Fuel in water?

[Chuckseders]

Hi all, sorry if this thread already exists. I have a 40 hp yamaha which appears to be leaking fuel or something. The thing is, it doesn't leak while sitting in my garage, but when it's parked at the dock I can see plumes of fuel or oil drifting away from the motor. It seems to be coming from the lower unit, but still, nothing draining while on land. I just had the lower unit seals serviced last season. Any advice/ideas will be appreciated.

 

[ClassicAQ]

Before you launch boat wipe down lower unit and back down boat into water so only the LU is submerged. Start engine and look for fuel/oil slick. If so, then you've narrowed down where it's coming from. If not, then leak is coming from mid section.