I've got a 60 hp mercury that the warning horn is sounding continous when the key is turned on. It sounds with the key in the on position and it does not stop when the motor is started. If I remove the oil sensor switch from the oil tank it shuts off? Any ideas or suggestions would be appreciated. The motor is not hot and the oil tank is full. I thought that maybe the overheat sensor might be faulty, but why would the horn stop with the oil sensor removed from the oil tank? thanks in advance 