Wiring harness replacement.

[71SSclone]

I'm thinking, since the car is completely apart, why not replace the wiring harness. It's hacked, cut up, and full of bad connections. 

I was looking at a harness from American Autowire. Has any else used them? Is the harness complete, with options already built in (AC, power windows, redefrost, etc)?  Does anyone have any other suggestions? 

I've heard Painless wiring is anything but "painless".  Any other ones that can be reccomended?

Thanks for the help.

 

John

 

[B-Man]

My $0.02 ...

If your car is completely apart, you've got the funds - and you're DEFINITELY going to put it all back together some day - then yeah, why not?!?!?!  It will certainly 'show' better and you will likely have less quirky troubleshooting to do down the road.

https://americanautowire.com/collections/chevrolet/products/classic-update-kit-1970-72-chevy-monte-carlo-510336

My 72 is not taken completely apart, so a new wiring harness would be quite a feat.  Not impossible of course.  I've already put a bunch of hours and $$ trying to figure out all the wiring hacks from the previous owners - some good, some bad.  At some point I will easily spend $1,126 in hours and real dollars, no doubt

[71SSclone]

It’s as far apart as I’m going to take it. She has all new sheet metal, so it is definitely going to go back together!! 

[Scott S.]

I'd think that that's probably as far as you need to go regarding access to replace the wiring.

I've heard good things about American Auto Wiring...... And they can ever be bought with a new fuse box already attached. 

[jft69z]

2 hours ago, 71SSclone said:

I was looking at a harness from American Autowire. Has any else used them? Is the harness complete, with options already built in (AC, power windows, redefrost, etc)?  Does anyone have any other suggestions? 

I use the AAW harnesses. Very good setup, and detailed instructions. Not exactly an easy job, but with careful planning and attention to detail, it'll far exceed the factory harness.

They do not include the A/C or power window harness, but they do offer them separately. I'll typically replace the A/c harness, because they're usually botched up anyways, but if the power window one looks good, I'll re-use it. Maybe replace the rubber boots if they're ripped up (between the cowl and into the door), and clean up any tarnished connectors.

[Jared Richey]

A harness that makes you buy a golden expensive $$ tool to assemble the harness and the tool is not included.  I'm like nahhhh.

I used ready to go factory replacement harnesses in my 59 impala. No issues. I believe American auto wire made them. Updated for the 12 voltage to the coil and altenator. 

Lol

[cbolt]

I did my whole car with kits from M&H Electrical Fabrication. All the harnesses were basically plug and play. All I had to do was remove one plug and plug the new one in, working right down the line on the engine, lighting, dash, console, etc. 

Expensive but well worth it compared to a kit that you have to make as you go. 

[jft69z]

Those factory replacement, plug & play harnesses are ok if your installation is basically stock, or plan very few modifications.  If you plan on adding any type of electronics, modifications, upgrades, or just like to route & hide the wires to your liking, the factory harness will fall short. 

Yeah, you'll find someone that'll say just add extra terminal or auxiliary fuse blocks to accommodate your upgrades, but you might as well have just got a more robust harness to start with in the first place, if you're in the market for a harness anyways. 

Me personally, I like to hide as much stuff as I can, so the ability to terminate the harness ends to my liking is part of the job. It all depends on what type of installation and flexibility you want.

[cbolt]

I have a lot of extras and upgrades, but they were all done after the wiring harnesses were done. When I got the car the wiring left a lot to be desired, so that was one of my first "repairs" after the engine/trans/suspension rebuild. None of the upgrades were particularly difficult from a wiring standpoint, nor did I have to compromise the integrity of the factory wiring too very much. A relay here and a relay there tied in at either the fuse block or battery post. I did find out there are some very convenient wiring connectors nowadays that either add a male post or two to the battery cable connection and any other wiring plug/post instead of the vampire style tie-ins that I had used in the past. Most of the time the hardest part was where to make the ground point, and I solved that with a large gage ground wire that serves as a single point for many of the electrical extras. 

Now if I was building from scratch I would likely use one of the hot rod type kits with the blade style fuse block and enough circuits for all the various stuff but I started from stock and worked one modification at a time. Ill tell ya, having the non-brittle, fresh wires to work with made everything so much easier. I did a kit on my Ford, and it is very nice having the wires all labeled and color coded, plus it was cheaper by far than a factory harness replacement. 

[420ponies]

This is about the only thing I didn't replace on mine. The harness was not touched at all...... until I got in there!!

[cbolt]

Brittle wire is so difficult to work with

[MC-71]

I have changed every wire harness over the years in my 71. I used AA OEM replacements. Perfect fit but no directions. These are really easy to install. The bottom line is our cars are over 50 years old. So are the wires.🔥

[jft69z]

28 minutes ago, MC-71 said:

 I used AA OEM replacements. Perfect fit but no directions. 

I asked M&H about that when I was looking for a vendor to supply my harnesses. Their answer was 'NO' to directions. Being they were only supplying a factory spec harness, you were supposed to use the OEM wiring diagrams.

I imagine the AAW OEM line of harnesses would fall under the same situation, if I had to guess.

[71SSclone]

Thanks for the info.

Do I need a A/C harness if Im installing a complete Vintage Air kit?  I'll have to call and see what is really needed.

I think I'll order the classic update kit, with the added circuits and blade type fuses. I'll ask about other options that are on my Monte. (power seat, power windows, rear defrost, etc)

Thanks for the help.

[1Bad454]

I'm wrapping up my American Auto Wire harness job. The installation instructions are pretty good and their tech support has been great if you have any questions. Here's a link to my first video talking about the kit. 

 

 

[71SSclone]

Great video, Ron. Thanks!  That is the kit I ordered. Since I was installing a Vintage Air system, I didn't need to order an AC harness. Should be shipped in 6-7 weeks.