12v conversion - you can hang me for not using search

Hey guys,

I actually did do several searches and read several threads on the 12V conversion. I've digested the opinions and am determined to push forward with a 12V system.

My questions begin with, when converting, do most people also convert to negative ground rather than positive? Park's 4 page write up suggests it as the picture on the bottom of page 4 shows the negative battery terminal connect to chassis ground. I haven't seen a whole lot of color related to this. I'm not electrical expert, in fact  really only vaguely understand it at all. So the first question is what else so I have to change if I am changing to 12V negative ground. I mean won't some things run backwards?!

Do most people just totally rewire the car when undertaking such a conversion? Is there a kit or harness for this? Most of my wiring is original (read: frayed and corroded).

How exactly does the Delcotron 10 SI Series alternator fit? It just so happens to have the correct pulley size and alignment?


I am sure I'll have more questions as you guys respond.

Comments

  • ratlee2
    ratlee2 Expert Adviser

    When I converted my wasp to 12 volts I was in the process of rewiring as well.  I had the original generator rebuilt to 12 volts, but I gave up on that after replacing a couple voltage regulators.  I installed a mid 80 10SI alternator from a firebird and purchased a new wire pigtail and pulley.  I was able use the upper mount and part of the lower mount.  I just made a new u-shaped bracket to out of a piece of scrap metal I had laying around.  Wiring was pretty easy.  I used an article in car craft magazine that had a diagram similar to this one.  I went negative ground just for consistency with other cars.

    Image result for 10si wire diagram    

  • hudsonguy
    hudsonguy Senior Contributor

    To answer a couple more questions;


    When I converted I did indeed switch to negative ground, as well as replace the wiring harnesses in the car, as they were badly frayed, etc. You can get them at Rhode Island Wiring, or other places.

    The pulley that comes on the alternator is too narrow for a wide belt used on a Hudson, but you can buy a wide belt pulley (Speedway Motors, for example) that will bolt right on and replace the narrow one.

  • Sacksenheim
    Sacksenheim Member
    edited May 2017
    Ok so this one isn't getting a whole lot of action. Lets say I did want to re-wire the car but didn't care for originality. Anyone have any experience with that? Process, vendors, build thread?
  • Jon B
    Jon B Administrator
    edited May 2017
    I guess you could just  yank out the old harness(es) and tack them to a 4 x 8 foot piece of plywood or particle board.  Be sure to verify that the old wiring is long enough to reach each component before removing and note where you want to install new circuits for modern accessories.  Once it's laid out this way it's easier to measure and understand.  Then go down to your auto parts house and purchase the correct gauges of wires (for each circuit), and modern connectors.  Then you can tack the new wires next to the old, on the large board, to match up the new to the old.  You can get plastic or cloth hollow "loom" to hold several wires, when (for example) they run together for a certain distance .... like from dashboard to engine.  Or just tape multiple wires together with black tape.



    If you wanted to spend less time (and you had more money) you could purchase an original style wiring harness from a company like Narragansett, Rhode Island Wiring, or YnZ Yesterday's Parts.

    Here are a couple links to re-wiring advice I found on the internet, but I haven't reviewed the actual suggestions to see if they're good ones.  http://www.lbthosting.com/dutton/others/ReWire.pdf     http://https//www.jalopyjournal.com/forum/threads/do-you-make-your-own-wiring-harness-and-why-with-poll.310184/

    Not meaning to be impertinent, but why are you switching to 12 volt?  Got several modern 12-volt accessories you plan to attach? 
  • bob ward
    bob ward Senior Contributor
    A couple of thoughts. 

    Rewire the car for sure, you are asking for trouble - short circuits or fires - leaving the old wiring in place.

    A DIY car rewire is quite feasible, I did a 53 a few years ago and its still going strong. I bought a few rolls of different coloured wire and a collection of different styles of connectors. You will need a multimeter, a test lead, a good connection crimper and maybe a soldering iron. The soldering iron is possibly overkill but I like to solder connections as well as crimp where possible.

    The wiring colour scheme was very basic, something like red for ignition circuits, green for lighting circuits etc. Put masking tape labels on each wire and leave them there until you are 100% finished. Install a 4 or 6 fuse modern blade fuse block somewhere it is easy to get to, label the fuses. Run the headlights through a relay. Time, patience, a reasonably agile mind, a wiring diagram and more forum reading will get you there.

    Make sure you replace ALL the wiring, even on hard to get to minor circuits such as the interior lights. Unless you have them separately fused, if one of those old wires with flaking insulation touches the shell it will blow your lighting fuse.

    Negative ground is standard for 12V systems. Your +ve ground starter motor (which you should get rewound to 12V) will still keep turning the same way with -ve ground.


  • Jon B. to answer your question, here are a few thoughts.

    First, I want to be able to add vintage air and a stereo. Also, parts and service ability will be greatly improved.

    Beyond that, I ask about the re-wire because the existing wiring is certainly in bad shape. 
  • 50C8DAN
    50C8DAN Senior Contributor
    If you want to add these items, most of the repro wiring vendors will add them into the harness if you ask and tell them the color code etc.  I had Rhode Island add a couple of extra wires for fog lights to my '50C8 harness (still have not added them to the car but the wires are there!).  As noted most will do the alternator wiring change for you as well but you need to be specific as to what you want.
  • Dan,

    How much did your harness cost?
  • 50C8DAN
    50C8DAN Senior Contributor
    All of the harnesses are ala carte so you will need to know what you need.  Most of these guys are competitive but here is RI Wiring. http://www.riwire.com
  • I think for now I am going to find a voltage regulator and just keep it stock. Once I decide if I am keeping it or selling it I will start getting organized for the re-wire.
  • Jon B
    Jon B Administrator
    I think that's a wise idea.  It would be a shame to convert components and wiring to 12 volts at a not-inconsiderable cost of money and time, only to discover that you would prefer another car!  It will cost you very little to patch, tape up, and otherwise get the existing 6-volt wiring system to a safe condition.  Be sure you get the correct gauge battery cable, that you get a battery with a decent cold cranking amp rating, that you have two ground connections (battery to engine, engine to body), and that your generator and voltage regulator are up to snuff.

    Then you can start driving the car and having fun with it.

    Once you start driving this car and are comfortable with it, you can make the big leap to changeover of your system, and the purchase of a new wiring harness.  From what I've heard, I think a complete new harness will run you somewhere between $500 and $1000.
  • Sacksenheim
    Sacksenheim Member
    edited May 2017
    Given that I haven't yet found a regulator in my massive parts haul, where is the best place to source one? It does not need to be restoration correct or NOS. Brazilian and functional is just fine.
  • Jon B
    Jon B Administrator
    No need to go Brazilian, you can get a brand new old stock Autolite for your Hudson on Ebay.  Just verify the Autolite part number for your year of Hudson, there are a couple of cross-make interchanges that make these relatively simple to get.

    Also, you can send e-mails to some of the Hudson parts vendors who advertise in the WTN, requesting the regulator.  While you're at it you might want to list other things you're looking for, so you don't have to e-mail again and again.
  • Is it the VRR 4001a? Some resources seem to say that model number works through 49, others say 50 and still others say 51.
  • Jon B
    Jon B Administrator
    Don't recall the year of your Hudson, but the Club on-line library has a lot of parts manuals and service bulletins available at the Club website, assuming you're registered there.  Also, check Ken Cates' informative Step-Down pages for all sorts of info.  http://hudsonrestoration1948-54.com/   (I don't own a StepDown so can't offer advice!)
  • Jon B
    Jon B Administrator
    I'm looking at a spec sheet on the HET online library.

    The '54 Hornet is shown as having a VBE-6104A voltage regulator.  It is shown as using a GGW-4801B generator, so you might want to be sure you have the right generator before buying the voltage regulator.  (Someone might have put a different one in, at some point).

    I read on the internet that NAPA carries an Echlin #VR27 voltage regulator which is for 6 volt POSITIVE ground, and rated at 42-47 amps.  This, it is said, interchanges with the VBE-6104A voltage regulator.  You might check with NAPA.  Of course, they may no longer sell this, I don't know.

    None of the above information is guaranteed.  With any luck, a '54 owner will jump in here to confirm / deny it.
  • I actually have a '51 and just checked the hudson restoration site, called 21st Century Hudsons and confirmed that I should be able to buy the part at Napa. They show a Echlin ECH VR25 that I am hoping does the trick. That said, I'll take your advice and confirm the generator first. More to come.
  • Jon B
    Jon B Administrator
    Sorry!  Read your "parts for sale" post, and assumed that your Hornet was a '54.