Rewiring . . . What would you do different?
 

After troubleshooting a recent short in the headlight circuit, and finding other wires dangling or connected by a single strand . . . I decided I'd rewire the whole beast. That said . . for those who have taken this train already. . . what would you do differently if you had to do it again?

This is not a huge task by any means , but rework can be annoying sometimes. Will use modern 12 gauge wire (black) and install an 8 fuse block for the major circuits.

Re: Rewiring . . . What would you do different?
 

Solder...solder everything, steer clear of crimping connections.

Re: Rewiring . . . What would you do different?
 

I would remove the wire from the light bail to the stoplight switch. And run a new wire direct from either the fuse or the terminal on the firewall to the switch. There is no reason for power to the stop lights to run through the bail.

This way if ever out on the road and a short circuit develops in the bail you can remove the wire from the generator to the bail and continue on in daylight and still have stop lights.

Tom Endy

Re: Rewiring . . . What would you do different?
 

Hi Gents,
Yep, soldering joints and the brake lite wiring are good ideas. I would add a cutoff switch and
also consider turn signal wiring, even if not in use yet, it might become compulsory some time in the future.
I am considering turn signals on both my vintage cars.

Re: Rewiring . . . What would you do different?
 

I think I would just buy a wiring harness from one of the suppliers and be done with it. I have never had a problem with a stock wiring harness. They are correct the right color and go to the right places.

Re: Rewiring . . . What would you do different?
 

Re: Rewiring . . . What would you do different?
 

In my case I've chosen black so that the new wiring will closely match the color of the old wiring . . . today. I've not yet found a modern harness replacement that follows the original color coding.

Re: Rewiring . . . What would you do different?
 

Only way to go!!! If you have problems on road trips you can get help from those traveling with you because it matches the wiring diagrams!!!

Re: Rewiring . . . What would you do different?
 

A pic of what spurred my interest in replacing the wires. Especially the headlight wiring. Years of being soaked with coolant and oils from the engine. The core wire strands inside are covered in an almost black patina. Once all of this is removed I'll cut into the harness at sections to see how far the oxidation goes. The connections here were all soldered (albeit poorly) at some point. They took your advice . . . even back then. ;-)

Re: Rewiring . . . What would you do different?
 

I do my own wiring harnesses. As I don't enter judging, I don't need the correct cloth covered wiring. I buy auto wiring, I add fuses, and because mine is a RHD, I use relays to reduce the current going through the light switch. The switch sits directly under the carb, so I want to reduce the chance of a fire if the carb has a small leak. I have a panel that is mounted on the LHS of the firewall, using the tank to firewall bolts. This way, there are no extra bolt holes, and it can be easily returned to stock by unbolting the panel. I also have LED indicators and a kill switch that sits just behind the gearstick at floor level. If something goes wrong, just reach down and kill the electricals.

Re: Rewiring . . . What would you do different?
 

I agree with the soldering/shrink tube, cutout, and stop light idea. And I like wiring things myself too. I would just stuff the wires in an 'old timey' woven loom. I also prefer to wire the ignition primary circuit more to modern/newer type of wire positions. I'd rather have the coil 'after' the switch.

Re: Rewiring . . . What would you do different?
 

The wiring on mine was in very poor shape, many times spliced together and paper (freezer)? tape used to wrap it. The tail/brake light wire was ran the wrong way (around, over) things and was not long enough. There were three sets of plugs and wire about a foot long added to the end of it as extensions with paper tape. :eek:


I do have a question,,,,,, my head light sockets I guess have been replaced and the wire,, not the plug would fit in and a screw tightened to hold it. The plugs on the new harness will not fit in these sockets. What would you fellows do,,,,, cut the plugs off and strip the wire and insert or do they make socket transitions that would do both????

Not doing a show car so that doesn't matter but I hate to destroy the end of it in case the next owner would like to restore.

Re: Rewiring . . . What would you do different?
 

Can you post a pic of the socket and plug?

Re: Rewiring . . . What would you do different?
 

The plug on the light wire is just the standard plug that was original on the model A. Plug may not be the correct name but it's the same for the horn and tail lights. The sockets for my headlights is probably more modern. With it you would strip the wire and with the wire exposed, stick it on the socket hole and tighten a small screw on the side. Similar/exactly to wiring a trailer connector.

Re: Rewiring . . . What would you do different?
 

Dont know if this will spawn ideas . . . a previous owner had new sockets adapted to the old wiring by soldering and heat shrink just before the socket. The new wires are just pushed through what may have been a socket. The little brass tubes are just that . . . tubes that the wires pass through.

Re: Rewiring . . . What would you do different?
 

First. Remove all electrical tape and butt splices (scotch lock and wire nuts included) and throw as far as you can.

Re: Rewiring . . . What would you do different?
 

You're off-topic with the OP. Start a new thread and add pics so we know what you're dealing with exactly.

Re: Rewiring . . . What would you do different?
 

If you are determined to use the one colour wire for everything, do yourself a favour and buy an assortment of coloured heat shrink tubing. Cut short pieces and use it to colour code both ends of each wire. Simple.

Re: Rewiring . . . What would you do different?
 

12 AWG should be used between generator, ammeter and battery. 16 AWG is sufficient for everywhere else. Using the same color everywhere makes troubleshooting harder. Choose your poison.

Re: Rewiring . . . What would you do different?
 

Good observation. Granted, they could have just as easily connected at the relay, or the junction/terminal box. Of course that would cost a few extra feet of wire. Multiplied by 4,858,644 (more or else), that comes to 1840 miles of wire. :eek:

Re: Rewiring . . . What would you do different?
 

I will be rewiring my Coupe, so here is what I will repeat and what I will do differently:
>Repeat replacing original headlight connectors with three prong modern connectors;
>Repeat adding extra wire support clips on the frame rails;
>Use a main harness with the integral turn signals;
>Add power terminal strip on the inside of the firewall attached with commercial Velcro to run electrical accessories;
>Reroute the dome light power wire to prevent its being pinched at the A Pillar;
>Use jumper wires to assure grounds of 2 OHMS or less from the battery's ground terminal to the car body, the engine & transmission, the ignition points & condenser body, the spark plug bases, the headlight shells, cowl light shells, tail light shells, dome light shell, the instrument light bracket, the steering column housing, and the horn;
>Repeat using 12V with a negative ground;
>Repeat a battery cutoff switch;

>Add a power panel with USB ports and plug ports, so I can use GPS and charge cell phones.

Re: Rewiring . . . What would you do different?
 

I would not suggest using any wire less than 14 gauge on a 6 volt system. I rewired my car and used 10 gauge up to the fuse block, 12 gauge for headlights and wiper motor and 14 gauge elsewhere. Remember with a 50 watt headlamp, the current at 6 volts is more than 8 amps. 10 feet of 12 gauge is about 0.02 ohms, so the voltage drop in the wire alone is nearly 0.2 volts. 16 gauge is about 3 times the resistance per foot which means 0.6 volts is lost. Don't forget there are losses in the switch and the connectors. Nearing 1volt loss is quite a chunk out of the 6 volts total.

If you want to flash indicate the stop lights, you must run the brake lights to the direction indicator switch or else the relay.

I color coded the cables but only used modern wire matching as closely as possible the original Ford plan.

I also added a bakelite 4 fuse box replacement normally used for a Volkswagen Beetle because it looked "period". I mounted it on the firewall next to the central junction box for power distribution after the ammeter to four individual fuses for lights, direction signal, horn and wiper motor.

Wiring is fully loomed: no loose strands anywhere.

Re: Rewiring . . . What would you do different?
 

Certainly nothing wrong with heavier wire size, but it has diminishing returns. As Penthode points out, the major loss is in switch contacts and connectors. Which makes a case for converting to 12 volts. Since 12v components use half the current of 6v, the voltage drop across the same network is also half, which produces only 1/2 x 1/2 = 1/4 the power loss.

Re: Rewiring . . . What would you do different?
 

I don’t recommend complete rewiring a car unless you have had some schooling in basic electricity, wiring and Ohms law..

Crimping versus soldering needs to be COMPLETELY understood. Both are good and there are
places where each will excel. If crimping is to be even considered, a PROPER tool is required. This is a complete closure type where once started the tool can not be opened unless is is compressed to the maximum before it will release. This is the point where metal migration takes place. A requirement for a proper crimp. Crimping is preferred over soldering for people with limited soldering experience.
A good looking solder joint mechanically is not necessarily a good one electrically.

Wire gauges need to be understood for proper current flow to the various appliances. Too small and the appliance will not operate properly and there will be risk of fire. Too big and the cost will go up and there will be mechanical problems like getting the wires through tight spaces and around corners.
Following the factory wire sizes for a given appliance is a good rule of thumb.

In cases where there is room and you are not restoring original, it is a good plan on vintage cars, to run a separate ground wire to each appliance so you don’t rely on rusty frame joints for a ground. All grounds can be brought back to a common centrally located terminal strip and the main ground made close to or at the battery. The ground wires should be the same size as the hot wires.
A fairly common way to handle the hot wires going out is a terminal strip located at some convenient place with one side all hot and the other side for the individual circuits. If you use circuit breakers they can be mounted directly on the strip.
Each hot wire should have an appropriate fuse of circuit breaker.

Over the years I have wired a couple hundred cars from scratch and I prefer Mil Spec Teflon covered wire for safety reasons. It has a very high flash point and it is usually silver plated for better conductivity and corrosion resistance. It is also cheaper if you get it from the many surplus stores around the country.
I use the small number band tape on each end for circuit ID.

Re: Rewiring . . . What would you do different?
 

I start off by using a wiring harness built to factory specs by Sacramento Vintage Ford. I also alter this by wiring straight thru the headlight sockets so that they are terminated in the radiator shell. At the same time I run a dedicated ground that terminates at the battery for the headlights.

For additional circuits I have added, I use 14 gauge color coded wire.

I have a separate terminal fuse block, 6 circuits are switched with the ignition and 6 are on all the time. (see picture)

For all the terminations, I use a crimp tool, utilizing bullet type connectors everywhere except those that terminate at the fuse block.

Re: Rewiring . . . What would you do different?
 

One thing I did that made my car run reliably is to add a second ground from positive post of battery to the Transmission. Original from post to cross member looks good but doesn't help engine operation with all the rubber mounting.


Dale

Re: Rewiring . . . What would you do different?
 

Your original wiring was black?

Re: Rewiring . . . What would you do different?
 

Mine was the original cloth covered harness. In the end I used modern red, green, white and black wire. I considered fusing individual circuits but the excess wiring held little benefit. Ended up with three main fuses only. Put all wires in black loom. It's amazing how basic the wiring is once all the nasty wiring was removed. Took the most part of a morning and afternoon to complete. There's about six inches of original wire running to the each of the cowl lights. It was in fine condition.

Re: Rewiring . . . What would you do different?
 

Perfect reproduction wiring harnesses:

Tyree Harris
Bumpass, Virginia
[email protected]

Re: Rewiring . . . What would you do different?
 

I suppose I could put it back in. :D


FYI: This wiring project was finished back on the 26th of October. Thanks to everyone that chimed in. All great ideas . . . except for the idea of going back to cloth covered wires. I'll leave that to the next owner.

Re: Rewiring . . . What would you do different?
 

buy a new harness and solder in the original light bail plate.

Re: Rewiring . . . What would you do different?
 

Take a good look at how the wires were Mashed up into the old Wrong Base Housing.. Still the same I guess ??..

Re: Rewiring . . . What would you do different?
 

?????? Feel free to explain . . . anytime. All the wiring in the vehicle is now modern. Getting her ready for a blown V8 and chop that top. You'll love the digital dashboard we're planning for her.

Re: Rewiring . . . What would you do different?
 

I have seen references to Sacramento harnesses in numerous posts over time. Does anyone have specific knowledge if they are really more quality than those sold by our most reliable parts dealers?

Re: Rewiring . . . What would you do different?
 

The 3rd Picture in Your Post #30 says it all !!..

Re: Rewiring . . . What would you do different?
 

Thanks for the information. thanks again for helping me rebuild my rearend in vancouver.

Re: Rewiring . . . What would you do different?
 

Yeah, that was prior to the wires being replaced. I think the picture was perty good, considering the lighting and that it was taken with a phone camera. Not optimal, but good enough to get the point across.

Re: Rewiring . . . What would you do different?
 

Yup, I got the "Point", You did Not !!..

Re: Rewiring . . . What would you do different?
 

Re: Rewiring . . . What would you do different?
 

I just changed out my main harness this year, bought it from Sacramento Vintage Ford.

I didn't have to modify the light switch terminal disk at all. Plugged right in, worked perfectly from the get-go.