Is their an o ring that controls the flow out of the bowl
Please don't over tighten that screw... Bad things will happen.
On the 2001 and newer carb, there is no o-ring on the drain screw.
The drain screw serves 2 functions on the newer carbs.
The end of the drain screw plugs the hole for draining the bowl.
Secondly, it allows fuel from the overflow tube to drain around it.
When you remove the screw, you will notice a thinner neck near the end of the screw.
This leak notifies you that you have a leaky float valve or, more likely, the o-ring on the float valve seat is bad.
To fix either, you will need to remove the carburetor to fix the problem.
This is the result of a bad valve seat o-ring:
This is what needs to be replaced: