I have a brand-new grand Banks currently being commissioned- it has
8D AGM batteries. The starting battery has been slowly discharging -
it has been at 11.9 V for the past 10 days and is now down to 11.8. I
have tried to alert the yard to this problem and they say they will
get around to fixing it (they say it's the charger- although the
house batteries are at 13.5 or so over that same period of time and
are being used). So I am concerned that the starting battery has been
permanently damaged. I would appreciate any opinions about this and
ideas about how I might test for this possibility. I'm assuming that
the yard will put a charger on it eventually and, while connected,
will show normal voltage.
I would appreciate your thoughts on this.

Bob wrote in news:ddf567aa-f148-4870-8e36-
:

So I am concerned that the starting battery has been
permanently damaged

You would be correct. That battery is permanently sulfated. It's lead
sulfate ions have long since turned to crystals, never to return.

Just replace it and try not to cry.

Jack Erbes wrote in
:

And I'd really be interested in figuring out what is draining the
battery.



Leaky diode rectifier in the alternator....It may not even get warm.

Jack Erbes wrote in news:47dedd5e$0$12570
:

Do you really thing that pulling a battery down to 11.9 Volts means it
is permanently sulfated?



Not if it's recharged within a day or two. But, left for weeks while some
boatyard screws around letting it lay there in a discharged state like this
with a NO LOAD voltage of 11.8VDC, yeah, it's gonna be hurt. The longer it
goes on, the more it gets toasted.

I don't want to depend on a yard-toasted starting battery, do you?
Starting the diesel in a timely manner with great reserve, just in case it
needs priming or more than a touch, is a very important task....as the wind
and current push it into that $1.2M superyacht owned by the law firm of
Diaphram, Foam and Condom, LLC, who haven't lost a case since 1962.

Yeech...no thanks!

As you cannot tell the REAL condition of an AGM battery, even the day you
bought it, the chance to hear that groan from the starting motor just isn't
worth it....followed by an eerie silence when it should be making a loud
knocking noise causing billows of white smoke from cold cylinder wall
condensations.

That battery's fine if he can cross-connect the house batteries to crank
it. But, most boats aren't setup with jumper cable switch banks, like
ours, that can make the starter cables JUMP if the beast kicks back...(c;

Larry wrote in news:Xns9A6469E071372noonehomecom@
208.49.80.253:

Jack Erbes wrote in
:

And I'd really be interested in figuring out what is draining the
battery.



Leaky diode rectifier in the alternator....It may not even get warm.



Or he could have a Standard Eclipse Plus VHF radio where OFF only turns off
the main PC board, not the damnable RF power brick that was conducting 3A
of DC, 24/7, heating up its heat sink and killing MY battery....damn them.

The real way to make this determination is to use a computer based battery
tester. Most everything else is at best a guess.

Don Dando


"Bob" wrote in message
...
I have a brand-new grand Banks currently being commissioned- it has
8D AGM batteries. The starting battery has been slowly discharging -
it has been at 11.9 V for the past 10 days and is now down to 11.8. I
have tried to alert the yard to this problem and they say they will
get around to fixing it (they say it's the charger- although the
house batteries are at 13.5 or so over that same period of time and
are being used). So I am concerned that the starting battery has been
permanently damaged. I would appreciate any opinions about this and
ideas about how I might test for this possibility. I'm assuming that
the yard will put a charger on it eventually and, while connected,
will show normal voltage.
I would appreciate your thoughts on this.