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High Output Alternators

Discussion in 'Commercial Snow Removal' started by GeoffD, Nov 13, 2001.

  1. GeoffD

    GeoffD PlowSite.com Veteran
    Messages: 2,266

    Hey Everyone

    I know some of you guys are useing high out put alternators in your trucks. I am thinking of buying on for an 95 F 350 with only a 90 amp alternator.

    How well do these high out put ones work?

    Do they last?

    Any modifications need?

    And which company do you think is the best to buy from?

  2. SnoJob67

    SnoJob67 Senior Member
    Messages: 384


    Here are my thoughts. I am always for bigger, better, faster, more, etc.

    However, my mind is forever changed about HO alternators. Last season, I bought a 1991 Chevy 1/2 ton that plowed for a city all of its life. A couple of months ago the alternator went out. Guess what? It was an 80 or 85 amp AC Delco alternator that came right from the factory with the truck.

    If it was good enough for the city I bought it from and it lasted them almost 10 years, I'm not going to waste a red cent on a HO alternator. Also, many times you have to make modifications because the HO is larger due to larger coil, etc.

    Ok, I do have two batteries under the hood. As a certified mechanical idiot, I can tell you that I have no idea if this has contributed to the longevity of the factory alternator. :confused:
  3. jimsmowin

    jimsmowin Senior Member
    Messages: 130

    i wait till alt. gets week or goes out. then i'll check for highest factory alt and buy it. they fit right in. i do think a big battery also makes a differance. this has worked for me, been plowing since 1982. wow! thats a long time.
  4. DaveO

    DaveO PlowSite.com Veteran
    from Ma.
    Messages: 299

    HO alternator


    A HD alternator is not a bad idea. IMO the $$ is better spent on a second battery. Electric/hydro setup's nowadays can pull up to ~200amps while moving the blade. This drain is only for a short period, but repeatedly done. If you have a large enough storage capacity(read battery's) they deliver the current. Then while you are pushing/driving they get charged back up.

    All the trucks I have used with dual batteries never had a problem while plowing, voltage gauge barely moves. A truck with a single battery is taxed more, since the alternator cannot supply enough current by itself, thus draining the single battery.

    If a HD alternator is not a ton more $$$, and installs easy, it's a good idea.


    JD PLOWER PlowSite.com Veteran
    Messages: 751

    Geoff is this truck a gasser or oil burner?
  6. GeoffD

    GeoffD PlowSite.com Veteran
    Messages: 2,266

    It is a Gas truck with the 5.8 in it. The trouble is Ford, Napa, or any other auto parts store only list an 90 amp for the truck. The trouble is my poor driver has to run the heat on low, or the truck can't keep up. If he runs the truck on high, and raises the blade, the heater fan wants to cut out on him.

    I am thinking an bigger alternator may fix the problem. My other trucks have the 460s in the old style F 350s, which you could get an 140 amp for.

  7. CT18fireman

    CT18fireman Banned
    Messages: 2,133

    Geoff on my old dump I bought the one for the diesel and fit it to the gas motor. Was not difficult to do. I also added a second battery and this made a great difference.
  8. GeoffD

    GeoffD PlowSite.com Veteran
    Messages: 2,266

    what did you need a different belt? or did it bolt right in? Any other modifications needed? How many amps is the diesel one?


    JD PLOWER PlowSite.com Veteran
    Messages: 751

    Don't know if this will help but my 97 diesel runs the dual amp (55/110) and I still have the same problem your driver experienced with regards to the blower motor and raising the plow.

    SlimjimZ71 posted sometime back about a company that builds or rebuilds all types of alts, I think they are called powermaster? Maybe searching some old alternator threads will come up with something.
  10. GeoffD

    GeoffD PlowSite.com Veteran
    Messages: 2,266

    Well maybe it isn't possible.

    I have thought about the second battery, however no place to put one that I can see.

    It would be nice to be able to crank the heat, or at least run it at medium. With out having the motor cut out, and the lights dim, when you use the plow.

    We clean all the connections 2 times a season so I am sure they are ok.

    Just 90 amps isn't big enough.

    One thing about my truck with dual 115 amp alternators and dual batteries. I can run anything I want, and have no problems.

  11. speedracer241

    speedracer241 Senior Member
    Messages: 325

    dual batteries

    i didn't have room under my hood to add another battery. i bought 1 of those universal battery boxes and a hold down and made a frame out of angle iron to bolt to the floor of my box. i got a roll of heavy gauge welding cable and ends for the battery and eyelets to go to the battery in the stock location. i used a hole saw to cut a hole in the floor large enough to pass the cable through and zip tied the cable to the frame rail. i used a piece of heater hose to protect the cable in any "rub zones". so far has worked pretty slick. cost bout $40 bucks and a couple hours.

    just a thought
    Mark K
  12. SlimJim Z71

    SlimJim Z71 PlowSite.com Addict
    Messages: 1,031

    I bought a 200-amp unit from Powermaster last summer. So far, it has worked excellent. I don't remember having any power issues... and I have a LOT of electronics in my truck aside of the snowplow. Dual electric fans, scanner, radar detector, cell-phone kit, aftermarket radio... not to mention having the heat on, the headlights, the Highlighter, and moving the plow and running the spreader.

    We have a VAT40 (basically a giant fluke meter) at work that has the ability to measure amp draw on a vehicles electrical system. Without the plow & spreader on, I've pulled over 100-amps with different components on... so I can only imagine what the plow & spreader are doing. Like I said, so far so good. Even after 10-hours of plowing, no major signs of voltage loss.

    The only changes I had to make were adding a thicker cable going from the rear post of the alternator to the battery... and I'm thinking of maybe putting a smaller pulley on it just to make the plow move a little quicker at lower RPM's.


  13. GeoffD

    GeoffD PlowSite.com Veteran
    Messages: 2,266

    So the increased apperage was regulated correctly so that electrical system was not damaged.

    I called Powermaster they told me 425.00 for a 200 amp for the truck.

    Then i called another place, out of FL, and they told me 325.00 for a 200 amp one.

  14. John DiMartino

    John DiMartino PlowSite.com Veteran
    Messages: 2,154

    I am almost positvie the 200 amp unit powermaster is selling is the stock unit that comes on many Gm cars,it is the 140csi .140 amps,stock.They rewind it,and add a HD rectifier.This is a 300 dollar unit new,but with a core,can be rebuilt for 75-120 bucks easily.I think the Ford application adapts the GM alternator,Im not positive though.I have one of these alternaotrs on my 89 GMC.it is a powerhouse,totally stock,it bench tested at 150 amps.
  15. CT18fireman

    CT18fireman Banned
    Messages: 2,133

    I had to change the pulley but I am not sure if you have v-belts or a serpentine. The case was a little bigger and I think I had to elongate the adjustment arm. It was a long time ago so I am not sure. It was not that hard of a job though.
  16. john r

    john r Senior Member
    from NJ
    Messages: 239

    If you want replace your current alt. with a new/remaned unit and keep the orig. as a spare. Typically the diodes are what gives out and can be bought for about $7.00 if you search around. I personally have upgraded all the alts. to 130 to 200a. I was toying with the idea of a 300a alt but maybe next year. No prob with what I am using now.
  17. Lou

    Lou Member
    Messages: 74

    Slim Jim has the right idea. The heavier guage wire you can run from the alt to batt is a good start. When I put in a 110amp alt
    I ran heavy guage from negative post to the frame, ditto from the positive post to the selenoid and the starter. The altenator may put it out, but if you don't have the wire to carry it, it's no good.
  18. jason2

    jason2 PlowSite.com Veteran
    Messages: 117

  19. Winterworks

    Winterworks PlowSite.com Veteran
    Messages: 97

    We have had the same problem with our gas Ford's. Any alternator/starter shop can bump up your stock Ford to 130amps. We added a 1050 CCA battery and have had no problems. Cheaper fix than the custom H.O alternators. Also keep in mind that some of those do not charge at idle and low rpm's. I cannot believe Ford installed 70amp alternators in their work line of trucks for that year range.
  20. SlimJim Z71

    SlimJim Z71 PlowSite.com Addict
    Messages: 1,031

    Yeah... but what do you expect, I mean this IS Ford we're talking about.