To vent or not to vent?

[johnsje6]

I recently put a 34ADF and an 1800 intake on my '79, and removed the 'extra' vacuum lines, carbon canister, etc. The question is, what to do with the fuel tank vent line? Do I plug it or should I somehow vent it or hook it to the intake? I have heard a sucking sound when I removed my gas cap before the modifications, so not sure if it was venting correctly then or not, these Fiats seem to have check valves in funny places sometimes.

Question #2 is fuel tank coating - I cleaned and coated my fuel tank with Red Kote, and the guy at the auto parts store said not to use Sta-Bil with it as it would react with the Red Kote and make it come off, creating a horror story in my fuel tank - can anyone confirm or deny this? Thanks! JJ.

[brackie1]

John, I can't help you with your question, but maybe you can help me. I have a '78 carb. Model and bought a 34ADF carb, but never put it on. However, now that I have broken off one of the screws that holds on my hot water choke control I want to install the new carb. But I don't know what to do with all of the old tubes and how to connect the electric choke. The new carb did not come with enough instructions. I am not a mechanic but could install it if I had good directions. Thanks for any help you or anyone else can give me.

[johnsje6]

My '79 had a dual plane intake, so I replaced it along with the carb. Now the only vacuum lines I have are the one to the distributor for vacuum advance, the large one to the brake booster, and one to the air cleaner. So my guess would be you can block off all the vacuum ports except those. As far as the electric choke - my ADF had a water choke, but I believe if you hook your electric choke to a wire that is powered when the ignition is on, it should work.

[brackie1]

Thanks.

[BEEK]

do not plug up the gas tank vent line. you can leave it terminating in the charcoal canister. but the 8mm line that goes to the tank from under the hood to the rear, do not plug. You do not have to have vacuum on the small line going to the charcoal canister. the fuel vent on the carb may not have a line like original, this means that the float chamber is vented directly to the atmosphere, this is also acceptable.

[brackie1]

There a a bunch of lines in and around the carb that I don't have a clue what they are for. Does any have any pics that show which ones can be plugged and which ones must operate?

Gene
North Carolina

[carl]

If you don't have a vacuum advance distributor and most if not all of your emissions devices have been removed you can chuck all the vacuum lines.

[brackie1]

Not being a mechanic I don't know how to tell if I have a vacuum advance distributor or not. When you wired the choke, where did you pick up the ignition switch wire or did you run a new wire to the switch?

[johnsje6]

Beek - thanks! That is exactly the information I was looking for, and pretty much what I thought, but nice to hear it from an experienced owner/mechanic.

Brackie1 - Look at your distributor, if there is a small hose going from it to your intake manifold, that is the vacuum advance line and must be connected. My carburetor has a water choke, so I did not have to find a wire. Honestly not sure what would be a good source for your choke - but has to be hooked to something that is only on when the ignition switch is on.

[carl]

For the electric choke, just use the wire that went to the idle stop solenoid on the stock carb.

[eugenel]

I plugged mine with a bolt, will remove it at the gas tank next. Make sure your tank is vented well at the tank. I believe the carbon canister line has a one direction valve on the line near the tank, so it's not doing anything for you. Make sure your vent lines didn't get clogged by redkote. I decided to stray from the cheap route and got a new tank from vicks for 120.

[brackie1]

Hey john, I do not have a vacuum distributor. So I'm good there. I wonder if I could pick up power from the head light wire or would that be too much for that circuit?