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gif
01-02-2004, 03:39 PM
I need some technical advice here.

I have collected some used Golf Cart Batteries for an all electric boat being put together.

These batteries are the same size as a fat Car Battery #- but are deep cycle, heavy and are 6 volts #- so two in series gives me the required 12 volts.

At this stage I only have my old 4 amp car charger.


Anyway, I wanted to see if any of these batteries were any good.

First I checked them with a hydrometer and got a mixed result. # I toped up the water and left them for a week. #

Today I got around to setting them up on a wooden base, hooking them up in pairs, and started to charge. # # All of the pairs showed up on the charger as “ full” #- 4 red lights.

But on the hydrometer they are showing up as Red.

Anyway – how can I successfully check if these batterys are worthwhile or they are just ballast?

Thanks!

Gary

basserman
01-02-2004, 05:40 PM
are you sure 4 red light means full?
i know on my charger 4 reds means its flat and they go out as it is getting charged

aido
02-02-2004, 05:01 AM
you need a battery load (capacity) tester.
i once did some time in the batt cave, battery room at work.
we used to hook up a heavy duty resistance and wind it up.
car type batteries could get several hundred amps discharge.
dangerous practice though, imho.

the one auto type guys seem to use looks like a garden fork
with a shunted meter across it. placed across the terminals, it puts
a big load on the batt and the meter reads good/bad.

have a look at super cheap auto or repco might have one.

other than that, charge them all up and take 'em to an auto elec
guy or large battery supplier, they might check them if they think
your going to be replacing them from their shop.

gif
02-02-2004, 05:31 AM
Thanks Guys

Yes Basserman - after I read your post I rushed down to teh garage. yep 1 light is out now - so 1 set is slowly charging. Nothing on the instrction book to say either way!


And thanks for the answer re load testing.

A Big thanks to Luck Phil - who, off line , kndly typed out a bunch of information for me. nice guy!

PS if anyone wants batteries pm me re finding free ( but doubtful) 6v batteries.

Also - like new 12v 100 amp hr tested for $50 ( ex back up suppy - so may have never been used) PM me and I will fwd you the details.


Gary

basserman
02-02-2004, 11:49 AM
no probs gary i had the same thing when i first used my charger used the elctric motor for 2 1/2 days till prop was just turning on full before i put it on charge and all light were on so i rushed back to super cheap and blasted the bloke on the counter before he set me straght ( did i feal like the fool ::))

Big_Kev
02-02-2004, 12:35 PM
Raflmao.