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New Wiring Harness Question

Discussion in 'Early CJ5 and CJ6 Tech' started by peter mellen, Jul 10, 2022.

  1. Jul 10, 2022
    peter mellen

    peter mellen New Member

    new hampshire
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    Jun 19, 2022
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    I recently purchased a 1956 CJ5. The headlights, brake lights and directional lights do not work and under the dash is a rats nest of old and new wiring.
    upload_2022-7-10_13-13-15.jpeg
    It has been converted from 6v to 12v and has what appears to be a one-wire alternator, as there is a voltage regulator on the firewall but there are no wires going to it.
    upload_2022-7-10_13-14-51.jpeg
    I think the best path forward is to order a new harness from Walck's. My question is, what harness should I purchase? Should I purchase a copy of the original 1956 6v harness or a 1957 harness, which is when I believe Willys changed the electrical system from 6v to 12v, or a later harness?
    Walck's philosophy appears to be restore the vehicle back to its original systems, but since this vehicle has already been converted, wouldn't it be simpler/easier to install a harness designed to work with an alternator?
    Any advice would be greatly appreciated.
     
  2. Jul 10, 2022
    rusty

    rusty Well-Known Member

    norfolk,va
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    Short answer, yes. Take a look at ez wire.
     
    tcfeet likes this.
  3. Jul 10, 2022
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    Welcome from Boston metro.

    Does not look bad to me. I'd just fix it. Jeep harnesses are very simple - read the wiring diagram and take it one circuit at a time. Anything that's been added and broken can be removed and fixed.

    Three-wire Delco 10SI has the regulator inside, as you noted. I'd use the factory diagram and remove the regulator wiring. The yellow wire is the voltage sense wire, and can bend back to the battery connection, as here. The other wire is the exciter, and connects to the ignition through a light bulb, diode, or resistance wire.
     
  4. Jul 10, 2022
    Mcruff

    Mcruff Earlycj5 Machinist

    Albertville, AL
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    Ez wire, far cheaper than any other harness, great harness, labeled and color coded. I installed mine back in 2005 and never looked back. 12 circuit harness is all you need. Your headlights will be brighter than ever due to relays and such.

    https://www.ezwiring.com/
     
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  5. Jul 10, 2022
    Oldpappy

    Oldpappy A.C. Fults - Curmudgeon at large 2022 Sponsor

    East Tennessee
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    That is a 3 wire alternator which has been jumped back to the positive post, a very common practice.

    Wiring on these old Jeeps is pretty simple, but if you are uncomfortable with following a diagram the harness Walcks produces is very well made. One came in a box with a CJ2A I traded for and I am going to use it on my project Jeep, but I usually just make my own. The 67 CJ5 I have had suffered a fire under the dash which burned a lot of the wiring along with the cardboard defroster duct. I downloaded a wiring diagram for a CJ5 and re-wired it in a couple of hours. It was easy.
     
  6. Jul 10, 2022
    boopiejones

    boopiejones I can’t drive 55

    California east bay
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    I have a 56 that had way worse wiring than yours. I ripped it all out, bought some spools of wire and a bluesea fuse panel and rewired the whole thing myself. I had never done anything like that before. It’s surprisingly easy on an old Jeep.
     
  7. Jul 10, 2022
    Howard Eisenhauer

    Howard Eisenhauer Administrator Staff Member

    Tantallon, Nova...
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    I have the Walcks harness & I consider it money well spent, the nice thing is it comes with new bulb sockets for the instrument lights and connectors. If you call Carl W. before ordering he can build the harness to work with the alternator of your choice.
     
    Fireball and dozerjim like this.
  8. Jul 11, 2022
    Rick Whitson

    Rick Whitson Detroit Area 2024 Sponsor 2022 Sponsor

    I live South of...
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    Welcome from Michigan. I used a factory 66 V 6 harness but wish I had put in a fuse panel, it had inline fuses now if I have a problem I have to find the inline fuse that has the problem. I added electric wipers, a radio, interior light, and a siren, all inline fused. That was 13 years ago, today I would do it different. I would put in Bluetooth speakers today instead of a radio. Good Luck.
     
  9. Jul 11, 2022
    Walt Couch

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

    cordele, Ga.
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    Welcome.
     
  10. Jul 11, 2022
    Buildflycrash

    Buildflycrash More or Less in Line. 2024 Sponsor 2022 Sponsor

    Gulf Breeze FL...
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    EZwire is way cheaper and their 12 wire kit is all you’ll need. I have it in one jeep and it’s going in another soon.
     
  11. Jul 11, 2022
    PeteL

    PeteL If it wasn't for physics, and law enforcement... 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Hills of NH
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    They didn't exactly change it. Voltage was optional for a while, I believe.

    A six volt system has heavier current capacity, so it will easily handle twelve volts.
     
  12. Jul 11, 2022
    PeteL

    PeteL If it wasn't for physics, and law enforcement... 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Hills of NH
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    Yes. Just because the wires aren't all neatly bundled and tightly wrapped just means they are easier to trace and work on.
     
  13. Jul 11, 2022
    Oldpappy

    Oldpappy A.C. Fults - Curmudgeon at large 2022 Sponsor

    East Tennessee
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    That wiring is in a lot better shape than what I usually find. The advantage of a CJ5 compared to earlier Jeeps is the removable dash. On mine I unbolted the dash panel and laid it on the steering column where all of the wiring was easy to get to. I downloaded a wiring diagram I found on this site and taped it to the windshield where I could see it while I sat in the driver seat with my wiring kit. I put a piece of scrap plywood under the windshield, and used the windshield to clamp it in place, to set my soldering iron on. I spent about two hours repairing, replacing, and removing the excess wiring the PO had use for various add on equipment. It was the add on wiring that caused the under dash fire. This beats heck out of having to contort upside down on the floorboard to get to the wiring on a flat fender Jeep.
     
  14. Jul 11, 2022
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    Yes, wire is sized by current. If you double the voltage, you get the same power from half the current. If you change to 12 volts from 6, the existing wire is twice as heavy as it need to be.
     
  15. Jul 11, 2022
    Mcruff

    Mcruff Earlycj5 Machinist

    Albertville, AL
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    It also means there more likely to get damaged when not bundled up and in a loom or chewed on by little critters.
     
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