I have cleaned the carb, changed the float needle and o-ring. When it is running fuel still leaks out the drain. Could the 3130935 SCREW wore out and be the issue

 

Easiest way to tell is just take the bowl off,fill with fuel. If it leaks,then possible the drain screw may be not closing off the overflow. If it doesn't leak,then probably float level is still off. Plus may help to read this on the BST40 carb. Float height is critical as many have the same problem. Carb is similar to yours on the float adjustment. The BST-40 Bible - ADVrider
Float tab should just be touching the spring loaded pin on the needle when turned sideways. If the float isn't parallel with the body at this position,slightly bend the tang to where it does.