Try to use old harness or buy new?

[tdog]

Purchased a 69 Bronco it sat in a field where for 20 years. Mice, roaches and spiders called it their home. When I got the rig home I threw a batt in it the starter worked and I pulled the light switch and one taillight worked. Then I stared fixing rust. Now the Dash is out and the harness is still in the truck. I am on a tight budget and would like to try to use the old harness. Do I dare? It seems like Everything I read people replace the harness. I have delt with classic mustangs and they seem to not have problems with the wiring ? I have not found one chew mark on the harness from the mice. Any advise?

Thanks

 

[lowbush]

I went with the EZ-Wire harness it's like 140 bucks and man I am glad I did. So much easier than trying to figure out 40 year old wires that where never labeled.

 

[casadejohnson]

I have reused the original harness in all 3 of mine. I would make a judgment call based on its condition. If the previous owners hacked it up and it has miles of extra wire and electrical tape maybe you need a new harness but if it looks relatively unmolested and not chewed up by mice I would not have an issue with using the original harness.

 

[TN1776]

As others said, its a judgement call. I replaced mine because it was a little too far gone for me to feel comfortable with. Lots of cuts/splices and an alarm that looked to be installed by a kindergartener made that decision for me. The wires that were not "molested" were still in good shape, there were just too many problems for me to want to correct. The EZ-Wire harness was my choice as well - its okay, just not very plug and play, and the fuse block is kind of a joke - the fuse sockets are not marked, only the cover that goes over the block is - and it fits on two ways so its kind of useless.

 

[Airmapper]

I went with the EZ-Wire harness it's like 140 bucks and man I am glad I did. So much easier than trying to figure out 40 year old wires that where never labeled.

I think if I had it to do over again I'd do like lowbush. My wiring wasn't bad, but the comfort of having all new wire and not relying on old connectors that could go out at any time, it would be worth it.

I pulled mine and spent a few months overall patching it, modifying it to work with mods and improve the setup. With modern tech and wiring, you can vastly improve the systems, most are inadequate and poorly routed.

For example I re-routed power to high drain devices, like the headlights and horn, through a modern power distribution box out of a late model Ford. Old wire no longer had to carry load, only switch relays. I now have a electrical system that works very well, but now that I have a better understanding of it, I would have further simplified it, and went ahead with a new base harness so I won't have to fix connectors and old wire later.

Either way you go your going to spend some money. I have a few hundred into my wiring just fixing the old harness, but I also had to tool up with supplies and equipment, and I don't regret the money spent as it was darn near a crash course in automotive electrical systems. I'm a lot more comfortable with wiring than I was, and you should see me soldier.

So personally, I'd go for the cheaper base harness so you can get most of the wiring as new wire and connectors, and then modify as needed, and that can even be put off once the base harness is in good shape.

 

[Broncobowsher]

My last bronco had a molested harness. I spent a weekend and got it back working just fine. Years later I started adding a lot more electrical (EFI and stuff) that finally got me around to doing a full rewire.

But as mentioned, it is a judgment call. Think of it this way, try fixing what you have. If it really is so screwed up you wiill know after a day of messing with it.

 

[707Bronk]

Its a judgement call for sure, but after a couple years of fixing, repairing and rewiring several sections that had been hacked and spliced by the PO, I finally went ahead and used the EZ wire kit. Now I have peace of mind not letting the smoke out in the middle of nowhere. I only regret not doing it right off the bat, but back then it was my daily driver in college and beer was way more important.

Anyone considering the EZ kit should know it can be as good as a painless harness or as bad as the original harness. The layout and connectors and terminations you choose are what makes the difference.

If you are a novice that wants to get back on the trail asap, the EZ wire kit may not be for you. If you a novice that wants to learn about wiring and willing to have patience then go for it. Anyone with moderate experience with the EZ wire kit will have zero problems.

 

[tdog]

Thanks everybody. I am a couple months away from making that choice. Some of Your advice have given me some confidence that the original harness is usable if I don't find bad spots or hacked wires.

Thank you

 

[72_EB]

Are the old wires brittle? Are the fusible links burned up? Is your fuse panel rusted out? The red, covered wire under the dash by your speedo is your resistor wire, is that burned up? If you answered "no" to all of these, you can probably rebuild it. The engine bay, alternator, and chassis harness to the taillights are usually the worst, along with the fusible links. Under dash are (usually) only hacked up a little for radios and stuff. You can do it. Good luck.

 

[DirtDonk]

72_EB's first comment was the kicker in the last one I helped with.
It was a '77 going to EFI and it was hoped to keep the relatively unmolested harness intact. However, after the first couple of wires actually broke then insulation when bent, deciding to go all new was easy.

On the flip side of that coin, even though I'm definitely going all new on my own '71, the original harness that's coming out is really in outstanding shape for a 41 year old bunch of wires.
The original owner cut and spliced a few things, but I fixed those years ago. Other than that, the harness would be a good candidate to reuse if I wanted to save money.

So as said, give it a real close once-over (maybe twice, just in case) when you're ready, and see which way you want to go.
If you stay with original though, don't hesitate to install new connectors or light sockets where needed, and please, by all means add ground wires to anything that looks like it needs it!
Mostly the dash and core support sections.

Paul