I have a 2012 Bennington Pontoon boat with a 90 HP 4 Stroke Yamaha outboard. I have 22 hours on the boat. At about 14 hours when running wot or above 4600 rpms the engine will intermittently and without notice drop from 5000 rpms to approximately 2500, back to 5000 and back to 2500. If you...
