[C320-list] battery / charger issue

[Chris Descher]

I really appreciate all the help on this.  Here's more information.

The air and water temperatures are in the mid 70s.  My engine's got 270
hours.  I have the OEM alternator.  I have two batteries:  A 4D is on
battery 2, and a cranking battery is on #1.  When I got to the boat Friday
night I noticed a strange smell.  I took the boat out, and when I'm out I
always have the selector on battery 2 saving 1 in case the stereo,
refrigerator, etc. kills the 4D.  After about an hour, it was time to come
in and I tried to start the engine on battery 2.  It wouldn't start from
this battery.

The smell continued through the weekend although the boat was open to air
out.  Sunday I went for a pump out, motoring about 20 minutes to get there.
As always, this was done on battery 2.  After the pump out, we headed back
to the dock, and the boat still smelled.  It was at this point that I found
the boiling battery, switched from battery 2 to battery 1 and grabbed the
fire extinguisher.

After seeing that my charger is a Xantrex True Charge 20, not the OEM, and
noting that the smell was there whether the batteries were charging from the
alternator or the charger, my thought was that the battery had gone bad,
particularly since the cranking battery seems fine.



-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Alan Goodman
Sent: Tuesday, May 15, 2012 7:11 PM
To: c320-list at lists.catalina320.com
Subject: [C320-list] battery / charger issue




Chris  -  I vote for a voltage regulation problem from the alternator,
following up on Jeff's question about your alternator set up.  If you were
motoring and the battery selector switch was set to only one battery (and
not both), and the problem battery is the same as the selector switch ... I
would consider that a compelling indictment
of the alternator.  By chance, did you recently switch selector positions
(battery 1 to battery 2 or vice versa) when the engine was running  ...  if
'yes' that could explain your voltage regulation problem ... IMHO.   Alan
Hull 67 Holland MI

 
> ------------------------------
> 
> Message: 5
> Date: Mon, 14 May 2012 20:41:34 -0400
> From: "Jeff Hare" <Catalina at thehares.com>
> To: <C320-List at Catalina320.com>
> Subject: Re: [C320-list] battery/charger issue
> Message-ID: <000c01cd3233$7b338fb0$719aaf10$@thehares.com>
> Content-Type: text/plain;	charset="iso-8859-1"
> 
> Hey Chris,
> 
> Few questions about your setup might help also:
> 
> - Were you on a doc plugged in when you first noticed the smell but 
> before you went over for a pumpout?
> - Do you have the standard yanmar/hitachi alternator or do you have an 
> upgraded alternator and external regulator?
> - Are your house batteries wired in Parallel or did you have the 
> switch set to just the one that died?
> - Any chance that the air and water temp was warmer where you are than 
> it had been in the previous few weeks?
> 
> In any event, You're most likely the victim of thermal runaway.  The 
> thermal runaway safety zone limits decrease with age and are more 
> likely to suffer from this even if the batteries appear to be in good 
> condition and have good holding capacity.  A warmer than normal 
> battery compartment can allow this to happen sooner, especially since 
> our battery compartments are "insulated" on top.  Chargers that don?t 
> have a battery temp sensor can't know to reduce the float or charge 
> voltage as the battery heats up.  Engine alternator normally produces 
> 13.8v which is higher than a shore power charger's normal float 
> voltage of around 13.2 or so.
> 
> People like to fully blame the ProMariner, but I'd put money down that 
> it's usually some combination of battery age, ambient temp in the 
> battery compartment and the charger's lack of thermal sensor that sets 
> up for this cascade. A problem battery will fry at float voltage in 
> the right ambient conditions regardless of who supplies the float 
> voltage and you're unlikely to have any warning.
> 
> I'm guessing that your battery had a defect that made it susceptible 
> to this earlier in its life than it should have.
> 
> -Jeff
> 
> -----Original Message-----
> From: c320-list-bounces at lists.catalina320.com
> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Karl 
> Mielenhausen
> Sent: Monday, May 14, 2012 7:17 PM
> To: C320-List at catalina320.com
> Subject: Re: [C320-list] battery/charger issue
> 
> You're right Chris... that is a different animal altogether. Most 
> likely a bad cell in the battery. Alternator keeps trying to charge 
> and results in overcharge of good cells. See if one cell still has 
> normal electrolyte level. If so, that is the bad one and it is time 
> for a new battery. You could also use a battery hydrometer to measure 
> the specific gravity in each cell. Differences greater than .02 
> indicate a problem.
> 
> 
> Karl
>