motor charging question

What is the easiest way to tell if your motor is charging the battery.It is a 85 - 115 mercury.Thanks in advance.

I would guess a voltmeter would tell you if there's current coming from the motor. If there's juice, then you can focus on the battery.

Put a volt meter across your battery when the motor is running and when it isn't. Voltage should be above 12v when the motor is running, depending on the state of charge. If the battery is low he voltage may be as high as 14V.

I have a built in meter and it should be around 13v if I not mistaken, anyway thats what mine usually runs.