M211 Batteries...what was there when the military was using them and what will work?

[sanmigmike]

I was looking at M211 and it doesn't start... Hasn't been run in a year or so. So I am guessing that the batteries are shot. I stupidly didn't write down what batteries were there and I don't have a manual yet (not sure that would give me the info to get a current production battery anyway) so I am looking for suggestions on what battery will work in a M211. If I had been thinking I'd have measured the battery mounts and just tried to find the biggest battery that would fit in the space. Supposedly it was running great when parked... Thanks.

What parts am I going to have a problem finding? I understand rebuild kits are available for the transmission but there might be bit of shortage of the basic tranny if you damage the case?

Any thoughts on bringing a M211 back to life that hasn't been run or driven in year?

 

[Stan Leschert]

If you have problems, send up a blank usb memory stick, and I'll send down the ones that I have. Jtonka (vendor on this site ... search!) has most of them online.

As for batteries, 6TL s work fine. You don't need 6UTL as, that is rated for under water, and if you try to take an M211 that deep, you have other problems!

 

[M543A2]

I used two group 31 commercial batteries in mine for years, worked fine in winter.
Regards Marti

 

[M543A2]

Please call pm or call me to discuss these trucks if you wish. I have owned one for years and used it for heavy work with good success. I can give you maintenance tips.
Regards Martin

 

[hendersond]

Please everyone, don't hate me for this, but....

I have one truck with new group 24 top post batteries. ($74.00 each)
The other truck has one side post battery out of a plymouth neon and a deep cycle trolling motor battery. (used and free) Both trucks started when it was below zero many times this winter.

I can't spend $180 for a battery, I spent my money on good brakes.

 

[sanmigmike]

I'll agree that brakes are more important if the truck is moving...

Please everyone, don't hate me for this, but....

I have one truck with new group 24 top post batteries. ($74.00 each)
The other truck has one side post battery out of a plymouth neon and a deep cycle trolling motor battery. (used and free) Both trucks started when it was below zero many times this winter.

I can't spend $180 for a battery, I spent my money on good brakes.

I am a bit surprised that the unmatched batteries work but I don't know a lot about batteries. Brakes are something I don't cut corners with so I agree with you there!

 

[hendersond]

Un-matched batteries...

We are running 24 volts, that is 2-12 volt batteries in SERIES. In a 12 volt system with multiple batteries, they are in PARALLEL. There is the difference. In series all you need is 2.something volts per cell, if one cell, or even 6 cells are a little weak they don't have much affect on the stronger cells. Basically you are just adding the voltage of all the cells. Your batteries will be between 12 and 13.6 volts.

When you run batteries in parallell, you have a different story. You have 6 cells in series and another 6 cells in series. but 2 batteries in parallel. If you have one weak battery and one strong battery, the weak one will pull the strong one down. In other words, the strong one will attempt to pull the weak one up! Even if they have different CCA or charge levels they will even out the amperage they hold. If they are good batteries, one with 100% charge and the other with 50%, you will have 2 batteries with 75% charge. That is assuming they are identical age, size, cca and so on. If one is bad, eventually you will have 2 equal, but dead batteries.

Think about jump starting a car. You are hooking the cables in parallell, + to + and - to -. You have one dead battery and one charged battery. When you hook up the jumper cables and you get a spark. That is the current running from the charged battery into the dead battery. if you don't have your car running you will have 2 cars that won't start!

Over the road trucks usually have a lot of batteries in parallel. They should be identical and replaced in sets for the above reasons.

Our simple 24v trucks, well, they too should be replaced in sets, but they don't have to. It would be best practice, not an absolute. If you are 6 years into a 7 year battery and 1 year into the other 7 year battery, you deserve a battery problem in 1 year and again in 6 years!

I'm giving myself a headache.

 

[hendersond]

I have one peice of advice, Get it running, check it for safety, check brakes and take it for a ride and see how it shifts. Brakes and shifting are the two big money pits that grind these trucks to a halt. Start at the right front corner and inspect every piece on the truck while working your way around, under, inside and on top. Get a good friend to make a list while you inspect.

Divide your list into two. Need and Want. What needs to be fixed and what you want to modify. Then prioritize your each list and put a price to each. Total each list individually and start budgeting. Work on both lists, but work smart. Start on the high priority needs and keep your eyes open for the wants while you go.

And never, never, never take more shi..stuff off your truck than you can put back on in 1 weekend. You may never drive it again!

 

[cmpman]

My experience with the batteries in the 24volt systems are that they must be of similar size and similar condition. Otherwise, during starting, the weaker battery will discharge quicker, and during charging, the battery in good shape will charge first while the weak battery will resist the charge. For that matter, it doesn't have to be the whole battery, but since each cell is in effect a battery, one bad cell will eventually bugger up the whole system.

I have also seen one of the two batteries reverse it's polarities when only one new battery is added to a bad battery,,,,I can't explain that one.

While the 6TLs are ideal, there is nothing wrong with even using a pair of standard group 27 batteries. The Canadian army actually had a modification to allow for the installation of the commercial batteries for when the military batteries were not available.

I will agree with hendersond on the priorities: no point starting a truck if it won't stop. Brakes (and steering) before all else.

 

[hendersond]

I have also seen one of the two batteries reverse it's polarities when only one new battery is added to a bad battery,,,,I can't explain that one.

You have to completely discharge the battery, then hook it up backwards and recharge it backwards. I suppose if you hooked one up backwards it would discharge the weaker one, them jump it with 24v or recharge it backwards. Either way it is result of human error.

I like the group 27 idea. They are reasonable priced and readily available.

 

[nattieleather]

Find two Ultimas that fit and put them in. But the correct answer was the 6TLs where the "factory" batteries. I've seen some M211 and M132s running "jeep" batteries with two 2HNs which is why I said Ultimas. I have seen national guard units that have put ultimas in place of GI batteries as replacements.