Jump starting M923A2

[juanprado]

Well a small update. Bought a battery charger pulled 2 of the batteries out so far and hooked them to the charger (one at a time). Looks like 1 of the batteries is dead dead. The one showing 3.8v it charges up t to about 6ish then charger shows a fault in the battery. Other one is showing 12.2 and seems OK. I haven't given up completely on the dead one yet but today I'm pulling the last 2 out to charge if at least 1 looks good I'm switching to just using 2 batteries. The batteries are from 04/08 with unknown maintenance so I'm not too surprised.

Quick new question. My truck has 2 small solargizers when going to 2 batteries do I hook 1 to each or only use 1 for the pair? If 1 for the pair where do they connect?

attached is the manual for your reference.

 

[ralph3162]

I have jumped my deuce several times with a 12 volt system and never unhook a single wire. Hook positive to the positive and the hook the negative to the frame or other metal area not to the battery. Start the truck if you have enough amps to turn it. Never hurt the 12 volt vehicle the first couple times I did it, after that I started using a jump box didn't hurt that either. Maybe I have just always been lucky but I have done it at least a half dozen times since I owned the truck. Maybe someone here will have some better info than me I only speak from my own experiences.

 

[Scott88M]

Thanks everyone. Looks like I toasted a battery, oddly enough it was the one initially showing the most voltage. Also due to a small other issue I'm pretty sure that one was at least partially shot before this incident but the truck was able to start despite it. Bought a decent manual charger/jump box for future issues. Switched to 2 batteries and besides accidentally not initially tightening down one wire its been fine and easy to do. And I was even able to reuse the mounting bracket and wires.

 

[KureBeast]

I had to jump my M923A2 the other day. (Mine only has 2 batteries, not 4) I disconnected the short battery cable, the one that is about 4 inches long. I then charged each battery independently. I then load tested them. 1 was good, the other dropped to almost 0V. After making sure the good battery was 100% charged, I reconnected the short cable. Then I hooked my jumper cables from the wife's Yukon (12V) to the "mostly dead" battery. Had her rev the engine to about 2K RPM and then started the M923A2. Started up just fine, disconnected the jumper cables. No sparks, no flames, no nothing. All good.