Hello: I have a 97 Mercury 150 outboard 2 stroke E150ELUE. Basically a normal 150 outboard. Right now my stock volt meter will show 17+ volts when I'm runiing the motor, idle or higher, it'll eventually creep up to 18V. In my garage I unhooked all the accy wires to the batt, turned on the key (didn't start the motor) and the guage went to 17+V. I took a Fluke, put it on the hot post for the guage and put the neg lead on the stearing column and it read 14V or so(charger plugged in). I checked the batt and the Voltage was the same 14V. I unplugged the charger and waited. I checked the batt and it was stable @12.84V. I checked the back of the guage and it was also 12.84V. With all this, the guage still reads 17+V. Is the guage bad? Could it be anything other than the guage or could something else be the problem? The guage seems to run straight from the ignition switch. With the main power switch off, there are no electronics, lights, fishfinders, nothing. Only the motor and volt guage work with the main turned off. Any ideas why it's reading so high when the only power is a single batt reading 12.8V and not motor running?
