Small Engines (Lawn Mowers, etc.): gas leaking from Band S engine, briggs and stratton, gas leaks

Question
Hello Michael
I have a Colmen Generator with a 10hp Briggs and Stratton engine driving it(Modle 19G417).  When the engine is stopped and the gas shut off valve at the gas tank is on, gas leaks out of the carburator.  It is coming from a 3/16 in by 3/16 in high copper tube just behind the choke flapper of the air intake part of the carburator.  When I turn off the gas tank valve it stops.  I don't think it should leak like this and something is not working right. It can leak so much that in a few hours the floor around the generator is covered with gas. Not a safe thing. Can you tell me what is wrong and how to fix it?
Ron Swaim

Answer
Hi Ron,

I suspect a leak in the carb's float assembly.  Remove the float bowl and look for debris holding the needle valve open.  If that looks okay, you should replace the needle and seat.  Also, check the condition of the float.

Let me know how you make out.
Michael