Took my Yamaha F115 out for the first trip of the year and it's not running right. When you hit the throttle you don't hear the roar it normally has, almost like there is a muffler on it. It has a slight vibration and will tach out at about 4k (propped for 6k). Ran fine when I put it away. I pulled the plugs and number 3 was a bit wet so I replaced it, checked for spark and took it out again. Same problem. Any ideas would be great.
