Batteries for AJ 290

[ah64a]

Hello guys,
I have an AJ 290 and I have been having a problem with my batteries. I bought the boat last year so I don't know how old the batteries are. I kept the shore power hooked-up all winter and the charger on as well. Are all batteries (3) being charged? Do chargers need to be replaced? What is a good one to replace the original with? What batteries should I use? I believe right now I have two normal batteries and a deep cycle. I believe two are for starting and the other, I am not sure. (sorry for the ignorance, i am learning) Do you keep the two batteries swithches on ON or OFF when charging?

 

[wingless]

There are three ways to quantify the battery health. All involve testing a rested fully charged battery that has sat on a charger for more than 24 hours and then sat idle for at least a day.

The best way is to use a Midtronics Battery Tester. This is safe and accurate. It will quantify all the important parameters about the battery health.

Any retailer that sells batteries should have this tester on-hand for performing this test.

The second best way is to conduct a run time test. Apply a load that would fully discharge the battery capacity in 20 hours and measure the run time. I use my 'fridge for this test.

The third way, that is fortunately going the way of the dinosaur, is a high-current load test. The voltage is measured while discharging under a short-duration load.

 

[Redhook98]

I noted that when I got my AJ, the batteries were bad. They were actually cooked by the charger that was installed from the factory. It was a Flyback 20-3 or something along those lines. I replaced it with a Xantrex Truecharge 40+ with remote panel. Then I replaced all three batteries with Group 27 Deep Cycles. I did not feel the need to install starting batteries instead as small blocks with fuel injection do not need a lot of cranking to get started. Never had a problem since then.