As you can see in this photo, which is not mine, the tab is not touching the "tower"/"perch" or whatever, but it should be. This limits the movement of the float and allows it to pivot properly on the pin. In the resting position as shown in the photo it should just be touching the perch. When the tab is not touching the perch there is a lot of slop and play in the float and it is very difficult to adjust the height using the tang in the middle that rests on the needle.
I am guessing this happens a lot when you bend the center tang by pushing against the float while it is resting on a flat surface; you end up squashing this tab. It bends back easily with pliers.
I am guessing this happens a lot when you bend the center tang by pushing against the float while it is resting on a flat surface; you end up squashing this tab. It bends back easily with pliers.