Re: 200 hp OX66 - how to know how many hours ?
how old is the motor? It's on the plate. or if it was original to the boat, how old is the boat?
200 hours is not a good sign on a 10 year old motor but not the end of the world; it's better if they are run. There are a lot of boats that don't get used much, even on the coast. The further north you go, the less use. Gas prices also affect the use; that one would use a lot for a family going tubing on Saturdays.
2000 is not that bad for Yamahas, either; the sport fishermen around here do that a lot (long runs to the fishing grounds + lots of trolling). Unless it's in a couple of years, indicating commercial use.
The owner's manual refers to maintenance at 100 hours/1 year which leads me to assume that Yam expects that average. To me, 200 hours/year is ordinary and notrhing to worry about--so a 10 year old motor at 2000 hours is fine IMO.