Battery Noise

[Mid-Lake Rock]

I have a 24volt trolling system with an on-board charger. My batteries are Interestate and I've had them for four years. Lately, one of the batteries makes noise while charging. It sounds like something is boiling in the battery. Fluid level in the battery is good, as I just checked the level. Any ideas? Thanks.

[BobT]

When you charge a battery they will bubble and heat up. Make sure the ventilation is clear on the battery so the pressure doesn't build.

Bob

[theoilman]

If they both aren't doing the same thing you may have a problem in the near future - they aren't charging balanced and equally.

[Surface Tension]

What those guys said.

Sounds like both batteries are the same size.

I'd probably charge them separately and then test them to see if one has gone bad.