11, 15 8:25 pm

Aha go tach Drew, thought they were some sort of emissions thing and yes, my garage does smell of fuel now I think about it!

Dave81 · Post by **Dave81** » Mon May 11, 15 9:15 pm

Cheers Drew!

Do you run any type of filter on the hose end?
I have heard that it's possible for debris to get sucked into the tank and work its way up into the carb.........believe some racers have even found tyre rubber in the float bowl.....

Miles,
If hooked up properly it takes the vapours from the fuel tank. There is also usually a line that runs from the canister to the carb. Vapour is the dumped from the canister into the carb for combustion. Most of it was to do with the Cali emission laws I believe, hence on some cars (non emission States) they were missing.

Not sure if the oil crisis in the early 70s made it appear on the entire Mopar range though to assist economy!

Has about three hose connections on the top........looking at mine, it's just dead weight as its only connected to the tank and even then I think the line in between is dead/blocked.

More room in the bay for shiney stuff then! Also worth the saving in running the second Teflon hose!

MilesnMiles · Post by **MilesnMiles** » Mon May 11, 15 9:47 pm

Ok Dave, cheers for that. I do have one but my car is full redneck state, South Carolina. Can't think emissions were high profile there in the 1970s!

drewcrane · Post by **drewcrane** » Tue May 12, 15 4:56 am

Cheers Drew! thumbright

"Do you run any type of filter on the hose end?"

no,usually removed the whole rubber tube. and block off at the carb.

I have heard that it's possible for debris to get sucked into the tank and work its way up into the carb.........believe some racers have even found tyre rubber in the float bowl.....

Charger · Post by **Charger** » Tue May 12, 15 8:28 am

MilesnMiles wrote:Can't think emissions were high profile there in the 1970s!

yup, sticker on the inner fender near the battery

probably aimed at economy due to the oil crisis, rather than saving the planet

MilesnMiles · Post by **MilesnMiles** » Tue May 12, 15 12:58 pm

wow, don't have one of those, but I do have 14.3 at idle

mustangbooks · Post by **mustangbooks** » Fri Jun 05, 15 10:18 pm

Dragging up this thread again cos I've got my canister out of the car at the moment...

Is it possible to open these, or are they sealed units? I just had one hose connected on mine, from the tank... is there any advantage in hooking up the outlet to the carb? And what happens with the other outlet ('PURGE')?

Dave81 · Post by **Dave81** » Sat Jun 06, 15 8:31 pm

mustangbooks wrote:Dragging up this thread again cos I've got my canister out of the car at the moment...

Is it possible to open these, or are they sealed units? I just had one hose connected on mine, from the tank... is there any advantage in hooking up the outlet to the carb? And what happens with the other outlet ('PURGE')?

Did lots of research on it Andy and most say it does no harm leaving it in situe. But loads remove it as it serves no real purpose post oil crisis.

But.......yours is hooked up just like mine. Strike 1.
So no real benefit to anything.

Hooking upto the carb was for fuel economy/emissions. The fuel vapour runs into the canister from the tank, from here it should run into the carb rather than to atmosphere supposedly increasing MPG.

The charcoal on mine fell through the base (loose insulated wool/fibreglass), all over the inner wing, strike 2
Purge I believe is the purge valve in the event of excessive pressure.......? think this should also be hooked up into the carb?

I'll be running a new vent line local to the tank complete with one way check valve. This though is for negative pressure within the tank when it's drinking fuel.

I will keep this at the rear.........never liked the idea of having fuel vapour running into the heat source/engine area as per the charcoal canister design.

I'll be interested to see the outcome!

On a separate issue. I tried blowing down the vent line back into the tank.......no chance.....it's blocked......strike 3. Never worked anyway!

Try the line first..........is it venting?

mustangbooks · Post by **mustangbooks** » Sun Jun 07, 15 12:43 am

I actually found a bit of info in my owners manual and a Chilton tune-up manual. There should be a purge valve fitted onto the purge outlet, which connects to the carb / inlet manifold and the distributor somehow.. gonna leave that one alone!

I did also happily find that RockAuto sell the filters for the 'vapor canister' for less than a quid, so I've ordered a couple along with some other items, if nothing else to stop the charcoal pieces escaping from the bottom of the canister!:

http://www.rockauto.com/catalog/raframe ... ttype=5000

Not sure if the line is venting, but I did notice a bit of a fuel smell this afternoon (more than usual), so I've put a rubber cap on the end of the pipe until next time I start the engine at least. I think I read about some models having a valve somewhere along the line from the tank, so that may be why you can't blow back into it? I might be talking nonsense there though!