Mine started this tonight....the first fill up after replacing the fuel pump (which runs like a dream now
). Anyway, when I got underneath of it and saw where the gas had spilled out it left a wet stain right in the middle where the plastic screw top is to seal off the fuel pump. Willing to bet its not tight or missed a thread on the way down. I used a flat head and a hammer on the last few bits of torque to get it tight but kind of *****ed out after a few whacks being that its plastic.
My advice is safely generate the leak and respond quickly to identify where the leaking gas leaves a wet stain if applicable. This will give you an idea if its a filler hose, cap, line etc.