What are the Correct Charcoal Cannister Connections?

[opelgtman1973]

I have the OGTS diagram, which you can see here:

http://www.opelgt.com/photos/showpho...sort/1/cat/533

It shows the cannister with the connections pretty much horizontal, with the tank connection on the left, the carb vent ported vacuum in the middle, and the float bowl vent on the right.

Mine is mounted with the connections oriented vertically. The top connection is to the tank, the middle is carb vent ported vacuum, and the bottom is the float bowl vent. The order of the connections matches the OGTS diagram, just rotated 90 degrees CW. However, I found this pic of someone else's cannister, and though it's a little hard to see, it appears that the tank connection is not on the top. http://www.opelgt.com/forums/showthr...ight=cannister

Can anyone confirm these for me?

[greensmurf20]

may be off subject a little bit but here goes the question...
since there is a vent line from the canister to the fuel tank venting system, and there is a vent from the gas tank to the outside air underneath the car......wouldn't that be a indirect vacuum leak?

[namba209]

Jared, if the tank vent lines are hooked up correctly, there is no vent from the tank to the outside of the car. Perhaps you are referring to the vent lines that go to the inside of the car to allow flow through ventilation. JMTCW.

Ron

[greensmurf20]

sorry guys, stupidity kicked in while i was about to fall asleep in computer class today. forgot the hose coming out of the bottom of the car hooks to the black plastic line going to the charcoal canister........sorry...was thinkin back to the days of the red GT where i didnt have a charcoal canister, and it just vented into the outside air.

[namba209]

Not a problem Jared, I've been known to "open foot - insert mouth" more than once on this site and others.

Ron

[kwilford]

There are three connections on the charcoal cannister:

1) from the tank
2) from the carb bowl vent
3) to the carb throat (at least on the stock Solex)

The first two connections are "sources" of raw gas fumes. The fumes that get created in the gas tank and carb bowl leave under their own pressure, and get adsorbed ("stored") in the charcoal inside the cannister. When the engine is running, a small vacuum is created at the carb throat, which causes the fumes to desorb (come out) of the charcoal and get burned in the engine.

Most Webers don't have a bowl vent, so that connection to the cannister must be blocked off. And there usually isn't a throat vent connection either, so my preference is to connect it to the air cleaner body, downstream of the air cleaner where there will be a slight vacuum created, so the fumes vented off the cannister still get burned.

Some folks try connecting the cannister vent to one of the carb or manifold vacuum ports. Now THAT will act like a vacuum leak, and will also pull the gas tank into a vacuum, which is turn will cause a vapour lock. NOT a good idea!

JM2CW

[kwilford]

Here's a photo from a FSM, that shows a different hose connection than OGTS

[kwilford]

Here's the OGTS illustration

[mjewell]

my '72 gt has a weber, so there are two hoses that go nowhere. what if i were to just take the cannister out of the car altogether? would i just leave the one that's on the cannister now hanging in the nose? should i leave it in?

just curious.

mike

[opelgtman1973]

I thought about just removing the whole shebang, but I read Keith's writeups about it. Personally, I'm going to be hooking mine back up to avoid gas fumes and other problems. Here are two links to some great info. Thanks Keith

http://opelgt.com/forums/showthread.php?s=&threadid=856

http://www.opelgt.com/forums/showthr...&threadid=1317

[pvcar]

well i say just get a can off of an 80's car from a pic u-r part yard that has two hookups on it run a line ffrom those gas tank vent hoses to the front and hook it up to the normally bigger connector on ur new can and hook the other up to ur air cleaner some how. like i always think id rather now that those gas fumes are going some where safe and not that one day i walk out to start the old opel up and bang big explosion yah no what im sayin.

[opelgtman1973]

Ask Keith described in those threads I posted, you can just plug one of the connections on the original canister. You shouldn't need to get another one, unless yours is plugged I suppose.

Keith also has a picture of how to hook the hose up to the Weber air cleaner using some brass fittings. Just scroll down the page a bit and you'll see it. HTH

[kwilford]

Now this is my kind of thread. I get all the glory, and don't do any of the work!

[opelgtman1973]

Originally posted by kwilford Now this is my kind of thread. I get all the glory, and don't do any of the work!

Hey, you already did the work

[pvcar]

well the reason i got a newer one was because it wus smaller and also most of the ones i had seen on gts have been pretty used and are totaly soaked in gas fumes. yah im running the stock air cleaner but what i did wus when i swithced over to the weber 32/36 and had to cut off the little lip there so it all fits under the hood i also cut off that tube that came out and brazed it over and made anthor one.

[opelgtman1973]

Originally posted by pvcar well the reason i got a newer one was because it wus smaller and also most of the ones i had seen on gts have been pretty used and are totaly soaked in gas fumes.

pvcar, that's a good point. Always nice to have newer stuff. Plus, there's so little room on our GTs, it's nice to squeeze out a little extra. For now I'll just stick with my old canister. Higher priorities, you know.

[pvcar]

hey opelgtman1973 i noticed ur in so cal to well if u see a red opel with a balck stripe down the center thatll be me, hopefully i can get the windows in by next week.

[opelgtman1973]

Hey pvcar, yeah I'm currently in L.A. If you see a black primer GT driving around, it'll be a freakin' miracle Been trying to get it on the road for a couple months now. Every time I fix one thing, there's something else that goes wrong after a couple days of driving. But I'm persistent

I'll keep my eyes open for your GT. I've only seen 4 others here in L.A. / O.C. -- a nice red one in Studio City, a yellow one in Mid-Wilshire, and a gold one somewhere in Anaheim, and another red one in Fullerton.