I have a 2001 60 hp Yamaha on an 18' G3 CC boat, which normally scoots me along at about 30 mph. Last weekend when I took it out it would only go about half speed. It felt and sounded like it was bogging down. It runs fine on the trailer with the muffs on it, but not in the water. No other problems (starting, peeing, etc.), just getting up to speed in the water. Any suggestions?