47-55.1 1954 Chev 3100 Wiring Woes

[Darthintel]

I recently purchased a 1954 Chev 3100 truck and started working on the wiring problems. I had no parking lights, no left blinker, and right blinker flashed the right front parking light, and left rear light - wow.

First off I worked on the parking lights. Turned out the previous owner painted under the parking light housing insulating the ground. After fixing this, I noticed the left front parking light was wired to the bright filament. Swapped wires.
Now with both front parking lights working, I then swapped the rear blinker wires. Finally parking lights and blinkers working.
Additional wiring problems that need to be replaced and provided pictures below.

I noted the horn is not working. I took a ground jumper wire to the relay and it switched - power is connected to the relay and applying ground switches the relay. When I depress the horn button, nothing. I found the wire exiting the steering column just under the dash and it has a wire attached to it. I checked the wire, and it has a constant 12V! Now, the wiring diagram shows this wire to be switched to ground when the horn button is depressed. Mine is connected to a constant 12V! I cut the wire disconnecting the 12V. I'm thinking the contact in the steering column is burnt as the wire was connected to 12V, and depressing the horn button shorted it to ground.
I still can't believe this.
I love to do wiring, and will be tearing out all wiring and replacing it.

I also will be using relays and running grounds to everything.

[MiraclePieCo]

Sounds like a new harness may be the best course of action.

BTW, do you still have the tires that came on your truck? I'm looking for a pair of 255/60R-15. Looked like those might be close.

[Darthintel]

I have purchased a new distribution panel / fuse box and will be creating my own harness using GXL wire. These trucks are simple. Also I'm adding relays for the headlights and running new grounds.
Previous owner converted to 12V but still has the 6V generator on it which didn't work. I have a new alternator with internal regulator soon to be installed. The wiring is a disaster and will be corrected soon.

I'll look at the rims and tires and let you know what size they are. They are too wide for my liking and steering is difficult. A local truck yard is locating 16" x5 x6 lug rims and hub caps.

[mr48chev]

There are few things on a vehicle that will make you beat your head against the wall than a previous owner's wiring job.

The wiring on my 48 was old and shot when I bought the truck in 1973 I can imagine what you guys are up against 40 something years later with the same wiring.

I've found that is someone else wired in trailer wires to tow a trailer with that is all too often the problem. On my dualie everyone who towed a trailer with it seemed to have wired in their own trailer plug. To top that off someone wired the tail lights from just behind the plug at the back of the frame with flat yellow 3 stand extension cord. That was real fun to troubleshoot in a parking lot when I was towing my newly bought boat home. That is a job the shop cat and I have to tackle as soon as it warms up and drys out enough to sit on the ground under the truck all day.

[Darthintel]

New alternator installed and working well.
Now to start replacing the wiring.

[dsraven]

nice.
there are so many wiring products on the market these days you should be able to make a really nice harness with all the required circuit protection needed. one of the biggest things is knowing the load, the circuit length and then sizing the wire properly. using relays is also a great idea. auto reset breakers is also not a bad idea as long as you understand that when they "blow" there is a reason that needs to be checked out.
here are a few ideas that may help you

[dsraven]

one more that didn't fit the last post. these circuit breakers work great for larger loads.
for grounds use the same gauge cable as the pos cable because whatever is supposed to go down the pos cable is also supposed to go down the ground cable. also run grounds to the rad support, cab, box etc. personally I always run a ground to the frame, the engine block, the cab, the rad support, the box, the cab etc. if not the rad support and box then I will use a common ground point and run a separate ground wire from all electrical components installed on the rad support or box down to the common ground. don't forget to ground the fuel filler neck as well. bare the metal and use star washers on the ground strap connections for a good conduction, then use some sort of protectant over the connection when all done. use double wall shrink tube over wire connections and loom over the harness supported with quality clamps to keep the harness from drooping and putting strain on connections at each end. a good quality set of wire strippers and crimpers is an asset. tug on each connection when done to ensure the crimp captured properly. try not to twist the wires because when the crimp is done sometimes the overlapping wires can cut each other off and compromise the connection. there is something to be said about the metripack or weatherpack connections, they work well and don't let the elements in. they also look proffessional. they do cost and you need a different crimper to them properly. if using the crimp style connections, with shrink tube, you can buy the uninsulated style for a smaller bulge in the wire harness. offsetting multiple connections in the same area will also help with that. a heat gun works best for the shrink tube. some will use a lighter but that can overheat the tube and make it split. leave enough extra tube at each side of the connection so the glue inside the tube can have a chance to seal the wire properly. some guys will barely cover the connection which can cause issues down the road.
hope that helped somebody, lol.
good luck and have fun.

[Darthintel]

Thank you so much for all the information. I've been using that wire size / amp capacity chart to determine wire gauge as well as the original wiring diagram.
I will be replacing all grounds and also will have a ground bar under the dash. I'll also run ground wire to the grille and the rear of the truck.
I've bought the distribution panel already and pre-wired relays for the head lights and horn. I will use soldered connections and heat shrink tubing. Also all wiring will be covered with some type of sheathing for protection. I have a nice ratcheting crimper. In addition, I bought the solder connections that use a heat gun to melt the solder - thought I would try them.
LED instrument cluster and parking lights work well.

One thing I'm currently doing is I've removed the old voltage regulator from the fire wall, gutted it, and mounting my headlight and horn relays inside it to be mounted back up on the firewall. I'm not done with this, but pictures of the progress.

[dsraven]

nice idea with using the old voltage reg as a hiding place for some other stuff. it will look like it was supposed to out on the firewall. will you be able to weather proof the box as well?
I also use terminal protectant, like dielectric grease, in connections in wet areas. it is non conductive so just use it on the right places or it can actually inhibit the electrical conduction. here is a bit of info on that, in case youcan't get a good sleep at night....

https://www.youtube.com/watch?v=yuKAmaIkA-U

https://www.nyelubricants.com/stuff/...tors_final.pdf


https://support.newgatesimms.com/cho...tor-lubricant/

[Darthintel]

I'm not too concerned about weather proofing the sealed relays. The lid will need to be cut open a little to run the wires out. I have relays under the hood of other vehicles mounted to the fender without any problems. Plus - this truck won't be driven much in the rain.

[dsraven]

it wasn't so much for the relays as it was for the wiring connectors attached on the spade connectors. probably be fine though, like you said.

[_Ogre]

The old generator and ammeter was 30 amp max. Your new alternator may be 100 amp or more. I suggest you bypass all that old wiring and ammeter with a 10 gauge wire straight to the battery

[Darthintel]

The alternator Ive installed is 65A.
The current wiring is 10 Gauge wire going to AMPmeter and battery.
I'm in the process of re-wiring and I'll take your comments into consideration - thanks!

[Darthintel]

3 relays mounted in the voltage regulator housing.