carb bowl drain leaking?
Does that carb's drain use a pointed screw? If the drain is actually leaking, a mechanical fix should be obvious, like tightening the screw or cleaning it's tip.. or it might be to replace the screw's tiny O-ring, assuming there is one.
But take a close look at the drain. On some carbs, inside the float bowl there is a thin, vertical overflow tube and the drain channel at the bottom does double-duty as an overflow. When fuel level rises above the top of the overflow tube, fuel is channeled down to the drain and drips from the drain tube.