I have a 2000 Merc 9.9. Today I put it horizontal to the ground on it's bracket and locked it into place before taking it out fishing. I smelled gas so I put it back to vertical and took the hood off. I noticed gas coming out of what appears to a plastic pipe attached to the carb. I've included a pic of the carb and circled where I saw the gas coming out. It was about a shot glass full. Any ideas on what this is and how I can fix it?