Maybe someone can help me. My 1996 sugar sand heat's Mercury sportjet 120 starts and runs Excellent until about 80% or more throttle is applied then it still runs good but engine changes sound a little and does not rev any higher and the boat does not go any faster. If I back off the throttle a little it runs excellent again. It just started doing this the other day. Before that I could go about 38-41 mph full throttle with just me aboard. Now at full throttle I can only go 30-33 mph. I am calling a mechanic on monday but maybe someone has some advice. Thanks
