My 03 Big Bear was starting and running fine at idle, but when I pushed the gas it would stall instead of rev.
I noticed gas leaking out of an overflow tube coming from the carburator. This tube has a screw where it goes into the carburator, I figured the screw might be loose and when I hit the gas it is leaking out of the tube instead of going where it needs to go. So I tightened the screw and then when I tried to start the quad it would crank but not start. I unscrewed the oil dipstick to check the oil and a gas/oil mixture came gushing out of where the oil dipstick screws in.
I dont know how gas got into the oil but it seems to me like it could be a serious problem.
Does anyone have any ideas, what the problem could be?

 

Stuck carb float. Pull the carb, fix the needle and seat problem, change the oil and go have fun.