Battery Issues With Marathon

[aauman]

The batteries on my 82 marathon are trojan t-605, are they good batteries? I get 37 volts on the pack and my charger is putting out 42 volts. It does not have any kind of safetys like low voltage or auto cutoff. If you turn it on it puts out 42 volts until the timer shuts it off. I know i have to change one battery but i can not get my cart to do anything more than nudge. Have replaced cables with 2ga welding cable to all batteries, should I change the rest of the cables? There sure are a lot of them on this old cart

[mikesmotortoys]

605's are good batteries. 2 gauge is overkill. How old are the batteries? Why do you say that one needs replaced?

[aauman]

I understand its an overill but the wire was free and the ends only cost me $15. That one battery has a dead cell (rotten egg smell) and only puts out 4 volts. I have no idea how old the batteries are. I did some work for a buddy and got the cart in return. No complaints though, it's done great for three years. I am a refrigeration technician and half of our work is electrical but its ac. I can check and work on just about anything but I just don't know much about how these carts work

[mikesmotortoys]

If you have already owned the cart for three years and never replaced the batteries, then I would plan on replacing all 6, unless you can find a good used one for the bad battery...

[dougmcp]

37v on a pack is about 65% charged. If it's a manual timer, are you sure the charger is running long enough? If it has been run for more than 12 hours and that's all you batteries will come up to then they may be due for replacement. The neg terminal has a manufacturing date code, a letter (month) and a number year), if these are more than 5 years old they may be suspect.
Here's a state of charge chart to help you:

[aauman]

Thanks alot!!! Will check in to further