A couple of thoughts. First, make sure that all batteries are the same type - Flooded, AGM or gel. Second, a deep cycle battery is not the best choice for a starter battery. Deep cycles are just that, they provide a flow of power over an extended time, then get charged back up. Starter batteries are the same as car batteries. They provide a big slug of amperage to start the engine, then immediately get charged back up. Pick a good marine starting battery. If you do the house bank with 6v batteries they are basically golf cart batteries and are deep cycle.
Once you have all that house capacity, make sure that your alternator and regulator are up to the job of charging them. You'll probably need a high output alternator from Balmar with a smart regulator. The stock alternator is only 50-60 amps and has an internal regulator that limits its ability to charge a big bank even further. Not as big an issue if you are in a slip and can use the shore power charger regularly. On a mooring or for extended cruising, charging would become an issue.
You should also consider going to a Blue Seas battery switch system that isolates the house and starting batteries in conjunction with a battery combiner or charging relay.
On 11/30/07, brucep2100@... <brucep2100@...> wrote:
I'm thinking of changing my battery configuration from 2 GRP 24 deep cycles paralleled via a 1-2-all-off to 2 6V in series and a grp 24 deep cycle for a starter battery. I would appreciate any thoughts, suggestions, or experiences from the group.
I did look at Dick Coerse's web site which is often the first place I go for inspiration, particularly since my hull, #168, is close to Dick's. Dick, I see you switched to 2 6V batteries - anything special you had to do? I also see what looks like a 3rd battery in the compartment? Again, anything special you had to do to get it to fit? At first glance, it looks like the hoses from the engine to the hot water heater might get in the way?
Thanks for your input.
1982 Sabre 34 MKI #168