Looking for some advice. Here's the scenario. When full throttle boat goes on plane runs fine for about 40seconds then just drops off plane doesn't stall out just seems like i have a cylinder or 2 dropping out. I checked fuel prime i am not losing fuel bulb is hard and by choking when this problem occurs it stays the same. I go back to neutral open throttle back and its on plane full speed 40 secs and same thing keeps occurring. A while back i had a big loss of power all around was not cutting out like i have now. I had a new powerpack installed new plugs and wires coils were checked and said to be fine. Since then i am experiencing the cutting out. Can this be thermostat issue carb issue? I would like to rule out as much i can on my own before taking for service. I feel confident its not a fuel pick up issue because i am not losing prime and when it boggs down supplying more fuel does not solve the problem. Any advice would be great.