A boat needs more than one speed

After a nice breakfast at a local restaurant I had the waste holding tank sucked dry and fuel added to the diesel tank. Then I pulled away from the dock enjoying the pleasant but cool air and fluffy white clouds. We rounded "Pound of Tea" rock and headed down Casco bay. The autopilot was working well. This allows me to do things around the boat while not having to be constantly at the wheel. One has to be careful and not take one's eye off the sea for too long. It is amazing how fast an obstacle can come at you. Near Bustin's Island my throttle stopped working. That is, it would move but the speed of the motor would not change. Something was wrong. I stopped the motor and put out the anchor. I looked at the motor but as it is in such a confined space and I had no one to move the throttle at the wheel; I could see nothing wrong. So I started the motor and headed back to the dock at flank speed as that was the only speed I had. Approaching pound of Tea I called the dock crew and suggested that they grab me as I flew by. It was suggested that such a capture was not in their best interest nor in the best interest of other boats at the dock. They suggested sending out a work boat to get me once I was in the harbor area. This worked well and the Windchaser is now back at the dock waiting for the engine crew to fix this latest problem. A fellow boater moved the throttle back and forth allowing me to see that the cable was working well and that a nut had come loose from the fitting where the cable attaches to the actual throttle on the engine. This position is almost impossible to get at because of the cramped quarters in the engine compartment. I believe that it is best to let the mechanics look at the situation as I might attach the end of the throttle cable to the wrong thing on the motor and cause more problems.