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Dueling Batteries

Discussion in 'Commercial Snow Removal' started by GeeMC, Mar 10, 2003.

  1. GeeMC

    GeeMC Member
    Messages: 51

    Hi Everyone :waving:

    During the 24” storm we had around here a couple of weeks ago, the battery light was coming on when you held down the fish stick button after the blade was stopped in the raised position. The truck had been running for about 10 hours straight when this started to occur. The light didn’t stay on, it just flashed momentarily. This led me to believe that the battery may be getting week. It is a 700-cca-factory battery rated for 6 years and is going on its fifth year at this point. I load tested it and it is running at peak performance, but I didn’t like the dim lights and the slow performance. The voltmeter was constantly on a 14.8 charge. I know this is normal under these conditions when you have the plow, heater, wipers, radio, and all the other electrical equipment going, but I still got an uneasy feeling that all this loading is putting to much demand on the system, so my solution was to put in a second battery.

    I got a new 1000cca battery from NAPA and made up some cables and hooked it all up. The truck had a second battery box, so location was not a problem luckily. (Although I had to move the plow isolation module because that is where we originally put it.) Anyway, I ran the second battery in series and was considering installing an isolation diode to separate the two and dedicate one for the plow and the other for the truck. The way it is set up now seems to be working fine, without any lights dimming or lagging recovery times, but I was wondering what the advantage would be to change the system to independent batteries.

    Below is a pic of the setup.

    Thanks for your input,


    2 bat.jpg
  2. wyldman

    wyldman Member
    Messages: 3,265

    I sure hope you didn't run the batteries in series,the truck won't like that at all.

    The batteries should be in parallel,or positive to positive,and negative to negative.

    If the original battery is 5 years old,I would replace it too.Pairing a new battery with an old one will damage the new one as the old one fails.

    Run the batteries together,do not isolate them.You need all the reserve possible.The two batteries will help the problem from re-occuring,but only for a bit longer.Once the second battery gets run down too,you will be in the same boat.

    The only advantage to isolating the batteries,is if the plow battery were to get run down,it wouldn't kill the truck battery,and the truck will stay running.Not much good though if you can't use the plow.You would also need a proper isolator and wiring,which just adds $$$,and more things to go wrong.

    You should look at maybe upgrading the alternator to help charge those batteries better.

    Might want to check over the pump and motor too.A bad motor will draw excessive amperage.

    After a long plow session,charge the battieries back up fully with a battery charger,not the truck.Charging them with the truck will only lead to alternator failure.

    One last trick is too modify your plowing style.Operate the plow as little as possible.Don't lift it all the way to the top,or hold it there.Let the snow lift it as you come into a pile,lift it for a sec,just before you hit the pile,and it will ride up into the pile on it's own.Then just hit the lift for a sec,and the arm will come right up with no weight on it.Don't angle the blade with snow on it unless absolutly neccesary.
  3. Big Nate's Plowing

    Big Nate's Plowing PlowSite.com Addict
    Messages: 1,266

    good luck with that exide battery, my last one only lived for 4 weeks, now I got a orbital xlr exide and it is already giving me slow cranks in the morning

  4. GeeMC

    GeeMC Member
    Messages: 51

    Ooops! Yes I did run them parallel. I just missed typed it. Thanks for pointing it out Chris.

    How will the older battery damage the new one? The only thing I can think of is that the performance would only be as good as the weakest battery. Upgrading the alternator is a good idea. The factory one is in there and it is only 100 amps. The pump is new along with the plow. I doubt it is the motor. Something I didn’t mention earlier is that we adjusted the quill to up the plow speed and the battery light stopped coming on. So I know that helped too.

    We operate the plowing style pretty much what you are describing also.


  5. GeeMC

    GeeMC Member
    Messages: 51

    Just 4 weeks Nate!! Boy I hope it doesn’t run in the family. There is an unconditional 2 year full replacement warranty on it and pro rated for 5 years. If it does go prematurely, what brand do you recommend?

  6. wyldman

    wyldman Member
    Messages: 3,265

    I'm not sure of the exact science as to why a new battery will be taken out by the old one,but it does happen.We see it quite a bit as all of our trucks run dual batteries,and we see a lot of diesels in the shop with dual batts as well.Never had any luck replacing just one.

    I think it due to the fact as the older battery gets sulphated,it becomes harder to charge,which makes the voltage regulator charge it harder.I think this overcharges the new battery,and damages it.Some older batteries are the opposite,and will not take a charge,or show fully charged,when they are not.This causes the second battery to not recieve enough of a charge,and it goes dead quickly.This causes deep cycling,which can also damage a standard automotive battery.

    Either way,you should normally do both together,with the same size,style etc

    I haven't had good luck with Exide either.We used to be an Exide dealer way way back,just got tired of all the failures.I have since switched to selling Interstate and only one failure due to a battrey getting upside down in the back of a truck,and they warrantied it.Interstate would be my recommendation.
  7. RAZOR

    RAZOR Senior Member
    Messages: 343

    Would there be any benefit to switching to a deep cycle type battery for a plowtruck?

  8. wyldman

    wyldman Member
    Messages: 3,265

    Deep cycle batteries are meant to be run almost completly dead,and then recharged completly with a special charger.

    Most plow trucks should not be running the batteries completly dead all the time,as it doesn't make sense.If you have a truck that just barely makes it through the storm,and ends up with a dead battery,then a deep cycle would last longer with all the recharging,but why would you want to do that.

    Deep cycle batteries will also confuse most automotive voltage regulators,so they won't charge properly,and can even damage the battery or alternator.

    A good setup,with dual batteries (reserve capacity is what you want),and a good strong alternator that can handle the charging duties,and it will be fine,no need for deep cycle batteries.
  9. GeeMC

    GeeMC Member
    Messages: 51

    Thanks for the input Chris, much appreciated. What size alternator do you recommend?

  10. ZMC

    ZMC Junior Member
    Messages: 13

    I use optima batteries on my dual set up, a custom 125 amp alternator and heavy duty battery cables.

    I have had no problems with power at all.

  11. porkhead1

    porkhead1 Member
    Messages: 70

    Deep-cycle batteries are for low, slow amperage draws like an electric trolling motor or lights in a camper/trailer.........
    Every time you operate your plow, you're drawing about the same amps as starting your truck.....about 175amps +........
    So, install 2 new batteries & check with a local alt. shop for a hi-amp output alt. for your truck. Or, I'm sure that there will be enough responces to this post that you should get some web sites. Leece-Neville makes some good alt., but they're $$$$$$$$ like 100 amps+ at idle.......

    Good luck.......
  12. GeeMC

    GeeMC Member
    Messages: 51

    I did look at the alternators at Leece-Neville. Wow...are they pricey. The truck has a 100 amp alternator now, How much difference is a 125 amp unit going to give me? I know, I know 25 amps...ha ha! But in terms of price to performance, is 25 amps going to make a difference? Is 125 amps enough or should there be more? After I replace the weak battery with an identical new one, will the factory 100 amp alternator suffice?


  13. CT18fireman

    CT18fireman Banned
    Messages: 2,133

    If you talk to Optima they recommend their deep cycle batteries (yellow top) batteries for plowing. I run the yellows in my trucks and never have a problem. All run the stock alternators. Never had a truck die or not restart.
  14. wyldman

    wyldman Member
    Messages: 3,265

    The Leece-Neville alternators can be pricey,but they have a lot of common ones in the $130.00-200.00 range,and a lot are brand new,not rebuilt.They may not be a direct bolt on though.

    The 25 amp difference may not make enough of a difference to make it worthwhile.Especially if it's the same frame size alternator.The problem with small frame alternators is they require a lot of RPM to make the amperage,and that when they get hot they don't put out much amperage.They also get very hot trying to keep up.

    Take yours off and have it bench tested,when hot and under max load,to see what it puts out.You be suprised how little it is sometimes.I'd say you'll see only 50 amps max,when really hot.Test a 125 amp unit too and see.A bigger alt will put out near the rated amperage even when hot.My Leece-Neville put out almost 200 amps on the test bench,not bad from a 140 amp rated alternator.

    I'd replace the original battery,with the biggest you can get to match the other new one,and try it.You can also add another 8 gauge charge wire from the alt to battery to help it charge easier.It should be OK.If it still runs down on you then you may have to look at replacing the alt.
    Last edited: Mar 10, 2003
  15. wyldman

    wyldman Member
    Messages: 3,265

    The Optima Yellow top deep cycles do not have as strict charging requirements and have an internal resistance close to a standard battery,so they will work good in an automotive application if required.They just don't have the reserve capacity that some of the larger lead-acid batteries do.I think they may have a larger Group 31 size now that may be better in that regard.
  16. fastjohnny

    fastjohnny Senior Member
    Messages: 654

    Has anyone had any experience with a company called alterstart?

    They sell a bunch on ebay, and advertise a 180 amp direct fit alternator for the chevy/gmc. Price was $129, and is a new unit.

    One of our plow trucks it just like GeeMC's. Dual batteries, but only the 100 amp alternator. I had to jump him 2x the last time out. He has mismatched batteries. One is an optima, and the other is I dont know.

    My truck has the 124 A alternator, and does fine.

    Chris, have you done any mods to fit the Leece-Neville alternator into the chevy trucks?


  17. wyldman

    wyldman Member
    Messages: 3,265

    I have done a few,but mostly the older ones.The alternators are really deep,so when mounted to a typical pickup truck engine,they stick out way to far to get the belts to even come close to lining up.

    We mounted the alternator to the frame and just ran two v-belts across to it.We used a heat shield to protect it from the manifold heat,and used solid motor mounts,so it wouldn't chuck the belt if the engine moves around on the rubber mounts.

    Here are a few pics to illustrate the difference in size.
  18. wyldman

    wyldman Member
    Messages: 3,265

    From left to right.The Leece-Neville like I use on my truck,a stock older chevy alt,a newer style chevy truck alt.

  19. wyldman

    wyldman Member
    Messages: 3,265

    One more.

  20. wyldman

    wyldman Member
    Messages: 3,265

    I just checked out the alterstart website.Doesn't look like bad stuff.I'd be concerned how long a high output unit in such a small case would last,but for 130.00 you can't go wrong,maybe worth a try.Here is a link to what I found.

    180 amp GM alt