Finally resolved my boat's inability to reach wot speed and rpm range with a distributor cap cleaning and fuel separator installation. What I now am trying to figure out , is why after reaching 4200-4600rpm and running for 15-20 sec., the engine will all of a sudden adjust back to 3500 rpm. What I did find is that if I adjust the adjust the trim to a certain location--approx 1/3 to 1/2, I am able to sustain 35mph and 4200 rpm and cruise the lake. Any ideas. Thought of some kind of rev limiter or limit switch somewhere?