Attached to the float bar there is supposed to be an item called a torsion spring. I am rebuilding and I see this is missing from mine, and not in the Auto Zone kit. Wonder if this has been the reason for bad mileage and fuel smell. At any rate, where do you go to get something like these springs?

...You can always try Pony Carburetors. The only problem there is that they have a $50 minumum.

They really aren't springs, they are float retainers. At least on my 4100 the only thing they do (and it is very necessary) is keep the float tab centered over the needle valve. Without it/them, the float would slid back and forth across it's pivot shaft and not put square pressure on the needle.

I suppose you could do the same thing with small stainless steel circlips that you could get at the local hardware store. The shaft has groove in it to accept the spring end and I am sure you could find circlips to fit those grooves.

I am really surprised that no one else has addressed your post. This site is really dead lately.

regarding those springs as well. I'm in the process of rebuilding my 4100. When I pulled the air horn I noticed my springs were just sort of dangleing on the float hinge pin, not really doing anything. The kit I have call them "spring, float dampner(s)". I assumed they are somehow needed to dampen the floats going in a up/down possition. I looped the short end under the float hinge (it points in that position anyway) while the longer end tucked back to put a slight up load on the float.

Now I don't dought they may be needed to hold the float in place, but wouldn't the float retainer thingy keep the float from moveing back and forth and posibly shift away and off the needle and seat assembly?

I just went out and played with my 'springs'. There is no possible position for them that could put any pressure on the float or arm, to act as a damper. The main part of the spring itself is nothing more than a handle to enable you to snap each end of it into one of the pivot shaft grooves on either side of the float tab. There are 4 grooves in each shaft. Two out at the outer edges and two spread across the center. This allows the pin to be used without orientation. The float slides on the shaft, the spring clip ends snap into one of the outer grooves and one of the center grooves, firmly keeping the float from sliding back and forth across the shaft. The springs do the exact same thing as would two circlips without the hassle of trying to hang onto the itty bitty individual circlips.

The question relates to the torsion spring(NOT the float retainer) which is supposed to exert a slight upward pressure on the float, as the one poster described. It's long end bears against the wall of the float bowl, while it's other end engages the float. I suspect many guys on this site have never seen this part as they tend to get lost during the carb's first rebuild. I was recently at a local Pick-a-Part and found one of these rare babies just the other day. I only need one more...
Werby posted a while back about a possible high float level/flooding situation he was experiencing, but I had forgotten all about those little springs and therefore failed to mention them as a possible solution...until now.

As I mentioned, my springs were just dangling on the pivot shaft and not used to lightly lift the float up. I just assumed while rebuilding that the previous owner didn't know how to re-install them.

Anyway, I slide that end of the spring under the float lever hinge to dampen the up and down action. Hope it works better when she's back on the road.

I always try to use the torsion springs (tho I have run without them and not had trouble)

I wonder if the torsion springs help when there's a lot of vibration or rough idle, otherwise the float would keep jittering open and let the fuel level come up too high?
So maybe with a very docile idle they are not needed?

In the flooding-plagued carb, the torsion springs were on there. The only thing I can figure is I had two floats in a row that were not pushing down squarely on the needle valve (and also had a couple sticking needle valves). Combination of kinda rare problems, all at the same time.

I set up four other 4100s during the next few weeks, no flooding issues with any of them. I think that one carb is haunted. Runs great, it's just haunted, a poltergeist or something.

if you got that flooding problem fixed. Sounds like the float valve seats might be slightly distorted from over-tightening? Don't think I believe in the supernatural...at least not in carbs...but who knows? Where do you find the time to accomodate EVERYBODY'S Gonk request? Me thinks you created a monster with that...