So, what the heck is this?

[RandyMolson]

I am told it was found on a 67 or 68 1600. It is grey plastic, marked Hella, and the only openings are the two hose nipples shown.

[esty]

that's a vapor canister that goes in the trunk...right hand side, just under the rear package shelf...i might be wrong but i believe all o2's had those....my 69, 72, 74, & 76 has one

[RandyMolson]

Ha ha. Some guy parting out a 1600 had sent me that when I asked for a the windshield washer reservoir.

I'm kind of curious. Seems like a little plastic bottle mounted in the trunk is not going to be much cooler than the fuel tank, and is not going to condense gas fumes. Has anybody heard that this thing actually works?

[Marty]

It's not for condensing the fumes it's just a reservoir for the fumes until the engine is started and provides vacuum to the charcoal canister under the hood and then its vented into the air cleaner and sucked into the carb.

[eastsidebimmer]

We prefer to vent everything to the ground and sky, just as it should be!

Ben

[TobyB]

I thought it showed up in '71. Neither the 69 nor the 70 has the clippy- thing under the parcel tray to hold it in place...

t

[BLUNT]

my 70 california shell has it

[Jayson]

My '70 cal has it as well. Do we need it?

[Arshloch]

68', doesnt have it. All the fvapours are vented thru the whole in the trunk.

I think it's useless

[Mike Self]

a factory parts book and it'll tell you the VIN at which they were first installed...my early second series '69 is devoid of any vapor recovery stuff, and I had always thought they began fitting that stuff with the two bbl Solexes in late 72, but apparently not.

mike

[RandyMolson]

It's not for condensing the fumes it's just a reservoir for the fumes until the engine is started and provides vacuum to the charcoal canister under the hood and then its vented into the air cleaner and sucked into the carb.

We are dealing with a vent system that dead ends at the fuel tank. The only way I can see this working is if the running engine draws enough of a vacuum, that when the engine is shut off, fresh air from the air cleaner fills up the vent pipe and reservoir. That seems like a lot of air volume displaced by the compressibility of air.

[Marty]

Yes that would be a large reservoir for storing air but we are storing a much more active substance gas vapor, air is free to enter or leave the system through the charcoal filter as the tank breathes the charcoal with holds the gas vapor with in the system. This vapor is either drawn back into the tank as fuel is consumed or is drawn into the air cleaner and burned.

[RandyMolson]

Yes that would be a large reservoir for storing air but we are storing a much more active substance gas vapor, air is free to enter or leave the system through the charcoal filter as the tank breathes the charcoal with holds the gas vapor with in the system. This vapor is either drawn back into the tank as fuel is consumed or is drawn into the air cleaner and burned.

I think I see your theory. Fuel consumption draws clean air into the vent system so it is all full of clean air upon engine shut-down. Thus, the reservoir adds the volume of clean air that must be displaced before the fumes make it to the carbon canister when the car is sitting. In practice though, I imagine that a jostling fuel tank sitting on top of a hot exhaust system is going emit more fuel vapor than the gas consumption. Therefore, the vent system is going to be full of gas vapor upon engine shutdown. Unless the designers were trying to use thermodynamics of compressed air to purge the vent line with pure air for when the engine is not drawing a vacuum (which I doubt), the reservoir serves no purpose. It doesn’t matter how big or small the reservoir is, if the vent system is full of fuel vapors, the volume of fumes in (from fuel tank) = volume of fumes out (into the carbon).