My waverunner will only go 17 mph when I first start it and go. If I open the throttle too much, it will shut down. If I press the primer plunger a couple of times, it will go faster and continue to run faster; BUT top speed is only goes 45 mph. It seems to run fine at 45 mph, but I know it should be able to go around 60 mph. I saw some gunk in the fuel filter, so I changed it out (still runs slow). I ran some brake cleaner through the ON/RES fuel valve and it seems to be clear of obstructions. I have not checked compression or anything else. Any ideas?