Is the carburetor the adjustable carb, or non adjustable?? The adjustable carb will have a fuel metering screw with a nurled outer edge so you can turn it by finger, and has a spring locking it in place.. If it's adjustable all you have to do is screw that screw out a little bit, it will pull more fuel, and make more power..
If your carb is NON adjustable, the fuel screw will be a brass jet, predrilled for the size that Briggs says it should be.. It just screws in tight and there it is forever...
Sometimes, you can LOOSEN that jet up like a 1/3 of a turn, and that will cause an internal leak.. That helps if you can make it work just right... YOU HAVE TO!! destroy the threads, or fill them with thread locker or silicone or something, because if the jet is loose, it will just vibrate out and get lost...
I'd recomend silicone..... Screw the jet out a few turns, wad some silicone around it, screw it back in till it's tight, then back it off JUST a litle bit.. THEN rev it up and see how it sounds... Not enough, screw it out a little more... If it starts loading up screw it back in...
It was never meant to be an adjustment.. and it will go from working right but running lean, to leaking JUST A MOLECULE and running good, to a BIG leak and loading up and running like shit, all in a real tight spectrum... maybe 1/2 turn out from tight, and thats too far.. you're talking 5/32 or 11/123 or something goofy like that... Just exactly in the right spot, 1/3 out from tight, can save you buying a new jet sometimes....
Just remember to goober it up so it doesn't fall out.. :mellow: