If it has suddenly gotten rich, it's probably not a jetting problem. Chances are you've got a leaky needle valve/seat assembly, or a float that has gotten some gas in it and can't seal the incoming gas well enough to keep the fuel level in the float chamber correct. A high fuel level will result in a rich-running condition. You could also have a sticky power valve that's letting fuel bypass the main jets. Either, or both conditions will make the engine run very rich and use lots of gas!
Jerry
