thanks for all the help from everyone. I have decided to part the lift out and scrap the rest

I do not know if the load test was included in the first test,. they said that if two cells are bad it was not worth fixing. I had two weak cells but one came around and passed good. It sounds like it repairable
I do not have a charger. I have a 24 volt charger but its for a pallet jack type battery and the connectors are the smaller ones. I fouind no stamp on the battery bars but will look again.. I have a slack chain, it is not even on one pulley for the steering. I will have to jack it up and fix that.
serial number is N531563 type F has 729 hours on meter. I will check some more on the numbers and be back. Thanks for the help. I wish I kept my old allis chalmers hahahahahok I did find the date on battery. It was 12-05-01 is that too old?

this battery company should of been able to tell you after the first go around if that battery was any good or not.
if the cells look sulfated or the electrolyte is low or that one cell they said was weak was actually bad the battery will not charge up enough to run the lift. They should of found this out during thier initial testing and known whether or not it would hold up to run a lift. A simple load test on a loadbank tester would of told the story.
A fully charged 24v battery will read in the range of around 26 - 28v depending on the condition of the electrolyte and the cell plates.
Get a standard volt/ohm meter and set it to dc volts and read the voltage from the battery plug and see what your total voltage is. If you have a charger run a charge cycle on it and then let it sit for a few hrs and then recheck the voltage and see if it has increased any. If the battery is any good it will, if it has not changed much then there is more wrong with the battery and needs to be serviced, maybe even reconditioned IF possible. Just FYI, sometimes they aren't worth the reconditioning and it just pays to get another battery.
You can check the date on the battery by pulling off the cell connecting bar covers (if they are still there) and it should be stamped into one of the bars or poles. The serial number and date code should be stamped somewhere on it, usually on one of those areas.

Now as far as the slack light that is probably for the chains, make sure they are tight because if they go slack it will kill the lift operation generally until the condition is corrected. There should be some tension on them if they are adjusted correctly.
You can loosen the chain adjuster on the mast end of the chain and take up the slack in the chain(s) if they are loose so the slack switch will close and re-enable the lift's operation.

Before you do this though check the wiring to the switches or the switches themselves and see if there is any damage. They should be mounted usually at the chain anchor on the platform end of the chain mountings.

can you give serial number off the lift's data plate?

I do not know how long it was out of service. The battery had water in all cells. It is a 24 volt. I do not know what amperage it was charged. Texford in Houston did the charging. It went through a series of charges for one week for an initial test.. They said to try it and see. I do not have the info. I guess I can spend the 325 for the more complete test

How long has the lift been out of service and the battery dead? was there any water in the battery when you got it....what voltage battery is it and how long and at what amperage was it charged to get it to where it is now???