Carburetor issues

[jrearden]

I have a 1975 Fiat Spider 1800. I replaced a Weber 32 adfa with a 34 adf new carburetor in lieu of rebuilding the existing carb. It now tends to flood almost constantly. I have tried to adjust it to no avail. Any thoughts?

[18Fiatsandcounting]

My first thought is that the needle valve for the float bowl is not closing off as it should, so you might check that. Another possibility is that the fuel pump pressure is too high, although this usually only happens if someone installs a higher pressure electric pump. The nominal fuel pressure for these Weber carbs is 3 to 5 psi.

When the engine is idling, and if you look down into the carburetor throats, do you see any fuel spraying or dribbling out? If so, from where? There shouldn't be any visible fuel at idle.

When you say "new 34ADF", does this mean an original Weber, or a Chinese knockoff? The knockoffs sometimes work just fine, but some suffer from fatal flaws and they just can't be made to ever work properly.

-Bryan

[TheBender]

I just had a 34ADF European made installed on mine too. Had to change out jets and also adjust the float. They aren’t ready out of the box. As Bryan stated, I’ve heard quite a few people talk about an amount of fixing to do with the Chinese made webers.

[jrearden]

The 34adf is a Chinese knockoff.

[jrearden]

The 34adf talks about needing a single plane manifold, but from what I read the 32adfa already sits on a single plane manifold. Am I missing something here? Also, the fuel is dribbling in but I can't tell from where.