Quick Battery Question about dead cells

[DumbMF]

Hey Gang,

Newbie here. I just bought a golf cart from some random stranger for a couple hundred. It topped out at maybe 12mph on the flat test drive i took. Got it home and my hilly terrain was a different story. With a full charge I can crawl up my driveway. With less than full it just stops.

So I identified the cart...from the serial number it appears to be a Harley Davidson 1979 MGIV. From the threads I read here I thought I'd start with checking the batteries. Turns out I have 6 Trojan T-105 batteries. Volt test shows over 6 on 5 of them. The Hydro test is consistent on 5 of them. The one other battery has shows 5.6V and the hydro tests for each three cell show 1250, 1100, 1100.

I'm assuming i need to replace the one bad battery. Is that correct?

Also could one bad battery cause some hill climb issues? or do i have some other drive issues??

Thanks!!

MF

[rib33024]

Welcome MF

The one battery is toast/ No good --What year are these batteries ??
And what does over 6 mean 6 what? on the other 5 batteries, and what was the Hydro reading, this info will help--

[DumbMF]

Sorry, I should be more specific since I really don't know what I'm talking about and for that matter...have no idea what I'm doing either...lol.

For battery age, I have no idea. Is there a way for me to tell? The sales pitch from the previous owner went like this..."i have no idea how old they are, that's why Im only charging you a couple hundred for this thing."

So I ran the charger on them the previous night for a few hours. There's a gauge that goes "E F CHG" and has red for E, yellow between, green for F and red again under the chg. The needle shows F, not at the top of the green, just right in the middle of the green under the F.

I took a hydrometer and tested each cell. As mentioned earlier, one was really bad. The others, all three cells were the same for each battery and the numbers were 1265, 1270, 1275, 1275 and 1280.

Then I took a digital voltometer (if that's what you call it) and set the dial to 6V. I plugged in the charger and started charging the cart. Then connected the pos and neg on the meter. The one bad battery had a reading of 5.61. The other five read 6.06, 6.07, 6.08, 6.08 6.09.

So with one hour of experience on this forum, my conclusion...5 decent batteries and one dead battery. If that's correct, can I just buy the one new T-105? Obviously I'd rather not throw down for all 6 if not needed.

Thanks!!

[Ez-Gone]

A good volt reading from a fully charged 6-V battery should be around 6.6-6.8. It looks like all you batteries should be replaced. Changing the one REALLY bad battery will help your cause, but not solve the problem.

As far as aging the batteries, look for a round sticker that has a letter and a number on it. Say it was C6, that battery is a March 06'.
A-Jan. B-Feb. C-Mar. D-Apr..... and so on.
The number is the year.

Good luck with this and from one newbie to another, WELCOME

[e-z-go1988]

The batteries seem decent as far as HG goes but all those voltage readings are way low (50%). If you don't have an auto charger I would plugin the charger again for a few more hours. Flip open the caps to see if you get some boiling, that will give an indication whether you are getting near full charge. Maybe get the indicator needle to the upper part of the green. Negative battery terminal has a date code stamped into it.
Speed up hills with a stock cart?

[scottyb]

Welcome to BGW, DumbMF


What these guys are trying to say is never take a GC battery down below 50% capacity. It reduces their useful life permanently. Check out this chart

[sunking]

You really do not want to put just one battery is series with 5 old ones. If you do that, it will just ruin the new battery in a short period of time. You really need to replace all the batteries.

[scottyb]

If the 5 old batteries are serviceable, and they truly test good, and a good used battery is not to be found (used is preferred)..... then putting a new battery into an old pack may be an alternative to tossing out 5 usable batteries...... what you say is true it will diminish the new battery quickly by over charging it but, sometimes this is still an option. Each user has to decide for themselves how they want to spend their $

[DumbMF]

Thanks for all the replies!!

Turns out my charger is an EZ-Go charger with auto off. So I plugged it in for 3 hours this morning. At the end while it was still charging, i ran the voltometer on all again with the following results: (in V)

6.47
5.97 (this is the one with the bad cells)
6.48
6.44
6.46
6.45

I didn't have time to look for the dates yet, but will report back.

Due to the above V readings and the previously posted decent HG levels, would you guys say I could limp along well enough if I can find a USED T105 to replace the one with bad cells? I mean what rating would be considered serviceable and at what point does one throw in the towel?

Scottyb - how is it that i get a 6.46 reading on my voltometer and your chart tops out at 6.37? is that because I ran the meter while under charge? Should I also run the meter on them when not under charge?

Scottyb "never take a GC battery below 50%" At the risk of proving my user name is fitting...what is GC?

EZ-1988 - "speed up hills in stock cart" I'm not trying to break any land speed records here. At the current climb rate of 3" per second I feel like i should but a brick on the accelerator and get out to help push.

Thanks Guys!!

[DumbMF]

Also...the charger never turned off after the 3 hours. It was still chuggin away. I just didn't have time to wait around any longer. So I"m not sure how much above the 6.4x number i can actually get....