mine was doing that until i started turning the pingel valve off every time BEFORE i shut it down and leaving it off until after i have cranked it the next time...i think that gas was slowly leaking into the cylinders and flooding it...in fact, it sat for about a month or so during the winter with the gas valve open and completely flooded both cylinders to the point neither would turn over until i got all the excess gas out (they call it "hydraulicing" (sp??) or in other words trying to compress liquid---won't work)...BEWARE however, remember to turn the pingel back ON after you start it the next time, before you run the carb bowls dry, or you will have H__LL starting it again....dbr