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Tuuk Tuuk is offline
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First recorded activity by BoatBanter: Jun 2009
Posts: 4
Default Boat battery question???

Hi Larry

Thanks for the reply and expertise,,

I do not have a dvm or specific gravitity measurer.

So I should shut it off now because it is lightly bubbling on the 2am charge
because it has not reached the capacity point where the automatic shut off
should have shut off. I tried it on an old 12v deep cycle and it did charge
it quickly (maybe an hour) and green light came on. But these two new ones
which are larger in size and weight are not shutting off the automatic
charger yet. I am a bit reluctant to charge it in the 10amp. The folks at
the C.T. told me to bring in the batteries and they will put a 30amp on them
and have them topped up in minutes but I did some reading and that can't be
too good for the deepcycle batteries.

Without the dvm or hydrometer I cannot really do much as I will need to know
the condition of battery and maximum charge coming off that charger.

I will look for those tools,

thanks






"Larry" wrote in message
...
" Tuuk" wrote in
:

I have had the 2amp charger on one of the batteries for about 6 hours
or 8 hours and little bubbling going on I can hear and the charger
still is not changing from red light (charging) to green light
(charged).

Should I keep it on the 2am for longer? Batteries are only 1 week old
from Canadian Tire and charger is also new.

Is the bubbling a concern? It is not boiling over, but listening very
close you can hear the bubbling.



Got a digital voltmeter? They're only $4 at the Chinese cheap tool
stores and are very accurate. With the charger running, you should not
see over 14.8VDC at the battery terminals. You must be awful close if
it's bubbling loud enough to hear. Don't leave it on bubbling so you
can hear... Modern batteries not being overcharged use almost no water
over long periods of time. If you have to refill the battery very
often, you're overcharging it.

While you're foraging for a DVM, buy a temperature compensated
hydrometer, not the cheap crap with the floating colored balls, one that
has a real thermometer buried in a rubber housing from the NAPA store or
where mechanics buy auto parts. That's the ONLY way to tell what
condition your battery cells are in. When it's charged, the specific
gravity, compensated for temperature of the electrolyte which is the
only way to get an accurate reading, should be 1.270 sp gr. All the
cells should be within .005 sp gr of each other. If you find a low
cell, way off from the others...bad battery needs replacment under
warranty. It does happen.

Remember, batteries are only refilled with PURE DISTILLED WATER, not
spring water, city water or that crap in the hose on the dock....(sigh)
Distilled water is available at grocery stores to put in clothes irons.
Make SURE it says STEAM DISTILLED, not just demineralized by pouring it
through a cheap filter gadget.



--
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Larry

If a man goes way out into the woods all alone and says something,
is it still wrong, even though no woman hears him?