What is the correct, Yanmar approved maintenance schedule for the 3JH2E diesel engine? I live in Atlanta and my boat is in St. Pete where it is being 'maintained' by my dealer, however other than oil checks/changes and transmission oil checks, I am not aware of any other routine work being done to the engine. I have noted in the engine manual that there are places for service stamps to show the engine has been routinely serviced. They also mention things like periodic fuel timing adjustments etc. Are these 'adjust as needed' items, or should they be done according to a pre-determined schedule? Also, I noted in the engine manual that the fuel tank should have been drained after the first 50 hours. What is the purpose of this? Should this have been done by my dealer as part of the warranty maintenance? I like to keep my boat in top shape and I am always concerned when it appears there is no planned preventative maintenace schedule established.