special charger for AGM batteries?

[Hard Head]

Sorry my shop charger is 140 amp which I ran the batteries on the 50 amps setting for 24 hours periods. The charger never indicated much over 20 amps during this cycle. I did this multiple times and could never get my batteries to test over 60% CCA even when the charger would indicate 100% charge. I could watch the voltage drop from 14 to 10 in less than 5 minutes after they would come off the charger. That is when I went to a better smart desulfating charger. With the price of AGM's I am happy that I have recovered over 14 AGM batteries. Well worth the $600 I have in chargers. I do charge the batteries first with the shop charger for 1 day and then put them on my spare Genius for 1 to 2 weeks depending on how they test.

 

[Suprman]

I am doing some now. I did them one at a time and now have all 4 hooked up. Its a 3 day or so project.

 

[Oxyacetylene]

OK gotcha, so you are just hooking the batteries up with their own chargers as 12v connections for recovery. For maintenance/float, are you using one charger hooked up as 24v, or still using two separate ones as two 12v banks? From what you are saying Hard Head, it sounds like you are using two of them, each connected as 12v.

 

[Suprman]

You need a good 10-20 amps for a 24 hour period to charge each battery. You need to do this individually. Once they all have a decent charge then you can put them into the trucks normal hookup pattern and slow charge them the rest of the way.

 

[Hard Head]

Yes, I have 2 - 2 bank chargers in my truck. That way I have a total of 40 amps max charging capability.

 

[Hard Head]

I have seen it take up to 2 weeks to get a battery back in shape which is pretty good since they are not a dime a dozen!

 

[Oxyacetylene]

Thanks for all the info guys. Sorry to sort of hijack the thread, LOL. Luckily mine came with Interstate AGM's that were only about a year old. Sometime in the near future I hope to permanently mount a charger/maintainer so I can keep them topped off.

 

[Ukraine Train]

So I've had one battery on the Noco charger for about 10 days now and it's not taking a charge. I tried the recovery mode, too. I'm going to try to find a 20 amp charger to blast it with in a last ditch effort. What's a good (cheap) replacement for these, if it doesn't take? Two are still measuring at 12v so I think they're ok but the other two are iffy.

 

[Hard Head]

I bought some Platinum AGM's from Autozone when they were on sale last year. 3 year warranty and they are heavier than an Optima. Just a half inch of so wider for the same CCA. I got with the manager and got him to discount 10 of them for $135 each + core change discount. Turned in a couple old lead acid batteries. Seems just about every gensets I get from GL now is missing batteries! I did purchase some yellow top's D34/78's for $179 last year for several gensets (customer request). Someone on SS has to know where some are at a good price!

 

[cranetruck]

Lead acid batteries should always be fully charged, especially in below freezing weather and maintainers are great for this.

If they sit for any length of time at a lower voltage, they will begin to sulfate and never regain full capacity. A good way to test the battery is to check the specific gravity of each individual cell (not possible if cells are sealed, of course), voltage alone can be misleading as far as indicating "fully charged" condition.

 

[Ukraine Train]

Yeah it was my fault for letting it sit. I'm also not getting 28v from my regulator so I think it was never really topping off the batteries anyway. I'm going to tap an extension cord into a light on the front of my shop so I can keep a charger on it all the time when parked.

 

[gottaluvit]

I used a 40 year old 6 amp 12v charger on the two batteries I had that had about 3v in them. At first I gave up on them and considered them dead, just using two in my truck. They took no charge in 24 hours. Then one day (months later) I decided to throw the charger on one for "days" to see what happens. On day two I had nearly 12v showing so I gave it an extra for good measure. Did the same for the other "dead" battery and it recovered as well. Now I have four healthy batteries cranking over the 8.3 like it's a four cylinder VW!

 

[Ukraine Train]

Home Depot has a 40 amp charger... gonna just pick one of those up and give it a shot. Gotta get this fixed, I miss driving my truck!

 

[gottaluvit]

I hope that works. A lot of "modern" chargers are digitally controlled and are a fail in many aspects. I had a friend give me a battery out of a burnt up battery booster because he said his charger said it was not able to take a charge. One day on my old analog unit brought it up to 12.4v and it is now on a trail camera. I would keep an eye out for old units in yard sales this summer.

 

[UNIMOG-GUY]

I bought some Platinum AGM's from Autozone when they were on sale last year. 3 year warranty and they are heavier than an Optima. Just a half inch of so wider for the same CCA. I got with the manager and got him to discount 10 of them for $135 each + core change discount. Turned in a couple old lead acid batteries. Seems just about every gensets I get from GL now is missing batteries! I did purchase some yellow top's D34/78's for $179 last year for several gensets (customer request). Someone on SS has to know where some are at a good price!

$179 is a great price for Yellow tops D34/78. Best I've been able to do (with a core and a coupon code) with Advance Auto is $186. The $186 price is all day everyday tho.

 

[Suprman]

Plastic spacer plates are available so the red tops can sit centered in the 6tl square space.

 

[Overdrive]

I am doing some now. I did them one at a time and now have all 4 hooked up. Its a 3 day or so project.

View attachment 605560

That's the same charger I used on my 4 LMTV batteries two of which were dry when I jump started it off the transport truck. Did repair mode on all of them and I leave the charger always connected when parked. Batteries still going strong although I want to switch to AGM when I have a spare $1600. Don't like cleaning up battery acid with baking soda.

Just an FYI you can jump start an LMTV from a 12v car if you have a multimeter and brass... um you know. In my recovery post trying to get the truck off a flatbed. Be darn sure you know what your doing. Jumper cables NOT the NATO connector which is 24v.

http://www.steelsoldiers.com/showth...ay-needs-a-jump-assistance-please!&highlight=

It is worth the time to go thru the battery bank and put the multimeter on each battery and understanding how the are connected. Since the truck is a multi-volt system it's not just the generator putting out both 12v and 24 v. Check it out and you will see what I am talking about.

 

[Overdrive]

Do you have the Hawkers? Mine look like they're sealed up pretty well; how'd you get water in?

Sorry I didn't see your question. First attempt I used a small water bottle and a woman's compact mirror. Hilarious but it worked. Stupid thing is now in the required LMTV toolbox. I wound up pulling all 4 batteries to get all the acid and corrosion taken care of. After the ordeal of course, I bought a battery bulb filler thing.

It is a sight to behold seeing a person check and fill batteries on an LMTV with a 3 cell Maglight, water bottle, and a makeup compact. I should make a battery maintenance kit

I have the Exide 6TL batteries

 

[Ukraine Train]

Sorry I didn't see your question. First attempt I used a small water bottle and a woman's compact mirror. Hilarious but it worked. Stupid thing is now in the required LMTV toolbox. I wound up pulling all 4 batteries to get all the acid and corrosion taken care of. After the ordeal of course, I bought a battery bulb filler thing.

It is a sight to behold seeing a person check and fill batteries on an LMTV with a 3 cell Maglight, water bottle, and a makeup compact. I should make a battery maintenance kit

I have the Exide 6TL batteries

So did you pry out the six little plugs? Or do your batteries look different from mine? I've now tried three different chargers on mine and none of them work. The last one is a 40A charger but it just automatically goes into float mode when I hook them up. Anything I can do to try to salvage them? Maybe they're just low on water too?
This is what mine look like:

 

[Kambaku]

How old are your batteries, original equipment? Photo looks new, but I assume it's a pasted in web-shot. A new Hawker has an 18 month warranty and reports of a long shelf/use life.

Hawker's website lists a lot of information for the use and care of the Armasafe Plus Battery http://www.hawkeraplus.com/why_armasafe.htm