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Which Alternator?

Discussion in 'Early CJ5 and CJ6 Tech' started by chrisg, Nov 18, 2018.

  1. Nov 18, 2018
    chrisg

    chrisg My Flatty

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    Hello Guys, doing some work on the jeep today. It has a Delco alternator and an external regulator. I'm noticing there's no plug on top .(it's actually capped off ) . Not sure what the Amp rating of this one is, because it's not marked. There's only two wires that are connected from starter to alternator.

    My Jeep has a 8274 winch, electric fan, and eventually some kind of lights.

    Is this set up as a one wire? What part number or application would I use?

    thanks,

    Chris
     
  2. Nov 18, 2018
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    Picture?

    With an external regulator, it's not one wire. A one wire alternator literally has one wire, plus the ground through the case.
     
  3. Nov 18, 2018
    chrisg

    chrisg My Flatty

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    Hey Tim, that's what I thought. It's an old delco, the one that has the plug on the top. Btw, the previous owner said that the throttle must be pushed before it charges. I'm wondering if it's because it's not wired correctly.

    I'm changing it because I replaced the lower mount (broken) and it's noisy and maybe bent ..

    How do I post a pic I take from my phone?

    chris
     
  4. Nov 18, 2018
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    You'll have to ask somebody who's more phone savvy if you want to post them direct. I always download pics to my computer and post them from there. I expect you will need to resize them - pics direct from your phone will be too large. I use PixResizer (freeware).
     
  5. Nov 18, 2018
    chrisg

    chrisg My Flatty

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    20181118_165300_resized.jpg
    regulator
     
  6. Nov 18, 2018
    chrisg

    chrisg My Flatty

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    20181118_165435_resized.jpg
    alternator on jeep
     
  7. Nov 18, 2018
    Oldiron90

    Oldiron90 New Member

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    I'm swapping to a 3 wire 12si alternator here within the next two weeks or so. I currently have the 34 or 35 amp Motorola unit.
     
  8. Nov 18, 2018
    Oldriginal86

    Oldriginal86 Member

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    If your going to purchase a new alternator, might as well get one with an internal regulator. Mounting will be the same and the wiring can be simplified.
     
  9. Nov 18, 2018
    45es

    45es Active Member 2024 Sponsor 2023 Sponsor 2022 Sponsor

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    The alternator you have appears to be one that would have been used in the early to mid 1980's. Do yourself a favor and do as Oldiron90 is doing. Get a Delco 10 or 12si series alternator with the amperage rating you want. There are several to choose from. They are internally regulated and only require 3 wire to be connected. There are only about a million wiring schematics on the internet showing how to connect the wires. Example: http://www.mommynotesblogs.com/wp-c...r-of-delco-12si-alternator-wiring-diagram.jpg
     
  10. Nov 18, 2018
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    Mad Electric has a guide to buying a 10SI/12SI Catalog

    Note that clocking these alternators is really easy if you know how. Just ask.
     
    chrisg likes this.
  11. Nov 18, 2018
    Oldiron90

    Oldiron90 New Member

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    Not to hijack but what size fuse would you put between the alternator and battery?
     
  12. Nov 18, 2018
    chrisg

    chrisg My Flatty

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    Thanks for your reply ed... I think it has the 12si on it now. I checked the link sent by timgr, and it shows the plastic pulley, which is a 12si...

    Wouldn't the hookups be one 8 guage wire from battery/starter to alt? then ground terminal on alt to somewhere on block?
    Also, on mine there's NO ground wire. I then could just dis-connect wiring at regulator
     
  13. Nov 18, 2018
    chrisg

    chrisg My Flatty

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    Thanks timgr.. The installed alternator looks like a 12si.... and a 7278 or 7294, it would be amperage difference. Have you used one of these before? I don't need one of the chrome ones, but I've seen a few new ones starting about 60 bucks. And some well over a hundred. NAPA sells for about 90 dollars

    chris
     
  14. Nov 18, 2018
    chrisg

    chrisg My Flatty

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    Simplify is a good thing brother, appreciate it . Chris
     
  15. Nov 18, 2018
    45es

    45es Active Member 2024 Sponsor 2023 Sponsor 2022 Sponsor

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    A fuse is not normally used between alternator and battery. But, a fusible link is. As in my case, my 10 gauge battery cable is protected by a 14 gauge (red or rust) fusible link. FYI: I'm using a Delco CS130 105 amp alternator. A fusible link is a wire 4 gauges smaller than the wire you are protecting.
     
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  16. Nov 18, 2018
    chrisg

    chrisg My Flatty

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    ed, I used a CS series alternator in my boat and it worked great. The ski boat had two amps, one for subs, and one for speakers. When i got it it had a 40 amp unit on it, didn't charge worth a crap. Didn't think of that, i had the CS built at a local rebuilder. Think I'll call him tomorrow. Appreciate your help, Chris
     
  17. Nov 18, 2018
    45es

    45es Active Member 2024 Sponsor 2023 Sponsor 2022 Sponsor

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  18. Nov 18, 2018
    chrisg

    chrisg My Flatty

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    hey ed, appreciate your reply. Not sure how it's connected to the REG, its wrapped. And the only connection to the ALT is two wires from starter... But, looks like two of the wires go to the starter. I'll look at it tomorrow.. thanks again, Chris
     
  19. Nov 19, 2018
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    It can't be a 12SI if it uses an external regulator.
     
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  20. Nov 19, 2018
    Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

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    Chris these things can be confusing as all get out depending on what the PO has hidden. Your alternator could have been altered with a 1 wire internal regulator and the regulator you are showing is not really functional. The previous owner (PO) may not have known quite what to do and just left the old regulator as is. Is the alternator charging at this time?
     
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