Hi Donglai, My thought is that you laid the Honda on the wrong side during the winter; therefore the oily smoke when you started running the engine. On one side of the engine case there are two feet. These are the feet that should be down supporting the engine when it is lying on the ground. 1. Check the oil level to make certain that the sump still has the right oil level, and refill if necessary. 2. If the engine ran fine the remainder of the afternoon, then it probably was burning off the residual oil that you had in the system. It doesn't take much oil to create the oily smoke you saw. 3. I'd also check the condition of the spark plug. If it got oiled up, then you might have troubles trying to start the engine next time you're out. If you have any doubts about it's condition (cleanliness of porcelain on center electrode); then replace it. It might not matter, but it helps the uneasy spirit when you "know" that you have a clean plug in the cylinder; .... and always carry a spare spark plug in your tool box - just in case... Glad to hear you had a great first trip. The first voyage is always the most difficult. That's when you are learning how to do it; where do things go; and how does it work; and you are learning how to step the mast and rig the boat. Next time you make new mistakes, but you are learning, and won't repeat them on the third outing. By then you are a pro. Have a great summer, Ciao Connie