Batteries and shore power

[gard500]

I have a 1995 Sea Ray 290. When I am done for the day I always reconnect the shore power (120V, 30A), turn off the battery switches, and turn on the shore power main and AC converter. There are 3 maintenance free, Group 27, batteries. One for the port engine, and two for the starboard engine and house power. For one reason or another the house power batteries now only have about 10volts and won't charge further. Are these just bad batteries or am I doing something wrong?

 

[top*prop]

how old are the batteries? it is possible that hte battery is bad. the port side battery is also the house battery which powers your 12v lights etc in the cabin and cockpit, but if the batteries are 2-3 years old it is possible that the battery is bad

 

[gard500]

I am not sure how old the batteries are. We just bought the boat in December and did not get any service records for the batteries. The tabs on the batteries are not marked either. We did just determine two of the batteries to be bad though. They just won't hold a charge anymore. We plan to replace them this weekend. Thanks for the advice.

 

[Kevin Smith]

Battery Question

Each cell in batteries produces 2 volts, so the problem with your battery reading 10 volts is very likely one shorted cell. As the battery ages material can flake off the plates. If it builds up in the bottom of the battery it can short out cells.

If the batteries are older than 2-3 years they should be changed. It is cheap insurance to help avoid any starting problems while out on the water during the regular season. I personnally like to change mine every 2 years.

Kevin Smith
Richmond VA
1991 250/270 Weekender, 454CI, 330 HP, Bravo II