I have a 27 cranking from Wal Mart for my big motor and 'toys' as HaleDamage said. It's a year and a half old. I've never had a bit of trouble cranking my motor over, but when I troll at idle for a half hour or so, the voltage goes low enough to shut my Structure scan off. I luckily switched my structure scan (LSS-1) module so I can shut it off and still run my regular sonar and GPS. Any thoughts on what is going on? It seems to help a little bit when I shut my radio off and keep my livewell pumps off, but it will still drawn down low enough. When I go faster than a trolling idle, I draw enough volts/amps to run everything. Do I need a bigger/better battery? That's the plan first thing next year unless someone else has any other ideas.