Hello. I'm working on my 1976 124 Spider, that hasn't been started in decades, and would appreciate some advice to help point me in the right direction. I'm replacing fuel and vent hoses. The charcoal cannister was removed at some point (I found it in a box), and those lines were left open. So I'm figuring out how to refurbish and remount the cannister, and replace/reconnect those lines. Additionally, I am considering replacing the Weber 32 ADFA (the throttle body has a problem) with a 32/36 DFEV, which seems to be a recommended replacement carb in some of the posts I've read. I understand the new carb doesn't have a fuel return line. In that case, would I simply plug the then open return line that goes back to the sending unit? If so, I'd probably cap off the hard line somehow, and cap the return at the sending unit, since the nitrile hoses on either end are shot anyway. Thanks for any advice you can provide.

I've seen posts about cutting open the charcoal cannister and replenishing the charcoal with fresh activated stuff from a pet store that sells aquarium products. You can also retro fit the newer square style cannisters too.
If you go the DFEV route for a new carb, you can by a fuel filter that has a third nipple on it where you can attach the old return line that used to fit onto the return line nipple on the ADFA.

I found some instructions on refurbishing the vapor canister like you mentioned, so I thought I'd try it and see how it works out. If not, I'll look for the square style.

I like the idea of keeping the fuel circulating, at least I understand it helps keep the fuel cooler, so I'll look for the filter with the third nipple. It may come down to whether I can source fuel hose the right size. I've been struggling to find 30R9 hose that fits the various sized lines and connections in this project. Trying to connect to the two other hard lines, 1/4 inch is too tight, 5/16 seems too loose, and I haven't found anything in between. I'd guess that a true 7mm would be about right, but so far, I havent found a size like that. If I remember correctly, that return line is smaller than the other hard lines, so maybe I'll have better luck there. So far, nothing has been simple with these fuel lines, but that does keep it interesting and challenging. Thanks for the suggestions and advise, I appreciate it.
Mike

You're right, the Fiat fuel lines are in metric, 7mm OD for the smaller return line and 8mm for the supply line. Usually the fittings on the carb are similar. I've been using 1/4" for the 7mm and 5/16" for the 8mm, and it seems to work fine. The trick with the smaller size is to put a small touch of oil or grease around the nipple on the 7mm metal line, and the 1/4" hose should slide on. For the larger size, a good hose clamp is part of the solution.

-Bryan

Bryan, it's good to know those hose sizes worked. You've confirmed what I was beginning to suspect, that my option will be to make some connections that feel a bit loose and rely on the clamps to keep them tight. And I'll give the grease a try, too. Maybe a little petroleum jelly would do the trick.
Thanks for the info.
Mike

MikeInTN wrote: ↑Fri Mar 28, 2025 7:03 amMaybe a little petroleum jelly would do the trick.

Any lubricant would work. Oil, grease, petroleum jelly, etc. Just a small amount to help ease the rubber hose onto the fitting.

Warming up the rubber hose also helps a bit.

-Bryan