This might sound like a total novice question but does my late 70s 650 mercury recharge the battery by alternator or do i need to remove the battery every so often and charge it. I havnt ran it long enough to find out.
You should have a charging circuit. An easy way to see if it is working or not is to check the voltage at the battery with the motor off, then start it and as RPMs increase you should see the voltage increase.
