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4 battery coversion to 2 batteries

motorolanut

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Glenwood WV
Hi All,
Pardon the silly question but I searched the threads and only got MORE confused..LOL and :deadhorse:


I am changing my M813A1 from 4 6TL batteries down to 2 group 31 size batteries.

Anyone have a picture or wiring diagram of the battery cables go for just 2
12 volt batteries?

Thanks!!
 

dmetalmiki

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battery wiring

it;s simple really..IF THE VEHICLE is 24 VOLT then there are (only) TWO cables main. ONE goes to the starter motor ONE goes TO EARTH (chassis) ((bolt)). ANY other cabling is for jointing the (4) batteries in parralel. with ALL batteries(and jump cables) removed you (now) have TWO MAIN cables. so, for TWO 12 VOLT batts.:: ground lead (bolt) to negative on FIRST battery, THEN link the POSS on the first battery to NEG. on the second battery, then POSATIVE from the 2nd battery to MAIN starter cable. Two times 12volt = 24 volt.
 

pctrans

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BUT......being you are in a cold weather climate, you might want to consider using (4) Class 31's; or 2 class 31's and 2 #7534's from Napa. Fills the batt box nicely. And the 7534's have a good crank output. Down here in Florida, we can get away with just 2 batteries, even in the winter.
Just my 2 cents.
 

mckeeranger

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It would be the same as a deuce.

We did the same thing to our XM817, and have had trouble starting it when it's below 15 degrees. Other than then, it's been just fine.

I don't have a pic handy, but if you still would like to see one in the morning, I'll go out and take it.
 

cranetruck

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You want pictures? Here you go.
While you are at it, observe the rules shown in image #3 below. For max reliability, minimize the number of cable connections at batteries.
 

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motorolanut

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Location
Glenwood WV
Ah Ha, Much appreciated to ALL!:D

I bought two heavy duty deep cycle marine sears platinum (odessey's) AGM (Absorbed Glass Mat) Group 31's 1150 CCA's each
and it starts beautifully. Much better than it ever did will the 6TL's..

Now I just need to install my Guest Charge Pro and I will be all set.

Once again thanks to all...This is just another reason why SS is the best forum for the OD addict...
 

cranetruck

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Excellent choice IMHO.
The AGM types will charge faster than the regular lead acids and the extra terminals are great for a clean installation.
"Marine" grade for better deep cycle operation in addition to the starting. One day I will have the money for a couple of those too. :)

About your maintainer, you may want to consider switching it in and out so that it isn't always hooked up to the battery terminals. I have blown at least one of the Chargetek types from transients during starting.
 

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motorolanut

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Location
Glenwood WV
Thanks Cranetruck, Once I wire up the maintainer, I will just pull the fuses from the + positive charge sides of the maintainer
before I attemp a start. The maintainer says its compatible will AGM type batteries so I don't see any other issues. I just have to figure out a way to fasten down the Group 31's in my battery boxes now. LOL

Those batteries were expensive BUT I have been saving up my sears gift cards over the past two years, So the pain was only a little at the cash register.
I considered new 6TL's but could not find any blems in noth central WV, Then I priced 8D's as well.
All told the AGM's were not that far off in price from the others. I have had good luck with AGM types before in other vehicles. They have a good warranty and require a **** of a lot less maintenance than regular acid batteries.
 

Monty

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Location
Raymond Wisconsin
I purchased two group 31's, for my m818 and didn't have a problem starting the truck in late January last year when I brought it home.

I followed the cold weather starting procedure on the dash and after about four turns she fired right up. I think if I would have had to repeat the procedure more than a couple of times it may have been an issue.

Just my .02.
 

motorolanut

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10-4 on the Group 31's....It all boils down to CCA's when you buy batteries and keeping them charged to the 98 to 100% level.

BTW How did you fasten your group 31's down in your battery box Monty?
 

pctrans

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Winter in FL......HAHAHAHAHAHAHAHAHAHAHAHAHAHA

That's funny.....I don't care who you are.roflrofl
WM - It was cold as ell down here this past winter. We lost a lot of palm trees. Second coldest winter on record in the last 100 years. Now it's been hotter than I can remember.
 

Monty

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10-4 on the Group 31's....It all boils down to CCA's when you buy batteries and keeping them charged to the 98 to 100% level.

BTW How did you fasten your group 31's down in your battery box Monty?
I blocked them in with wood, I also wraped the positive terminals with rubber just in case.
 

groundog

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:driver:I installed two group 49 batteries from wally world---930 cranking amps and a 3 year free re-placement---here in Arizona we dont have to worry about cold weather---seems to crank better then the 4 6tl batteries----they also set low in the battery box
 

mckeeranger

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Location
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I blocked them in with wood, I also wraped the positive terminals with rubber just in case.
We did the same. We also put them in one box.

I'm not sure what to do with the other box, I might make a cover for it, clean out any acid residue, and store the jack in it. It's a shame to waste the space.
 
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