The Stovebolt Site Forums The Shop Area The Electrical Bay Wiring harness replacement - what do I need ('53 3100)

Looking for some advice/input on what all I need to change over the wiring harness on my 1953 3100. I recently picked up a new (Rebuilt 235 engine) with HEI, electric choke and 65 AMP 1 wire alternator. The truck was previously converted to a 12 volt generator system but from what I have noted they did a really quick job and did not make what I would consider good choices for connecting wires. I have not had any electrical issues but I really never looked at the wire connections until I had to move them to take out my engine. There is no of heat shrink, solder or even crimp connectors used. They just twisted wires and put some electrical tape over the connection.
Now that I am going to the alternator I knew I needed to add some safety features to the system. Looking at what I have tells me it will be better to start over with a new wiring harness. I have seen a number of wiring harness's recommended on this site and I will likely pick one of those to use (12-14 fused system). I also thought I needed to put a 40-60 amp relay in that energizes with the ignition and then feeds the fuse box.
The 1 wire alternator seems simple enough but I did see where someone mentioned the need for an AD (? ) plug in one of the threads here on this site. Not sure what that is and have not been able to relocate the thread I found it in. Will I need this plug or can I just wire the alternator as a single wire? Do you suggest taking the old wiring out and starting from scratch or pull sections of wire out one at a time and rewire as I move along.
Thanks for any suggestions.

DEEGS

Wonder if anyone can help Deegs with his question?

Sorry I can not provide a lot of direction but with your alternator conversion you will no longer need the voltage regulator shown in your first picture.

As you already noted you will need to fix all the previous owner's wire splices but also agree you should know the full scope of what you need to do before you get too far into that.

I am sure someone with more direct expertise will provide feedback shortly.

Man, I would highly recommended starting fresh with new wire.
Frame ground it all. I am by far no expert. I have completed 2 without much problems other than

finding a proper ground sometimes due to paint and rust can be frustrating.

With those twisted wire connections, it sounds like a new harness is in order.

I also have a 235 with HEI, one wire alternator and a 12 volt conversion. I wired mine with the intent of installing a new 12 circuit harness and I’m getting near that point

From what I have gathered on this forum, don’t cheap out on the harness as the wires may not be labeled, connections are shoddy and the instruction are non existent. A highly recommended harness is a 12 circuit harness from Speedway.

A one wire alternator does not need the DA plug, but a three wire may be a better choice. You should read the pros and cons before you make that decision.

With that HEI you’ll need to modify any harness you may purchase as it needs a 10 gauge supply. I installed a 60 amp relay for the HEI.

Hopefully some of the electrical gurus will come along to provide additional guidance. Good Luck and keep us posted!

Thanks for the feedback. I have been looking at a number of threads on this site and watched numerous videos on line. Had to quit as it was becoming too intimidating. The two harness's I am looking at now are the 14 circuit from Haywire and the 12 Circuit from Speedway. Not sure what direction I will go but I will post updates and pictures as I proceed.

Deegs

Update. Wire harness is removed. It was intimidating as I began but then after noting three bare wires that were not touching bare metal only by the fact they were sitting on top of another wire. Now I am glad I took this on and removed the old wiring. Also figured out why my dome light did not work. That wire is bare where it enters the channel to go over the door and it is touching the metal.
I purchased the Haywire 14 Circuit wire harness and will begin the install as soon as I complete painting the engine bay.
Another thing I noted is there were no voltage restrictors to be found and the truck was upgraded to a 12 volt generator. The fuel gage and ammeter appeared to work as required.

Deegs

When putting the harness in. Take a the fuse box leave it at the foot of the seat. Then pull your wires. Then when pulls are complete and it’s how you like it. Then mount your fuse box where you can easy unhook. This allow two things. Spare wire on runs when you need it. And easy get pull fuse box out too get to wires ore check fuses. Trust me not having to go under dash all over and over is nice when working wires. Having extra wire is nice when you need to move stuff later.

Thanks for the tip. I was planning to install the fuse box first. Now that you mention it I realize that makes life difficult for me.


Deegs

Need a sanity check. I am finally beginning to pull wires in with the new harness and I noted there are a few wires in the harness marked for a neutral safety switch. I marked the wires coming off my ignition switch and did not note any for a neutral safety switch. I just want to be sure it is not tied in somewhere else because I plan to remove these from the harness if they are not required.

Thanks
Deegs

It might be hard to wire in a neutral safety switch on your AD, although a clutch pedal switch could be used (closed when the clutch pedal is fully depressed.) But either one of those only work on a solenoid operated starter. If you have a stomp starter then all bets are off on wiring one in.

Modern vehicles use these to prevent idiot drivers from starting a car in gear, along with other features like lane departure, blind spot warning, etc. to protect the rest of us from incompetent drivers.

I think it'd be OK to leave those wires out.

IF there are two wires and IF your transmission, clutch pedal and/or shift linkage does not support a neutral safety switch you should tie the two wires together to simulate that the tranny is in neutral/park or the clutch is pushed in.

Kevin
Thank you. I wanted to make sure I did not miss something when I removed the old wires. I took my time to trace them before removing but when you are upside down missing a hidden wire would not be difficult.

Deegs

1. Neutral safety switches are for automatic transmission. Don't need that.
2. You ALWAYS push the clutch in when starting. Foot on brake or park brake on.
3. I don't recommend "removing" any harness wires from harness or fuse box. They can be used for any add on's. The markings on wire and fuse box don't matter. Roll up the wire, tie wrap it and tuck in under.
4. No need for a relay. Why?
5. Whether harness covers this or not, it's simple.
One wire from keyed hot to HEI pos.
One big fused wire from battery to alternator.
Fuse box power is wired per instructions. I can't open any of your pics.TOO SMALL.
If you need help along the way, post instruction sheets.

Speedway harness was MUCH cheaper?????? 17 feet long for trucks. 22 circuits. Free shipping. $180

Bartamos,
Thanks for the feedback. I know the speedway harness was much cheaper than the one I purchased from Haywire and hindsight being 20/20 I probably should have went with a smaller harness since I have no desire to add things like pwr windows and doors, HVAC or cruise. I just watched too many You Tube videos on this subject and got caught up in the sales pitch for haywire.
I did harvest some wires out of the harness connector that screws on to the fuse box. I set them aside for later if there is ever a moment of insanity and I want to add those items. The connector is marked as well as the wire so the reinstall would not entail a great deal of work. I did keep some of the wiring I do not have a need for such as the curtesy lights and cigar lighter. I am going to add a charging outlet for my phone and hide it in the glove box.
I also purchased a low voltage module with a warning light from Blue Wire, awaiting arrival of that item. I am certain I will have more dumb questions as I proceed. Progress is slower than I had hoped it would be and I seem to spend more time scratching my head than pulling wires in. I believe I am at a point now though where I will make better progress with the install since I am done harvesting unneeded wires.

Deegs

Had a question I hope I can get an answer for concerning the dome light wiring set up. I noted the dome light was grounded to the cab of the truck via the frame of the dome light. The new harness I have has a separate wire for power and ground. Looking at the way this dome light is set up I am not sure I need two wires, but I would like to change the current set up (no pun intended) because the wire going into the socket for the bulb is really worn. I did some searching on the web and found some dome lights on the Filling station site but the size they give for the lights make them too large for my use. 1953 3100. Any suggestions?

Deegs

Deegs, There are a whole bunch of our regular vendors offering reproduction lights that are direct replacements. Classic Parts offers both a Chrome unit or a Painted unit for the same low price. No reason you can't use one of these and simply attach the new harness ground wire to one of the light base mounting screws (cleaned of paint to promote the best ground) when you install it to the existing opening.

You could even use only the new lamp base/switch assembly and install your old light cover and lens plate to keep any patina look if that is what you are going for. The new fixture base and switch elimnates the damaged existing wires in your old unit.

I was considering a replacement light such as Gdads51 suggests but decided to "rebuild" my original. I replaced the switch that did not function correctly with a rocker type I found on E-Bay by modifying the bezel and base to a rectangular hole and replaced the wire from the socket button to the switch by soldering a replacement wire with heat shrink tubing to the old wire core near the button. I do still need to modify the opening in the cab slightly to clear the new switch but it preserved most of the original look with improved electrical components.

Gears 51 / WICruiser,

Thanks for the info. I like having options and y'all just gave me a couple of them.🤔

Deegs