Battery on boat keeps losing juice

The battery on my 1962 starflte Iv evinrude 75hp keeps dying out quickly. After recently replacing the battery, and starting and testing the engine a few times the battery died out. This has happened frequently, it starts out fine and then while out on the water it won't start up quickly. After attempting to start it up a few times the battery dies. Can't figure out the problem? Any info or advice would be helpful!

Re: Battery on boat keeps losing juice

you might try checking the battery cables, could be loosing juice thru a improper ground. Make sure all connections are clean and throughly seated.

Re: Battery on boat keeps losing juice

The first thing you should do is take a voltage reading of the battery at the battery terminals, with the key switch in the off position. Your battery should read 12VDC or more. <br /><br />Next start the motor, and again take a voltage reading. You should see a higher voltage at the battery terminals if the charging circuit is working. If the voltage is the same as when you tested it with the motor off, then your charge circuit OR connections are at fault. <br /><br />If the battery (I assume we're talking about a new battery) is losing it's charge (low battery voltage) after it sits for awhile, I would look for a current draw while the key is in the off position.<br /><br />Disconnect the B+ battery cable, place an ammeter in line between the battery cable end and the battery post . This will show any current draw while the motor is off. Pull fuses or disconnect wires from the connector block, one at a time, and watch for the meter to drop to zero amps. The wire that, when disconnected, makes the meter drop to zero volts is the source of the excessive current draw and killing your battery.