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Dual batteries or High output alt? Or both?

Discussion in 'Commercial Snow Removal' started by G.M.Landscaping, Nov 23, 2007.

  1. G.M.Landscaping

    G.M.Landscaping Senior Member
    Messages: 362

    Which would you do first? What are the benifits between the two? I'll use my 91 F-250 with a 302 and stock alt and battery for reference. Small lots with lots of quick forward to reverse.
  2. LockedUP

    LockedUP Senior Member
    Messages: 123

    I have a 200 amp alt and 1000cca battery no problems. I really don't need all that but its nice to have.

  3. saabman

    saabman Member
    from Maine
    Messages: 70

    Pump on-rush current is in the neighborhood of 150 AMPS. Add the steady state draw of the vehicle and this would out pace even the biggest alternator. Couple this with the fact that most of the time an alternator is turning slower than the RPM needed for max current and you have a cant do situation. Sure, the more current from the alternator the better but the biggest dual batteries can deliver close to 2000 CCA. When the pump goes on, the batteries have the power and reserve to operate it. Afterwords the alternator can recharge the batteries. The bigger the alternator the faster the recharge.

    Short answer, dual batteries first.
  4. xtreem3d

    xtreem3d PlowSite.com Addict
    Messages: 1,548

    do the high output alternator first.....one good battery should be enough providing your wiring is in good condition
  5. Duncan90si

    Duncan90si Senior Member
    Messages: 602

    I personally like to run dual batteries first. Dual batteries give you that little bit of extra assurance when its 5* out that your truck will start. As long as your stock alternator is in good shape you'll be fine.

    Some guys would rather go with a better alternator due to, the ease of installation (not having to run cables and buy a battery tray) and the additional space needed under the hood for an extra battery.

    Its a matter of personal preferance IMO. Each setup has its pros and cons.

    I see you aren't that far away from me. Best of luck this winter. Let it snow!!!! (I just got back from salting. payup)
  6. G.M.Landscaping

    G.M.Landscaping Senior Member
    Messages: 362

    This makes more sense in my situation. Lots of lifting and adjusting the angle on the plow in the small lots.
  7. xtreem3d

    xtreem3d PlowSite.com Addict
    Messages: 1,548

    i don't think on my gas trucks that the alt can't keep up w/ the electrical demand, in other words they always provide enough juice....i remember plowing years ago when i guess the alt's put out maybe something like 60-80- amps and you would eventually have to turn lights , fans ect off or down to keep juice flowing to plow but i haven't expierienced that in years
  8. murphyslaw

    murphyslaw Senior Member
    Messages: 443

    I did both at the same time. 200amp alternator to recharge the batteries as fast as possible. and two large batteries to handle the load when the pump is turning.

    and I plow in low range so it take only a little speed to make that alternator turn at its rated rpm's and I put on the smallest pully I could get ahold of so it would turn even faster. at idle 760rpm(motor speed) the alternator will put out 84amps(tested) and at 1100rpm(motorspeed) it puts out 203amps(tested).
  9. xtreem3d

    xtreem3d PlowSite.com Addict
    Messages: 1,548

    do you have to worry about "overspinning" the alt when the truck really revs?
  10. G.M.Landscaping

    G.M.Landscaping Senior Member
    Messages: 362

    I'm not even ready for plowing yet:mad: I still have to do all my fall cleanups. Only a couple flurries so far and the leaves aren't all down.
  11. G.M.Landscaping

    G.M.Landscaping Senior Member
    Messages: 362

    Not sure what you mean?
  12. xtreem3d

    xtreem3d PlowSite.com Addict
    Messages: 1,548

  13. murphyslaw

    murphyslaw Senior Member
    Messages: 443

    no I have never had an over speed issue with any alternator exept one that was on my boat and was a special low rpm one.
  14. xtreem3d

    xtreem3d PlowSite.com Addict
    Messages: 1,548

  15. G.M.Landscaping

    G.M.Landscaping Senior Member
    Messages: 362

  16. SnoFarmer

    SnoFarmer PlowSite Fanatic
    from N,E. MN
    Messages: 9,883

    Get two batts first.
    Then when you alt craps out, up grade it then.
  17. 4evergreenlawns

    4evergreenlawns Senior Member
    Messages: 552

    Dual Batt. AND DUAL ALTS. if you are running a HO ALT you WILL BURN it up at highway speeds. Worst thing I did was a spent $$ for a H.O. alt on a PSD. The PSD it make for LOWER RMP with higher torque that is what I paid the extra $5,000.00 when it was built. Now I need to plow in LOW RANGE to pump up the RPM, I could do that with a GASSER.

    Final story Dual Alts, on PSD never again a AMP issue, the 140 AMP single alt with dual batt. works fine on the one truck I have with that config. all the other trucks are DUAL ALTs. DO NOT spend the cash for the H/O alt get something in the 140-150 range so you can run duall batt and drive the truck over 35MPH without costing you $400.00 for a new H/O alt every six months.

    All this is from my personal expereince.

    Ron G.
  18. what size is the stock Alt ??

    If the stock is tested at 90amps and doesnt need replacement,
    check out the new Diehard Platinum with 135min reserve and totally sealed.
    You may be able to get by with one battery-- this is what I am trying this year.
    I did change to a 135amp alternator.

    Your truck may have more options than my 95 Bronco.

    If you could use a new battery-- I would opt for a premium (single) battery.
    [note most advice here seems to be if you have dual batteries--make them
    the same]

    If the alt tests poorly,..change it. Mine was $90 ( less than the Diehard)

    A single good alt and a single good battery works for many.
    Jerre advised that I install a large (#4) cable from the alt to the battery.
    I did that, too.
    He also suggested a large cable to the frame for the ground. Did that too.

    good luck.