[C320-list] RE: AGM batteries, Battery OFF/BOTH

[Joseph A Tamucci]

John, thanks for your input on the AGMs.  I googled the AGM issue and
everything I've read about AGMs indicates their charge/amp hour performance
is as good or better than the standard flooded cell.  The AGMs are superior
in that they are 1)sealed (maintenance free) and don't lose water (no need
to check water levels anymore) 2) Have a slower discharge rate over time.
That's important if you leave your batteries on board all winter or are at
a mooring  and can't plug in at the dock) and 3) won't freeze and be
damaged over the winter (I'm up North). Given those considerations and the
effort required to replace the 130 lb excides from the boat, I'm still
leaning towards spending the extra $150-$200 per battery. I do expect them
to last longer although I haven't read anything that explicitely states
they will.

On the subject of 1/2/BOTH, I never ran BOTH but alternated between
batteries to assure that I had the other battery in reserve for starting.
Since then I've paralled both 4Ds as the house battery and installed a
dedicated starting battery so now I have twice the amphour capacity and a
battery just for starting.  In addition I also bought one of those
emergency battery packs from Walmart (highly rated by Practical Sailor) for
about $50.  It's small and only ways 30lbs or so and provides an additional
reserve for starting the battery.  Last summer when my 4Ds died, as a test,
instead of using my starting battery, I clamped on the battery pack to the
4D terminals and jump started the engine no problem.  If you don't want to
go through the efort of installing a dedicated starter battery, it's a
cheap battery backup alternative that works.

Joe #619