I inherited this 9.9. I'm using it primarily as a trolling kicker, so speed/RPM's is kinda important. I know the knob on the very front is supposed to act as a throttle position tensioner, cruise control, if you will. Well, it will just turn and turn, without ever tensioning. Has anybody had this problem, and was it very hard to fix? I'm thinking about just tearing into it, as I've found a schematic for it, but, would like to hear from anyone who's already tackled this.