Need Advise! JLG 2658e3

[Josh F.]

New to the Forum. Hoping to get some answers here. Just bought an older JLG scissor lift 2658e3. Previous owner had just put in 4 new interstate batteries in it. He brought it on a trailer to my warehouse dropped it off and we hooked it up to a charger right away and the charger started charger it seemed as normal. He then left and I was monkeying around the shop for awhile and the battery % indicator stated that it was at 80% capacity, so I decided to just keep it plugged in and I left. That was almost three days ago. I went back to the shop this afternoon and I walked in and the battery indicated was still at 80% and the charger was still charging. Now, should I assume that the charger never shut off? Not sure how long it should take the new batteries to charge, I know it shouldn't take more than several hours. I took a multimeter to each battery right after I took it off the charger when it was still indicating 80% full and each battery read 6.9 volts. I drove it around a little bit and then remeasured the batteries and they were are 6.5 volts. Did a couple more things on the lift and before I left a couple hours later a remeasured one more time and they were at 6.3 volts. I should also mention that I had my wife go on the lift and run it while I measured the voltage and the batteries were measuring 5.7 volts while she was raising the platform.

So, long story longer, should I be looking at the charger or something else. I would have assumed that the batteries would have stayed topped off after being on the charger for 3 days and stayed at 100%. I didn't plug the lift back in before I left in fear that the charger is not working correctly and it wouldn't shut off after completing the charge and some how ruin the brand new batteries. I am not too savoy on these machines so I need some expert advice on where I should start looking for problems, if there are any. Thanks everyone.

 

[Malingos]

Hello Josh, very good info on the issues and good that you checked voltage at several times. From what I know ,is that the chargers are commun and do go bad. You could charge batteries individually and then hook all up and see if they stay charged or they go back down, but most likely it'll be the charger.

 

[Txhayseed]

First thing is get a hydrometer. You need to know the specific gravity of each cell to know the state of charge on deep cycle flooded batteries. A voltage meter is not going to give you the information you need to start. Once you have established the state of charge you can actually tell if the charger did its job. 6.37 would be a fully charged battery. Do you know what charge you have ? Delta q ? Eagle ? Is a rectangle unit with a yellow top ? The way the chargers work and you can test with your meter for this. They come on and do a diagnostic check for pack voltage. It then enters its first charge stage. With your meter on the main positive and main negative you can see the voltage start to slowly rise. The charger will then go to its second stage and crank up the output to about 28- 29 volts and hammer down on the battery pack to charge. Then it will go into a float charge for the last stage to finish and maintain the charge. The chargers can be very picky and are designed to cut out and shut off if they see a voltage spike, drop, amp draw out of range etc to keep from blowing up a battery or burning your lift down. Once you check your specific gravity and you know what you true state of charge is run the unit and draw the batteries down. It seems counterintuitive but new batteries will take a good 15+ charge cycles to really start taking a full charge and provide the max run time. My guess is everything is working but 80% is just what your going to see since batteries are newer.