OK help please, battery and charger questions

[sporters78]

ok searches done, still don't know the answer, many threads read.
boat is 2004 340 da that spends alot of time on the hook
kohler 7.3 gen
stock battery charger inteli-power model pd2040 (40 amp )
4-- group 27 delco batteries 1 3/4 years old (port one's are sometimes dead after being on hook. volts drop down after a little bit ,not much on )
would like longer time on hook without running gen or having dead batteries
thinking maybe if it would work switching the port side batt (port eng,house gen ) to sears agm work (what size? ) that work with my charger and not mess up starboard delco's?
BIG THANKS

 

[Nehalennia]

If I had your boat I would install one of these.
http://promariner.com/productFeature.php?ProductNum=63160

I have their Pronautic 1240i and it's worked very well and they have great customer service.

 

[sporters78]

update little , port side shows 12voits on voit meter inside but but will not turn over port engine... looks like new batteries for that side. with charger on shows 13.+ volts plus on port batterys

 

[timemachine]

You have 2 issues a small charger that depending on how low you bring your batteries down will take quite a while to charge back up and batteries that are about 80 AH each? I just upgraded charger so I get a larger charge in less time and I have big group 31 batteries. I may even add a third to the house.

 

[sporters78]

Timemachine,
what charger did u install and what type of batteries?

 

[northern]

On my 28 footer I had a 3 outlet charger insalled then an 1800 watt inverter. Each outlet on the charger put out 20 AMPS I ran two group 27 deep cycle batteres per engine. The battery switches allowed me to run the house with 1, 2, 3 or 4 batteries. I ran 3 and kept one to start the engines. It in now cheeper to install an inverter-charger. My present boat has a 2500 watt inverter with a 140 AMP charger. This puts lots of AMPS in the batteries in a shrt time.