Wrong alternator on 71 351 4V

Discussion in 'General Ranchero Help' started by F-6Garagerat, Nov 27, 2014.

  1. F-6Garagerat

    F-6Garagerat In Second Gear

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    So we have the a wrong alternator on the 1971 Ranchero 351 4V. It's a larger D50F 10300 CA, which is a 1975 70 amp unit of who knows what, I'm guessing truck or something. Problem is, it's physically larger and I'm assuming the distance from the mount bolt hole to the adjustment bolt hole is longer. It just doesn't have enough room in the adjuster bracket when adjusting the belt or when trying to remove the belt.

    So, does anyone know the correct part number and maybe have a picture of one? Thanks and Happy Thanksgiving Everyone!
     
    Last edited: Nov 29, 2014
  2. mo.herbfarm

    mo.herbfarm In Maximum Overdrive

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    Maybe, if the connector (s) fit, it might be usable. mo.
     
  3. Hillbilly

    Hillbilly In Maximum Overdrive

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    Side terminals ? Do the plug in match the alt ? I attempted to use one of those in the low mount position on a 429 Torino and found I could not as it would hit the sway bar. Alternator mounts higher on a 351 so if you had the correct adjuster arm it could work. Extra amperage is always better. Look for the adjuster arm from a 351 / 400M.
     
  4. LSChero

    LSChero In Maximum Overdrive PLATINUM MEMBER

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    Maybe belt is not correct for application.Guessin you have Cleveland.Pic of 72 351C.Happy Thanksgiving to you as well.
    [​IMG]
    Bigger can be better!
    [​IMG]
     
  5. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    If you look closely at the above pics, the adjustment bolt goes through an adjustable bracket; just loosen the bolt at the water pump, adjust the tension, tighten the adjustment bolt then the bracket bolt. There are two styles of alternator connections; the smaller alternators are a rear-terminal setup, and the larger ones have a side-terminal setup with both wires in the same connector.
     
  6. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    BTW, LSChero, the engine in the bottom photo is sweet!
     
  7. F-6Garagerat

    F-6Garagerat In Second Gear

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    It's a 1975 alternator.
    I know how to adjust one.
    I know how the brackets go together.
    It's the wrong alternator.

    If I get the proper alternator I won't need to change anything. I just want a pic and part number of the stock alternator.
     
  8. F-6Garagerat

    F-6Garagerat In Second Gear

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    I don't want to use this one. That wasn't my question.
     
  9. F-6Garagerat

    F-6Garagerat In Second Gear

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    Seriously? I stated we were out of room on the adjustment bracket due to the larger span between the mount bolt and the adjustment bolt. Is there really anyone here that doesn't know how to adjust an alternator anyway??
     
  10. F-6Garagerat

    F-6Garagerat In Second Gear

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    It plugs in fine it's just too big for the bracket I have and would prefer to keep.
     
  11. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    If there's only one bolt hole where the adjustment bracket attaches to the engine, it can be loosened at the engine end where it bolts to the water pump and rotates on that attachment point to adjust for different-sized cases. This is as opposed to the Crown Victoria and Grand Marquis 302/351W, where the adjustment bracket has two attachment holes, so it can't rotate, therefore each of the two casing sizes need its own bracket. The '79 GM that donated its 351W drivetrain to my Chero had the side-terminal alternator, so it had a bigger bracket, which I have kept. When I changed to the smaller rear-terminal alternator I salvaged from my '83 Colony Park wagon, I also had to swap that bracket, using the one from the wagon. I hope that makes things a little clearer on the older engines--they should be able to be loosened at the water pump and rotate to accommodate all sizes.
     
  12. 72GTVA

    72GTVA Administrator Staff Member

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    You might try here - the OSI indicates the part was superceded several times with updated part numbers (later editions of the same part) - the last listing indicates a 1981 part number (E1BF10346BA, E1BZ10346BRM) which Rock Auto shows available here: http://www.rockauto.com/catalog/x,carcode,1141467,parttype,2412
     
  13. F-6Garagerat

    F-6Garagerat In Second Gear

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    When installed, the only way it fits together, there is only 1/2" adjustment left in the slotted end of the lower bracket. The alternator, because of it's sheer size, will not move toward the water pump very far. So, the only belt that works is a 39". It's the only belt that will allow any adjustment while also being able to remove it. I will say this again:

    THE ALTERNATOR IS NOT CORRECT FOR THE VEHICLE AND ITS BRACKETS. IT IS SIMPLY TOO LARGE.

    I just thought someone might have a pic and a part number for the OEM alternator.

    For the record, now discussing GM's with ford engines, mid. 80's station wagons etc. did not "clear things up". I'll figure it out.
     
  14. 72GTVA

    72GTVA Administrator Staff Member

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    Did you not see my link nor post?
     
  15. F-6Garagerat

    F-6Garagerat In Second Gear

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    Yes I did sorry. Thanks I think that may actually help.
     
  16. mo.herbfarm

    mo.herbfarm In Maximum Overdrive

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    Sorry for not understanding. Happens to me often now,,,...........mo.
     
  17. burninbush

    burninbush In Maximum Overdrive

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    @ F6 ... is it possible you could post of a pic of your alternator area?

    And just to get a dumb question out of the way, are you sure the long pivot bolt is in the right hole in the head?
     
  18. Hillbilly

    Hillbilly In Maximum Overdrive

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    Alternator 001.jpg Alternator 002.jpg BB, he has it assembled correctly. There is a difference in the adjuster arm's arc for each alternator. Garagerat want's to run the small case alternator as it is correct for his car and brackets. Anyway, the field and stator connectors are push on style while the ground and 12V lead are retained by nuts. The big case alt. has the terminals on the side of the case. This IS a small case alternator with the wires attached. The adjusting arm is not for a 351.
     
  19. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    That adjustment arm is for an air pump. The one that I pointed out in LSChero's lower pic IS the correct one for all alternators made at that time including the 120-amp Special Service units.
     
  20. inenidok

    inenidok In Overdrive

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    i was having problems on my alt i just broke down and installed a 200amp 3g best choice i made
     

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