Motor leaking fuel

Just noticed this last outing, but after running the motor, and shutting it off, it leaves a pretty good trail of fuel in the water. I'm not sure why, my motor is newer and runs fine. I did have the lower unit replaced last year, but don't know why this could be happening. Has anybody ever had this happen? Where should I start to fix this problem? All lines are connected fine with no leaks in them, fuel filter is new this year.

I had a fuel line crack where it goes to the carbs letting gas leak into the water once might check them to make sure they,re not hard and cracked.