The activating coil in the solenoid is internally fastened to the positive battery post. Test the solenoid by attaching a jumper wire to the small terminal and touching the other end to the engine ground. That should activate the starter. If nothing happens, the solenoid may be in upside down. Try reversing the positive and negative battery connections, and test again. Still nothing – bad solenoid. If it just clicks, then the internal contacts are dirty. It is hard to take apart to clean, so best replace the Solenoid. The Super Quiet (Aquasonic) models must have a good ground strap (wire) between the mercury switch and the engine block. (Rubber motor mounts & plastic bushings insulate the engine from the tiller.) Make sure you have good tight connections. . . 😉
