Charcoal Canister

[dc914guy]

I got my hands on a complete hose kit for the 914 on evil-bay for $50, it came with a nice diagram of the engine and where all of the hoses go, however the diagram included a ‘charcoal canister’ on it. The diagram is labeled 1975 – 1976 914 2.0

I have a ’75 2.0, do I need this part? What does it do?

Thanks for the help,
~Eric

[norustscott]

Eric,

The canister is to catch fuel vapors the would eminate from the fuel tank. It goes under the hood on top of the gas tank. You should have two 12mm hard plastic lines that run down the drivers side, behind the rocker panel from the engine bay to the left front wheel well. Cloth braided 12mm vacuum line made the final connection along with a much smaller line that connects to the small vapor catch on top of the gas tank to the charcoal canister.

Do you need it? no. What does it help? clean air .. maybe. If you do not install you will need to plug a seven holes.

1. the samll hole at the filler neck.
2/3 the holes in the wheel well(car body) that lead to the gas tank area.
4/5 the similar holes that lead into the engine bay under the relay panel.
6/7 one hole in the air intake box and one either on the fan shroud or the cylinder sheet metal next to cylinder number 2. I have seen both.

How it works,

The cooling fan supplied positive air pressure to the canister drawing fuel vapor from the catch tank via teh 3.5mm line. After being passed through the charcoal the return line delivers the fuel vapor to the top of the air box, post filter, ( which is why you should plug it if you do not intend to use the system) to be burned along with a the fresh intake charge.

wheew. hope that helps.

[dc914guy]

Scott~
That really does! Thank you very much!

~Eric

[ratwell]

Does anyone know where to get replacement activated charcoal? Please don't say the aquarium store. There has to be an inexpensive source that doesn't require you to buy a 55 gal drum.

[AZ914]

Scott,

I was under the impression that what you are describing was the 'fuel tank expansion chamber'. I have a charcoal canister back by my engine that actually clamps to the battery tray. I assume this has something to do with your description...

Thanks!

[Curvie Roadlover]

I'm pretty sure '75's and '76's (and maybe others) had the charcoal cannisters in the engine compartment. Some attach to the firewall and some attach to the battery hold down bolt.

[norustscott]

I must admit that my experience has been with the 74 and earlier version of the beast. 75/76 canister in the engine bay? anyone...

[Curvie Roadlover]

The charcoal cannister was mounted to the battery hold-down bolt on both the '76's that I have owned.

[scg]

Yup....that's where it was on my old car. Only one vapor line ran to the rear of the car through the center tunnel (expansion chamber to canister). No hard plastic hoses down the drivers side longitudinal...

The whole thing was attached to the battery tray...really hid the fuel injection "computer" well and made changing plugs a pain (cramped in there!)

[woodman]

Yeah, it's there in my '75. Love all the clunky extra crap of the late model.

[Dave at Pelican Parts]

Some 74s also had the engine-bay-mounted charcoal cannister. My old 1.8 had that, but my 74 2.0 has the cannister mounted up front by the fuel tank.

No idea where to buy the charcoal for the cannister.

--DD

[Clay Perrine]

In 74 they moved the canister into the engine compartment on the 1.8. 1975 and later the charcoal canister was in the engine compartment on all 914s. As for the canister itself, unless there is charcoal falling out of the canister, you don't need to replace it. It doesn't wear out. And if you do go to buy one, they have been superceded by a VW Vanagon canister, and the size of the canister and the hose fitting for the air inlet is different.

[bob174]

I recall reading a thread on this board about the cannister charcoal--do a search out there in cyberspace.

[nutzforporsche]

I still have a cannister laying on a shelf from a 74' I parted out. Never saw much reason to put in on my 73.....

[jamcleod]

up front near the gas tank in my 74 1.8L 4742908360.

need depends upon emission inspection and if the tech notices that one is supposed to be there.

dc914guy, contact me if you're dying to have one.

[bowlsby]

Early 74s had the canister in the front trunk. My 4742901465 (August 73) is this way.

Later 74s moved the canister to the engine bay. My 4742915176 (March 74) is that way.

The change happened somewhere in between those dates FWIW.

[scg]

Oh yeah... the line through the tunnel (on the ones with the canister in the engine compartment) is getting old and may crack, resulting in that great 91 octane smell...