Need re-wire advice

[TFling]

Going through the wiring on my ‘75 and the PO has completely hacked the harness - lots of splices with electrical tape or bare twisted wires. Insulation and plugs are burned and melted in many locations

I build cables frequently for work so I am confident in wire and cable assembly, soldering, crimping, strain relief, and wire dress

I am considering re-wiring using 18AWG or larger and making my own harness, the interior in completely removed down to bare metal so not much to get in the way, has anyone done this before? Any tips?

I plan on running no radio, heater, ignition chime, courtesy lights, etc. which may make it easier?

Many thanks!

[TX82FIAT]

If you have the patience and will to dissect each circuit stringing new wire into a new bundle then go for it. You will have many advantages. Keep very detailed notes/diagrams in the event you ever want to sell or need to repair something. Usually, when you dig into what prior owner hack jobs were done, it is easier to just replace those sections of wire and connections. The under the hood stuff is easy and sorting out the spaghetti under the dash and re-wrapping in some plastic loom does not take that long. A lot of documentation on brown wire mod, ignition relay, headlight relay, 95 amp alternator, improving grounds.

It's all up to you. If you do a whole new wiring harness share with the folks here. Cost, time to make, installation and results.

[spidernut]

I just about finished rewiring my 71 Fiat that had a hacked and butchered harness. I removed the entire wiring harness and replaced it with a 79 Spider wiring harness that was not a hacked up mess. I don't recommend doing that due to differences in the wiring harnesses. For me, it was fine because I swapped all 79 running gear into the car.

I stripped the interior out of the car entirely and found other bad splices under the carpets, dash and console. Removing the interior made it a much easier prospect. I ended up removing the heater box too so I could get to the wiring for the temperature gauge sensors. With everything removed, it was easier to number each connection; A1, A2, A3, etc., for the instrument cluster; B1, B2, B3, etc. for the lower console, and written names on the connectors for stand-alone parts before removing the entire harness.

I'd recommend taking one section at a time, removing the bundling, inspecting the wiring and connectors, then re-wrapping the section Iif you're going to reuse the harness). It is a lot easier to replace the damaged wiring and connectors than rebuild the entire harness. Usually, the hacks are in the console area and just beneath the dashboard....unless you had my 71. Then everything was a hack job.

The only thing left on my car is the door jam switches, and the license plate lights. Everything else is working great now!

Best of luck!