I'm having a great experience with the used '94 Yamaha 90 I bought last year. It is so reliable, it's scary. These are my questions to you old salts out there: 1) When on vacation for up to a week with the boat left in the water at a dock, is it necessary to regularly flush the engine with fresh water--as I normally do when I trailer it home from a days outing? Some of the places we go are very stingy with water(i.e., Fla Keys). 2)If it must be flushed at the dock each day, is it safe to use muffs on it and run the engine when it is tilted up? 3)When the engine is stopped for several hours, does it matter whether or not the lower unit is tilted up, or left immersed in the water? I'm posting in the Yamaha column in case there are any Yamaha-specific answers to any of these. Thank you.