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What is this?

Hey all. I was looking at my gt's engine today and noticed something i hadn't seen before. It is some cylinder part with 2 unhooked hoses. Can you guys tell me what this is and hows my car is running fine without it? What should i do? Thanks
 

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The charcoal cannister gathers and stores gasoline fumes from the gas tank, and in the case of the stock Solex, the float bowl. Then it expels those fumes to the carburetor throat to be burned. With a Weber, there isn't a standard connection to allow the cannister to vent into the carb, so many folks just leave it disconnected. But then they complain that they smell gas fumes, since it just vents into the engine compartment. Or worse, they plug the vent line from the gas tank, which causes the tank to pressurize, and then the vent hoses blow off the tank filler or burst, and then they get smells from the back of the car. It would appear that some P.O. of your GT at least tried to leave the cannister vent near the carb throat, but it won't ensure that fumes will enter the carb. It really needs to be connected inside the filter housing.

For the compleat story, go to

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

and also search under "cannister". Most folks connect the cannister vent and the valve cover breather hose together, so the PCV system and cannister get connected together. So also search under "PCV" for hints on how to do that.

HTH
 

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...run the hose too one if the vacume ports on your intake to suck the fumes out of the co2 canister...

It's not a CO2 cannister, but a gasoline fume canister. And I don't think that would be good idea. While it is true that the Opel PCV system uses a vacuum port (albeit a METERED port) to draw out crankcase fumes from the valve cover at an idle, it happens at a low rate (hence the metering orifice) and the breather hose (the big one on the valve cover) prevents the crankcase from being drawn into an actual vacuum.

If you were to hook the cannister up to a true intake or carb vacuum port, you would cause the fuel tank to be pulled down into a vacuum, which would certainly exacerbate fuel vapour lock. Not to mention make it difficult to remove the gas cap while the engine was running :)
 

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4ZUA787
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charcol can

i just got a can off an 80's mazda and mounted it up by the stock cannister would have been looks really good it only had one in and one out instead of three house connections. i also have a weber on my opel so it doesnt connect there. what it does right now is i have a 1/4 inch copper tube from the tank went in back all the way up to the can in front and then i little house that just sorta dangels out the bottom of the cut out they made to put the battery in for the a/c equiped gt. u can see a pic here http://www.opelgt.com/photos/showphoto.php?photo=981&password=&sort=7&thecat=500
 

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If you want to have the vapours burned in the carb instead of venting to the air, just run a length of hose from the open fitting on the cannister to the air filter. Since you have a Weber instead of the Solex, there isn't a float bowl vent, and you only need the two hoses. What I did (and I have seen done before) is to install an elbow or a tee under the air filter can, INSIDE the filter (so it sees some vacuum when the engine is running). I used a tee, since I also connected the breather hose from the valve cover to the same fitting. The cannister connection is on the right, with the breather connection on the left.
 

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And here is what it looks like from inside the filter housing. I had to install the tee, but I have seen this style of filter come with the fitting from the factory. Oh, and no comments about the Weber that this is on. This is my old 32 DFM, which is the "Pinto" style carb, with the inverted throttle butterflies. I have a 32/36 DGAV, but it is currently in the soak tank, pending a rebuild
 

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evap can

well i have a 32/26 on my gt but with the adapter so i can use the origanlal air filter assembly. but with the adapter plate in there it makes the fresh air vent conection in accesible for the valve cover. so i took and cut the 1 inch piece of tubing off and brazed a small piece of metal over the opening so that it is blocked off. then i just got a k&n crankcase filter that fits niece and snug in the hole on the valve cover and looks pretty cool. and works awsome.
 

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Really old thread, I know, but I had a question here. Doesn't the flow for the "PCV" system flow from the air cleaner to the valve cover? If so, with the two lines tied together, could you be pulling gasoline fumes into the crankcase? I know, probably a very minute amount, but I think the vacuum pulling that direction is more than the vacuum from the carb throat.
 

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The early evap system is very crude.
The bed of charcoal in the cannister stores the HC vapors from the fuel tank
until the purging when the motor is running.
 

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Really old thread, I know, but I had a question here. Doesn't the flow for the "PCV" system flow from the air cleaner to the valve cover? If so, with the two lines tied together, could you be pulling gasoline fumes into the crankcase? I know, probably a very minute amount, but I think the vacuum pulling that direction is more than the vacuum from the carb throat.
Nope. With ANY amount of crankcase blow-by, the valve cover area is always at a greater pressure than the carb intake, so the carb sucks blow-by gas and charcoal off-gas (containing absorbed gasoline from the gas tank and Solex float bowl) into the carb throat where it gets mixed with the air/fuel mixture and burned in combustion. In addition, the small line from the intake manifold pulls a vacuum when the throttle plate is closed (at idle) which pulls a slight vacuum and actually "sucks" a bit on the valve cover, depending on how much blow-by gas is being generated. If more air is sucked by the PVC orifice than blow-by gas is generated, the big hose feeds filtered air (which is why it is connected downstream of the filter) into the valve cover which is then mixed with blow-by gas and sucked into the PCV orifice and "consumed" in the combustion process. If more blow-by gas is generated than the orifice pulls, the excess blow-by gas goes OUT the big hose into the carb throat.

In other words, the PCV system on an Opel both sucks AND blows :)

HTH
 
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GM dealer would be the place to check for the parts you would need. The canister was used on a number of GM cars from the same year models. The kit I saw had the refill charcoal pellets and the lower filter and screen.
HTH

John
 

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