I have now determined that the Yanmar engine operation manual recommends an initial 50 hour maintenance. The maintenance is very extensive including adjusting the valves. In addition, the tension on the alternator/coolant pump is suppose to be adjusted to 8-10mm. After, my service was performed(I was charged for the service but most of it was not done the first time and then was done after I complained to North America) the engine overheated. The tension for the alternator/coolant pump belt was too loose and the belt for the seawater pump was even worse. The manual does not indicate that the belt should be checked or what the tension is suppose to be. North America indicated that it should be 5-7mm. So, now I am hoping that the third time will be the charm. This servive was provded by the exclusive distributor for Louisiana, Texas, Oklahoma, Arkansas, Alabama and Mississippi. I have learned that while this place is an exclusive distributor, they are not the exclusive dealer. I need to find a reputable dealer and others should be warned that the operation manual has left out the procedure to adjust the tension on the seawater pump. Anyone know of a reputable dealer in the Slidell, LA area?