Are these batteries any good...?

[Tiwaz]

Lately I have been having a hard time starting the engine, the first turn of the "Run" will produce 1/2 turn of the engine (1/2 a Jiggy).... let it rest for a second or two and at 2nd try one full turn or even two and then nothing, on the third try I get 3 "jiggy Jiggy Jiggy" (Will Smith style) and the engine turns on.
I removed the batteries , put them in parallel and hoked up a 1 Amp trickle charger for about 30 hours, the batteries (after some rest w/o charger connected) read 12.87V with a difference of .1V between the 2, I then hooked them up in series and got 25.75V, put them back on the truck with 4 brand new battery terminals and the results were that this time I still got a struggling starter but it took 2 turns of the "RUN" switch instead of 3.

As a side note I was able to use this box to jump start the engine w/o batteries and i still saw some struggle but it turned on. So now I am confuse and don't know if the problem is in the batteries or someplace else.
My voltmeter inside the car reads 28.3V while traveling and about 28.1V idling and the alternator gauge is pretty much in the center of the green zone (as indicated by the blk line in the picture) slightly below the little white mark on top of the green zone, are these readings pretty normal or on the low side...?

 

[Mogman]

Take the batteries and have them load tested, nothing you have done gives me any confidence you have good batteries, most "jump boxes" are designed to help a vehicle with low batteries not missing batteries so not performing well on the jump box is no surprise,
Nobody on this forum is going to be able to tell you if those batteries are good or not.

 

[MarkM]

Check the batteries independently of each other for voltage. Should be around 12.6 12.7 for a fully charged battery. After it's been sitting for a bit. (Flooded)

 

[MarkM]

Obviously a load test is the only way to properly test a battery but if you have one with noticeably less voltage them you have a battery with issues.

 

[Tiwaz]

Take the batteries and have them load tested, nothing you have done gives me any confidence you have good batteries, most "jump boxes" are designed to help a vehicle with low batteries not missing batteries so not performing well on the jump box is no surprise,
Nobody on this forum is going to be able to tell you if those batteries are good or not.

Got it, in any case the box I used has a "Mode" specifically designed to start a 24V vehicle w/o batteries at all.

If this batteries fail the load test do you have any recommendations for new batteries that are not astronomically expensive....? My consideration is that the OEM batteries need to have a shit load of amps because they will have to serve all kinds of equipment and accessories that the Humvee is designed to support (Radio, Turret, etc.) not having all that gear anymore, do you still need such big batteries...? or can you get away with a pair with less amperage....?

 

[Tiwaz]

Check the batteries independently of each other for voltage. Should be around 12.6 12.7 for a fully charged battery. After it's been sitting for a bit. (Flooded)

I did as I said in post #1 they read 12.87V and the other one 12.75 so about a .1V difference

 

[Greg841]

Got it, in any case the box I used has a "Mode" specifically designed to start a 24V vehicle w/o batteries at all.

If this batteries fail the load test do you have any recommendations for new batteries that are not astronomically expensive....? My consideration is that the OEM batteries need to have a shit load of amps because they will have to serve all kinds of equipment and accessories that the Humvee is designed to support (Radio, Turret, etc.) not having all that gear anymore, do you still need such big batteries...? or can you get away with a pair with less amperage....?

Now I am sure someone here will intervene with some remarks such as "Hey you wanted a Humvee..? pony up, this isn't a Toyata Corolla" please.... spare me...

O'reilly has 6T size batteries for $230 each, not too expensive and the same size as the originals, rated 750cca. You've got to call the store to order them, my store got them in a day. I put them in my truck that was running fine on a pair of much smaller 530cca interstate batteries so you can get away with less. Couldn't find a date on the old ones, but they were definitely older based on the layers of dirt and they didn't have any issues starting this past winter.

 

[Tiwaz]

O'reilly has 6T size batteries for $230 each, not too expensive and the same size as the originals, rated 750cca. You've got to call the store to order them, my store got them in a day. I put them in my truck that was running fine on a pair of much smaller 530cca interstate batteries so you can get away with less. Couldn't find a date on the old ones, but they were definitely older based on the layers of dirt and they didn't have any issues starting this past winter.

Thanks for the tip, the lucky part here is that being in S. Florida I hardly ever have to start below 60 degrees (I know.... I am so lucky)

 

[Tiwaz]

Thanks for the tip, the lucky part here is that being in S. Florida I hardly ever have to start below 60 degrees (I know.... I am so lucky)

O'reilly has 6T size batteries for $230 each, not too expensive and the same size as the originals, rated 750cca. You've got to call the store to order them, my store got them in a day. I put them in my truck that was running fine on a pair of much smaller 530cca interstate batteries so you can get away with less. Couldn't find a date on the old ones, but they were definitely older based on the layers of dirt and they didn't have any issues starting this past winter.

Is this the battery you are referring to...?

https://www.oreillyauto.com/detail/c/fleet-heavy-duty/battery-accessories/batteries---commercial/f78a23ef17b7/super-start-fleet-heavy-duty-battery-group-size-6tl/ssbl/6tl

 

[Greg841]

Is this the battery you are referring to...?

https://www.oreillyauto.com/detail/c/fleet-heavy-duty/battery-accessories/batteries---commercial/f78a23ef17b7/super-start-fleet-heavy-duty-battery-group-size-6tl/ssbl/6tl

That's the one

 

[Tiwaz]

That's the one

Greg, it says that the size is 10.5 X 11.25, while the OEM is 10.5 X 10.0 about 9 and a qtr high, the 11.25 is the size that concerns me.... what do you say...

 

[Greg841]

I didn't measure but they fit perfect in the plastic trays and top hold down. Maybe they're including the handles on the side in that 11.25?

 

[Tiwaz]

I didn't measure but they fit perfect in the plastic trays and top hold down. Maybe they're including the handles on the side in that 11.25?

Then it should really be no problem also considering I do not have the hold down top brackets

 

[Guyfang]

Get the batteries load tested.
Get a battery charger designed to "repair" and charge these types of batteries. HAWKERS are extremely hard to kill. Test first. Then decide if you need to get new ones.

 

[Tiwaz]

I see quite a few people here have switched to LiFePO4 are there advantages (or disadvantages), should I look into that if my batteries turn out to be bad...?

 

[Mrgior31513]

I see quite a few people here have switched to LiFePO4 are there advantages (or disadvantages), should I look into that if my batteries turn out to be bad...?

There are advantages and disadvantages to swapping to lithium cells, one obvious one to keep in mind is that they have different charging requirements, and you should spend some time looking into your system versus straight swapping batteries out, as you may have to modify or change some components for a proper swap. Lithiums usually require a bit higher voltage than their lead acid counter parts, and usually have different stage charging systems.

I keep lead acid in all my autos, as they tend to be better when properly maintained for simple automotive use and it's not worth the hassle. Lead acid vehicle batteries are built for high cranking short use cycles and do great as long as you use battery maintainers/etc.

For anything that has to do with camping/rv/offgrid life I've been swapping my systems to lithium now that those systems have dropped so much in price. I have built battery packs for camping/traveling to take in my vehicles, I don't use the vehicle batteries for power. The safe level of discharge makes the amp/hr per dollar a no brainer on lithium, and the light batteries make portable power significantly lighter with more discharge available. About 6 years ago it wasn't great price wise, but now it's spectacular.

 

[Tiwaz]

do you think I could get away with a pair of these...?
Weize Platinum AGM Battery BCI Group 24F Automotive Battery, 120RC, 710CCA

https://www.amazon.com/dp/B0D6Y7KQYN/?coliid=I231CJ3AXX8AR4&colid=3JOTHV3BC5LRP&ref_=list_c_wl_lv_ov_lig_dp_it&th=1

 

[Coug]

do you think I could get away with a pair of these...?
Weize Platinum AGM Battery BCI Group 24F Automotive Battery, 120RC, 710CCA

https://www.amazon.com/dp/B0D6Y7KQYN/?coliid=I231CJ3AXX8AR4&colid=3JOTHV3BC5LRP&ref_=list_c_wl_lv_ov_lig_dp_it&th=1

No reason why those would not work. I'm running group 24 AGM for almost 5 years now and no issues.
They will bolt down with the original hold down bracket as well with no modifications, but if you get antsy about it you can always cut some lumber to go around them so they can't shift.




Going back to your troubleshooting, you can also do a sort of load test inside the vehicle.

Have the multimeter measuring voltage at the batteries while cranking the engine.

If it drops to below about 22V, then you definitely have a bad battery.

You can also measure each battery while cranking, and they should be about the same amount of voltage drop, but still stay above 11V each.


If it stays above that the whole time, then you may have a bad starter or wiring connection.

 

[juanprado]

My son is a manger at o'reilly's. I have tried their 6tl penn I think made them in my m923 & m998 as the family discount is generous.
They did not hold up like the original wet excides. They also weigh less. I finally moved on .
Group 31 in the m923 and group 24 in the m998.
Note o'reilly has a new supplier. Just installed a group 48 in my tahoe and stunned to see made in Turkey after I was finished....

 

[MarkM]

I went with two Optimas with the adapter trays for a great fit. Almost three years now with no issues. I also run a Pulsetech Solagizer. I park my Hmmwv for the winter and that unit helps keep the batteries up to snuff.

Mark