79 Spider 32 adfa idle

[barnesjtsl]

Any idea what this screw is and how to adjust it? However I adjust it I either get a 2000 rpm idle, or it dies at idle.

Thoughts?

[18Fiatsandcounting]

That's the fast idle adjustment for when the choke is on. It should be adjusted for 1600 rpm or so, but only when the choke plates are fully (or mostly) closed. In other words, when the engine is totally cold. It should not be fussed with when the engine is partially or fully warm. Once the engine is fully warm, there is a separate idle speed adjustment for that.

If you search on the web, there are various Fiat or Weber shop manuals that run through the entire process for adjusting a 32ADFA carb.

-Bryan