I have a '95 150hp Mariner Magnum, EFI, it seems that my motor is discharging my cranking battery.<br />When the engine is off the in-dash volt meter reads about 11 volts, first thing in the morning. But, when I am running the voltmeter drops to about 10 volts. shouldn't it be around 14 volts when running? My battery will usually get to week to crank the engine after about 6 hours on the water. How can I check the output of the engine charging system?