I've been having problems with my wheeler, 2000 Yamaha Big Bear 2x4. First gas sarted pouring out some hose at the bottom of the float bowl on the carb, then the battery died so I thought I would change the filter while I was at it. When I opened the filter box it was about 1/3 full of gas. WTH? After getting the gas out and charging a new battery I started it up, revved the engine and turned it off. Gas poured into the filter box from the supply air tube via a hose that connects to the side of the cylinder head. Can someone explain to me what is going on?

 

Float in your carb is either stuck or sunk. Carb filling up with gas and out the overflow tube. If bad enough, it can back up into the airbox. Pull your carb and clean it out good.