More has been revealed thru google searches... i ask a friend what this was for mounted behind the rear seat, he said rear window defogger... Guess not!
I didnt realize the 1972 used a charcoal canister. This drawing might be from an earlier year, by 72 canister might have had a vacuum signal from the carb and dump into the PCV
Rear window defogger! Nice one It's a high point closed top stove pipe where the central and two side tank vent lines route to. Another line then goes to the charcoal canister in the engine bay. Vacuum in the air filter horn then sucks vapor from the canister into the air flow. I'll post a copy of the newer model diagram later. Bob
That system with the stove pipe began in 71. There are date coded stamped on them. It was an elaborate system to control gas venting into the air for emissions control.
It was an elaborate way to keep gas from venting into the atmosphere. I call it the AOC option. I don’t think she would understand it though. The vent stack have date codes stamped on them.
If you need a charcoal canister with the mounting bracket,I have one of those.As the guy's here would say- What's there that you don't have? Bruno.
Thanks, you've just solved a mystery. I was wondering, when I gutted the interior of my 72, what this vent was for and why it was not connected to anything. Previous owner dropped a 70 455 in it (no cannister) so everything makes sense. I guess it'll stay there hidden behind the rear seat during rebuild, as I'm planning on keeping the same engine. I assume my plan is of no concern, right?
If you deleted the charcoal canister and the lines running to the front of the car. Could you theoretically run a hose from the stovepipe thing out, say one of the rear wheel wells? Or a different route? Just thinking as I deleted all the emissions stuff but obviously still want to use the vents on the tank.
For my EFI conversion I simply ran the vent hoses from the fuel pump and tank to a Y connector and then up to one of the original hoses in the stove pipe. I've removed all of the vent hard line and the charcoal canister. The vent needs to terminate high enough to not allow for any fuel slosh to cause a spill through the vent line. As long as the stove pipe is not rusted it should be a closed void and only allow air to be drawn in from under the car as fuel is consumed. The new fuel tank I used actually came with a roll over valve that will seal the vent in the case of a rollover. I didn't use it on the grounds that if I ever managed to roll the Electra spilled fuel is likely the least of my worries Bob
Very helpful. I believe it was done as stfsocal describes but I'll have to confirm. Anyone else have experience with this 72 gone 70 fuel venting?
When i was upside down and crawling out the drivers window, thru the broken glass and gasoline, i kind of wish there wasn't the gas. it's just a mess and gets all over your clothes. I'm just being a smart ass.. I pray you never wind up on the lid. BTW i was going about 20mph. Crazy Cheers!
What the hell happened?!?!? Glad your ok man but geez. This the car this thread was talking about?? When did the accident happen??
You need to set it up based on your gas tank. You don’t have a 70 gas tank so you can’t set it up that way. The engine doesn’t care what year the car is. I think the easiest thing is set it up properly or maybe block the vents at the tank. Then again that might cause an over-pressurized tank?
The tank needs to vent in order to draw air in as fuel is consumed and to handle expansion/contraction due to temperature changes. My new tank only has a center vent and an additional vent on the pump so I just ran those together and then up to one of the stove pipe connections. Not had any problems running like that. If your tank has all of the vents then I'd connect them as shown in the diagram if you have all the pipes and connections. You could cap the two side vents and just use the center ones and be fine. Bob
