Jump Start Question

[osteo16]

Quicky question here.. Sooo I have a few accessories on my M998.. 6.5NA with 60amp alt. Im tailgating this weekend and worried my stereo might drag down my batteries a little. I have (2) 12v jump start packs available.. Could I (can I) if needed hook up one jump starter to each battery and jump start my HMMWV effectively.. Or will this cause an issue.. Or could one use (2) 12v batteries from 2 vehicles to jump start?? Questions ... Im contemplating... Thanks Peeps..

Ocho Out !!!

 

[Coug]

24 volt harbor freight jump starter

Check this out. Harbor freight jump starter thinking about hooking it up to a nato slave cable. Much cheaper than the Noico and imop a must have for the hmmwv in 12 volt world. Any potential harm to the electrical system (1165 a1) through the nato plug?

www.steelsoldiers.com

one 12V source per 12V battery.

if jumping from multiple vehicles, be careful that they don't come in contact with each other, as that has the potential to create a 24V circuit through them. Wouldn't be an issue if it's a perfectly balanced 12V per vehicle, but odds are one will see above 12V and the other below 12V, and modern electronics are expensive.

If jumping from a single vehicle, then charge one battery at a time for 5 to 10 minutes (or longer depending on how badly drained your batteries are)

 

[87cr250r]

Yes, I have had to get a jump from a tow truck in my CUCV. The jump packs are not grounded/are the same as isolated ground alternators. Connect each jump pack to a battery or jumper cable one battery and use a jump pack on the second.

 

[Coug]

if your batteries are deeply discharged, your jump packs might not be enough juice to start the truck. Larger batteries will try soaking up a lot of current, so you might either have to let them sit on there for a few minutes (this is assuming something like the 6T series batteries. group 24 are 1/2 to 2/3 the capacity, so while they go dead faster, they also recharge to usable faster).
There are also methods to get around the batteries using jump packs, but I won't recommend them on here as misuse or negligence could cause major issues.

 

[Mainsail]

I had to jump my M1009 back in June. I'd bought two of these when they were on sale, combining a coupon code to get them at a reasonable price.




My worry was when we drive up into the National Forest to roof-top tent camp, and in the morning the battery or batteries are dead- who can you call when there's no cell signal? Then, even after you hike out for help, who is going to jump a 24v vehicle, plus most people won't drive through the overgrown neglected roads to get to the camp site. Anyway, I wanted to be able to self-recover.

My review:

Now that I’ve had a chance to use them, I thought a review is in order.

I woke up the other morning hearing a strange ticking, it was very loud too. I looked out the front window and suddenly realized what it was- it was the Whelen PA/siren clicking through the speakers because the batteries on one of the vehicles was dead, and the relay inside the siren was clicking on and off, and chirping through the speakers.

It wasn’t the one in my Grand Cherokee, and suddenly I remembered I’d left everything on inside the M1009 the day before- two Ericsson Orion radios, GPS, dash-cam, and of course the PA/siren.

Since it was motorcycle weather and I was riding to work, I figured I’d just attack the problem when I got home; a good test to see if I could self-recover if this happened when I was deep in the National Forest camping.

The two jump boxes have been bouncing around in the back of the ’09 since I bought them and charged them up almost six months ago.

I forgot to check voltages, I guess that would have been useful information. The truck was completely dead though, at least the 12v side of things. The volt meter didn’t move at all when I turned the key.

My worry was how much the (mine are 12v) glow plug cycle would drain the jump box, like it could be dead before I even got to the part where I engage the starter…

Strategy…. Hook up one box to the 12v battery and keep one in reserve in case the glow plugs kill the first one, or connect both boxes to both batteries? I chose the latter, and connected both jump boxes to both batteries.

The boxes pulsed- like they sent power, clicked off, then sent power, then clicked off- all the way through the GP cycle (which wasn’t very long being about 68° out). The volt meter jumped each time the boxes clicked off. Not sure what that’s about.

After the wait light went out I turned the key and the truck fired up like I’d put two brand new mil batteries in it. SUCCESS!

I plugged in the boxes to recharge them and they were only down one out of five indicator lights, so I suspect I could have jumped off four or five trucks before really needing to recharge the boxes.

The jump boxes have a volt meter of their own, right at the base of the cables where they plug into the unit. Didn't even notice them until I saw them flash .

So the fear of them being dead is unwarranted- mine were in the truck for six months before I needed/used them and they were still at 100%. The boxes had no problem with the glow plug cycle either.