I am a total rookie boat new owner. Bought what I think is a great deal but after 6 hrs of run time experienced a major vibration at higher speed. Throttled down and it actually kept up while in neutral for a few minutes. Didnt happen again that day. Went out again two days later to investigate a bit and everything seems fine until I throttle up. accelerates fine for a few seconds and then feels like it slips into neutral or something. Rpm's still up but going nowhere. Help appreciated. Would like to take my ten year old salmon fishing. He is very disappointed this weekend.