If it's what I think you're talking about, that spring basically attaches the inlet needle to the float plate. <br /><br />The other day I had surging problems and people tell me it's because I 'deleted' it when I put the kit in.
It's only real function is to pull the float valve open if it would otherwise stick. As long as the valve stays clean it should work okay. But sooner or later it will try to stick shut. It lets gravity do a lot of the work. Other forces that act on it are it's own weight (which isn't very much) and fuel pressure (which isn't very great considering it's tiny surface area). But the weight of the float and the leverage it provides dwarfs the other forces.
