OK, don't throw away the carb....
I had the same issue -- genny would hunt and surge like crazy.
Brought the carb to a small engine shop who did a full soak in an ultrasonic cleaner from Saturday to Monday. Between the vibrating and the long soak, it's been running like new ever since.
(on edit) The cleaning cost me $30. A new carb was over $200 at the time. Now there are knock-offs that are under $70, so it might be cheaper but I'd rather have the clean original OEM carb than a knock-off which may or may not work as efficiently.
