The idle speed control just in front of the kill button is not working. When I turn it , it just turns and clicks. The throttle arm on the carburetor is not moving either when I turn the control. I like to adjust my idle speed for trolling. I'm good at .8 mph at slow idle, but when I try to throttle up it goes to 1.8 mpr. I can't get to the 1.3 to 1.5 mpr which is my preferred trolling speed. I'm afraid the linkage inside the tiller arm is broken. Anyone know if there is an easy fix, or do I need to replace the entire tiller assembly?