We have a 23 HP Kawaski FH-680V on a 2006 Wright Standar that has been working fine and close to 250 hours. We will likely use the machine only around 150 hours per year. So far we have only completed oil/filter changes, air filter cleaning and replacement, cleaning of cooling shroud and fins, and fuel filter change. Original spark plugs. Question is - what preventitave maintenance should be completed at 250 hour interval to make the engine last and perform best? Does Kawasaki have a web site describing the service intervals as the engine gets hours on it? What is the expected life of these engines with good maintenance.