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Reconditioned 8 Volt Trojan Batteries

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zubbly:
Hey all!
Stopped at a golf coarse last week looking for used golf cart batts. They use the Trojan Powerdrive 8 volt units. Six of them in a golf cart for a 48 volt string.
They had some discarded ones with serial Number of I and H of 1996. Took 3 of them.
I recently bought a Vector 2/6/12 amp auto battery charger with a built in desulphator mode. Good time to try it out.
Condition of the batts: cells looked built up with a grey matter which i beleive is the sulphate. Using a good hydrometer, the electrolyte really didn,t make it float at all. Voltage measure out at approx 7.5 volt. Used the golf cart repairmans load tester and showed them to very weak. He said they sat all winter and did not check out.
My Vector charger, because it is automatic, shut down after about 5 minutes mainly because it reads the voltage as too low and not excepting a charge. A message also appeared on the charger to try desulfating. I borrowed a friends big charger and for about 10 minutes, charged on 30 amp then on 60 amp. The electrolyte turned to what appeared to be "mud". I set the desulfator on and let it work over night. The next morning the electrolyte turned "crystal" clear. I did this to all three batts and basically the same thing happened to all of them. (not very encouraging) I again tryed the Vector charger and now ran about an hour before it turned off. Batts after about 2 days of the repeated charging and desulfating started to float the float in the hydrometer. Noticed in one cell of one batt that the float would only float about 1/2 of the other cells. Continued the charging for short periods and desulfating again, with all the batts connected in parallel for about another 4 days.
Its been about a week, i have gotten all the cells to an equal level with the hydrometer and all in the green area (which is good).
Made a load tester today. Had a heating element which i cut into 4 parts and connected all in paralell. Ohm resistance is 1 ohm.
I first connected all the batts in parallel. Voltage measured at 8.8 volt. Used jumper cables to connect to element and a 1 foot piece of #10 wire for a shunt. Current draw was 9.1 amp and batt volt fell to 8.5. I left connected for 10 minutes and batt volt went down to 8.13 volt.
I next connected the batts in series for 24 volt conection. No load volt measured at 24.9 volt. Connected to heating element and volts dropped to 23 volt and current was 24.2 amp. Element did not get red, but definately would have set paper on fire if contacted. I held this test for another 10 minutes. Battery voltage at end of ten minute test was 22.6 volt and current was 26 amp.
After the batts sat disconnected from load for 2 minutes the voltage read 24.8 volt.
Disconnected batts from each other and volts read 8.32,  8.29,  8.27 volt
After 1/2 hour disconnected they read 8.4,  8.36,  8.34
The electrolyte reads right between the line of fair(white) and good (green)
I have never really worked at rejuvinating old batts before and not really sure if i kept the load test on long enough to determine the results (actually, not really sure how to interpret the results at all, LOL )
Opinions would be appreciated.  Basic question is "are they worth using?"
thanks in advance!
zubbly

pyrocasto:
Well I would say they are worth using. Anything you get for free that works decent I would say. :-)
Good find Zubbly and good resurrection. ;)

Norm:
  If they were mine I would keep charging them

a little at time and discharging them just a

little....charge them then discharge them just

a little longer but never more than 10%.

  Okay now you asked if they were worth using ...

if they are even half as 'lively' and the key word was I 'took them' ....not 'bought them'..

  and you said opinions would be appreciated..

so just IMHO !

                    ( :>) Norm.

whatsnext:
Zubbly, Where did you find an 8volt chatger? If you were using a 12volt charger you'd eventually just boil the batteries dry. If you go to Trojan's site you can download a .pdf showing the complete SG vs. charge chart. Also, get rid of your color coded hydrometer and get a real one, they're about $20. It's really hard to get an accurate reading of what your batteries are doing without knowing their temperature and their SG but you seem to have brought yours back to life pretty well and you may have come up with a new method to desulfate batteries.

John.......

zubbly:
Hi Whatsnext!
i am using the 12 volt charger on the 8 volt batts. Probably just raises the current more.(charger has a warranty  :)  )LOL
Who supplies the better hydrometers?
zubbly

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