Battery charger

[stanleyi]

Both the house and starting batteries on my hunter Cheribini read between "fair" and "need recharging". This was after replacing both batteries in the last few months. They are both Walmart marine batteries identical to the ones I replaced. Walmart tested one and said it was fully charged and good. Obviously different than what my multimeter says. They start the engine fine and getting no other indications of a problem. Should I trust the Walmart batteries? Could there be a problem with my on-board charger? No idea how to test that.
Thanks,
Stan

 

[Don S/V ILLusion]

"Fair" and "needs recharging" are not very precise terms.
There is way too much already written both here and generally on the internet to reiterate that which you can easily find by looking for explanations of how to test, monitor and charge batteries.

Maybe someone else will take the time to write their version but if not, do a bit of searching in the archives or elsewhere.

If you fully charge/recharge your batteries, maintain them properly and don't draw them down too far, they should last years.

 

[artboas]

Multimeter not correct tool

Both the house and starting batteries on my hunter Cheribini read between "fair" and "need recharging". This was after replacing both batteries in the last few months. They are both Walmart marine batteries identical to the ones I replaced. Walmart tested one and said it was fully charged and good. Obviously different than what my multimeter says. They start the engine fine and getting no other indications of a problem. Should I trust the Walmart batteries? Could there be a problem with my on-board charger? No idea how to test that.
Thanks,
Stan

A multimeter does not give you adequate status of a battery.

You need a hydrometer to measure specific gravity of the electrolyte