After winterizing my 2000 Mercury 90 hp motor last year, I started it with muffs in the drive this spring. All went well. I put it in the water the following weekend and could not get the same speed or rpm's I got last year. I had a full tank of gas that was stablized and the motor fogged. Starting the motor in the drive was fine and in the water. My problem is I can only get about 4000 rpms now when I could get about 5200 rpms last year. Any ideas how to recover lost rpms's, plugs, fuel filter, ???<br />Thanks 
