I have a 86 150Gt VRO that the VRO has been disconnected on.I premix 50:1.When I first run the boat it does great,towards the end of the day.I was heading back to the landing I was tunning half throttle,I then decided to run it WOT after about 45 seconds of WOT a buzzer started going off from the remote.I backed off to half throttle and it went away.I nail it the alarm came back.I had a good stream from the water pump.The engine sounded good no back fire.or anything like that.Where should I start looking ..thanks Joey