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Cj 5 1957 Generator To Alternator

Discussion in 'Early CJ5 and CJ6 Tech' started by Island CJ5, Mar 31, 2021.

  1. Island CJ5

    Island CJ5 New Member

    Where can I find out what to do with the 3 wires remaining on voltage regulator when I put alternator in and removed the generator? Thanks
     
  2. Jw60

    Jw60 That guy 2024 Sponsor 2023 Sponsor 2022 Sponsor

    What alternator did you go to?
    On mine I used a 3 wire gm alternator and everything to the regular to body hooked to something on the alternator.
     
  3. boopiejones

    boopiejones I can’t drive 55

    PeppyCJ6 and tcfeet like this.
  4. tcfeet

    tcfeet Member

    Switched mine over 10 years ago, did away with the regulator and rats nest of wires on the firewall.
     
    Jonbbrew likes this.
  5. Jonbbrew

    Jonbbrew Member

    Ditto x2 but more recently. Much cleaner and simple. Delco 10si. Did not have a wiring harness as I rewired the entire Jeep from scratch. Internally reg is the way to go.
     
  6. 47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

    I used a generator on my first 2a. The voltage was incorrect and since the regulator was mechanical I could adjust it and clean the contacts.
    I had an alternator on my 225 and a separate regulator. It was fine, but I needed more power to run an electric fan.
    I installed a one wire 94 amp chevy alternator. It worked fine as well. take your pick 1984 CHEVROLET CAMARO 5.0L 305cid V8 Alternator / Generator | RockAuto

    None of them are better than the other unless you need more power. All the hype about "One Wire" is not relevant. They are the pretty much the same to wire up but the battery light doesn't work if you dont do it correctly with the GM one wire.
     
  7. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    If you go with a one-wire alternator, the regulator is in the alternator. It is really one wire: you connect the charge wire to the battery. The one wire alternator is a modified Delco 3-wire alternator. The 3-wire has a charge wire (charging the battery), a sense wire (reading the battery voltage to control charge current) and an exciter wire (providing the initial trickle of current from the ignition switch). The one wire changes the regulator design to eliminate the sense and charge wire.

    Most 3-wire applications immediately tie the sense wire back to the charge wire right at the alternator plug, making the 3-wire into a 2-wire.

    This does not make sense to me. With the original Delco 3-wire, the ALT light is in series with the exciter wire. With the key on and the engine not running, the alternator is a sink of the exciter current, and the light is on. Start the engine and the alternator is now self-generating, using its own output to make more current. Now both the ignition and the exciter are held at full battery voltage, and the ALT light goes out.

    You can't have the ALT light and a one wire alternator. I presume you could somehow put the exciter wire back and have an ALT light, but then it's no longer a one wire alternator since it now has two wires. You may as well buy a 3-wire from a Delco automobile application, connect the sense wire back to the charge wire to make a 2-wire, at half the price of the fancified one-wire aftermarket product. You then also get whatever warranty the parts store gives with the alternator, and easy replacement if needed.

    To the OP, if you have a one-wire to go in your Jeep, just eliminate all the regulator wiring. If you need to, print out the wiring diagram and trace out the wires to remove. You only need a wire from the battery to the alternator: that is your entire charging system. If you have an ammeter, it can no longer be connected. If you have an alternator light, it will no longer work. You can add a voltmeter if you want to check on the charging system from the dash.
     
    Last edited: Apr 1, 2021
    47v6 likes this.
  8. 47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

    Some people have had issue with the Alt(battery) light when retrofitting a GM "one wire" into a stock cj5. There are multiple posts about this issue and people want them to work. Some people have successfully made this modification and you most likely have helped them achieve this endeavor.
    Catalog

    Very first link from 2004 on a google search where using the terms Early CJ5 and one wire alternator i alternator conversion
    And you replied Tim!
     
    Last edited: Apr 1, 2021
  9. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Chris, I don't want to argue with you, but it's not an issue. It's intrinsic to the one-wire alternator design. You lose the capability for an ALT light with a one-wire alternator. Write me a diagram that has one wire to the alternator and a light and I'll be wrong.

    I have learned since that 2004 post. The voltage drop is unrelated to the load resistance. It's actually the voltage drop due to the internal resistance of the battery that the alternator is sensing. Mostly does not matter where you connect the sense wire.
     
    Last edited: Apr 1, 2021
  10. Island CJ5

    Island CJ5 New Member

    Thanks for the replies. Yes I have installed a GM 3 wire setup. My main issue is the 3 wires on the old external regulator that I am trying to remove. I am not sure what to do with these? The old generator and wires from regulator have been removed. Thanks again.
     
  11. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Are you still in doubt?
     
  12. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Point to specific wires if you need to -

    regulated (871 x 586).jpg
     
  13. Island CJ5

    Island CJ5 New Member

    I thought I could remove the regulator. It has two red wires and a black wire on the regulator. I connected the white wire from alternator harness to ignition starter with fuse, the pacer wire to battery, the red alternator wire to battery with 100amp fuse.
     
  14. Island CJ5

    Island CJ5 New Member

    Should I just leave the regulator connected?
     
  15. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Depends on your preference.

    If you have the 3-wire alternator, it has a plug with two wires and the big charge wire. #2 on the plug can go right back to the big battery wire. #1 can connect to the ignition switch via the ALT light or a resistance wire or a diode. Everything else can go away.
     
  16. Island CJ5

    Island CJ5 New Member

    So when you say everything can go away. Do I just connect the two old red wires on the old regulator together and what about the black one on the old regulator?
     
  17. Island CJ5

    Island CJ5 New Member

    That was my original question but I was not clear.
     
  18. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Show us the new alternator. We are assuming it is a modern Delco unitized alternator with three wires.

    I would remove the old regulator and all the wires to it, back to their origin. There is a regulator inside the 3-wire alternator, and the old regulator has no function other than leaving a bunch of wires dangling that could short out.

    The white wire should be marked "1" on the alternator case. Without a bulb or a diode or a resistor in that wire, your Jeep probably won't shut off with the key.
     
    Last edited: Apr 3, 2021
  19. Island CJ5

    Island CJ5 New Member

    I looked at few wiring diagrams and seems like the red wires feed the lights and the black one feds the custer amp indicator. Thanks
     
  20. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    :confused: What?

    Did you read what I posted?