Float Chamber Overflowing.

It is circular but is more horseshoe shaped and lays flat rather than two floats side by side as in the illustration above.

Thats the one

hi, the spring loaded end of the shuttle should point down, i had same problem, over flowing carb, i cleaned the shuttle with a fine wet and dry paper, so it drops very easy and closes like wise, other than the shuttle its float level issue, that is trial and error really, you need enough petrol to cover the jets but not enough to over flow