charcoal filters?

[seancanfixit]

Hi, my 73 std has a charcoal filter under the bonnet coming off the fuel filler, as well as what looks like a spot for one inside the passenger rear wheel well, I'm just curious what everyone thinks of getting rid of them or plugging the lines, gutting the canisters and putting them back for looks.  do they do anything, or will it affect aircare, or any nonsense like that.  Thanks

[BUSDADDY]

Like most things VW puts on a vehicle it's there for a reason, without it your car will stink like gas whenever it's parked. Be careful about blocking off lines too, that's the only vent on a late fuel system. Keep it and replace all the rubber lines, Aircare doesn't care about it but you'll miss it when it's gone.

[Bruce]

What big benefit will you get if you remove them?

The can up front is not a charcoal canister.  It is just an empty tank. It's purpose is to provide room for expanding gasoline to go instead of all over the ground.  Then, the other end of that tank is your vent, going back to the charcoal canister under the rear fender.  There, the excess gas fumes expand into the charcoal.  Then when the engine is started, those fumes are drawn into the engine to be properly burned, instead of being smog.

[Randy]

I had a gas smell problem when parked because the lines to the charcoal cannister at the back (from the fanshroud & to the carb) had been cut when the dual Kadrons were installed by a PO. Until I have a better solution, I just put a plug in the line and it has seemed to stop the smell.

[BUSDADDY]

I had a gas smell problem when parked because the lines to the charcoal cannister at the back (from the fanshroud & to the carb) had been cut when the dual Kadrons were installed by a PO. Until I have a better solution, I just put a plug in the line and it has seemed to stop the smell.

Wait for a hot day with a full tank, things could get interesting.
drill a pipe fitting into the aircleaner base to connect the vent line to.

[Randy]

I had a gas smell problem when parked because the lines to the charcoal cannister at the back (from the fanshroud & to the carb) had been cut when the dual Kadrons were installed by a PO. Until I have a better solution, I just put a plug in the line and it has seemed to stop the smell.

Wait for a hot day with a full tank, things could get interesting.
drill a pipe fitting into the aircleaner base to connect the vent line to.

I will probably hook it back up similar to original, venting to one of the carbs. Thanks for the warning.

[kris urban]

i just cut mine off and left it  works good no problems and nothing wrong  there just extra weight

[BUSDADDY]

i just cut mine off and left it  works good no problems and nothing wrong  there just extra weight

Good to know, thanks for sharing. So....any other jewels of wisdom you'd like to share that the office tower full of of meticulous German engineers got wrong?

[Hansk]

Anytime we can keep some voc's out of the air we breath is a good thing so keep it hooked up. Also , apparently those charcoal canisters will last almost forever as long as they never get actual liquid fuel (or probably any other liquid)  , then they will no longer absorb any vapors.
I think that charcoal canister (at the rear) should have 3 hose's to it?  a small vent from the tank and 2 purge hose's ,from the fan shroud to the canister and from canister to air filter ?

[kris urban]

im telling you its just a pice if you want a stock bug if you want better performance just get rid of it and use K&N