I have a 19ft bowrider bayliner 3.0l I/O. When i remove the canvas cover on my boat i smell gasoline fumes. i dont have any gas leaks in the engine compartment. I looked (as best i can) around the tank and still see no signs of fuel. I'm assuming if i had a leak i would see fuel somewhere. The only thing i could think of is that the boat cover - covers the vent. Any ideas?