New wiring harness worth it?

[muddpile]

I was looking at my old 72 today, getting ready for the teardown, and I noticed that the 30 year old wiring looks pretty bad. It's not bare or cracked that I know of, just looped all over the place, spliced, etc. Since I am doing a frame off anyways (or the better part of one for sure) should I replace the whole setup? My truck is low options and will stay that way. It has power steering, manual brakes, column shifted auto, no air, extra gauges but no tach, and the engine and HEI out of an early 80s suburban. Is it worth it to get a new harness, or should I just try and sort the old one out and tidy it up a bit?

Also, how hard is a new harness install, and what one should I buy? Thanks!

[BobbyK]

depends on your finaces.
Wireing is the blood of your truck,without it you'll have plenty of problems.

I personnally would bite the bullet and buy a new harness.
30 year old wiring is a fire hazzard as well.

[GreyHoundSteve]

I decided to go with a new painles harness and im glad i did. The wiring on my truck was in about the same condition as you described yours. The original wires were in decent shape but alot of them had been spliced by the po's and i was getting shorts so i decided to pull it since i was doing a frame off. The new harness was an easy install and looks great. It also has alot of updated provisions and while you may not plan to add any of these options now you might change your mind later and even if you dont youll have plenty of extra space fo anything else you might want to add in the future. If i ever do another one of these trucks the old harness will be the first thing to go again.

[ChevLoRay]

If you have to ask, then the answer is YES.

I have replace all my underhood wiring, except for the A/C specific harness, since I am not using the A/C at the time...pending the paint job on my truck.

Go to www.wiringharness.com for the website for M&H Fabrication. They make reproduction harnesses and can modify them for 1-wire alternators or HEI distributors. The color code is as new, and all connectors, brackets and covers are already in-place.

I liked dealing with them, better than someone like LMC. LMC is just a jobber and knows very little about what you are ordering. M&H builds them and you can call them and ask all kinds of questions.

[gabet40]

ya especially if ur already doin a frame off. gonn have to tuck n route all the wires anyway, might as well make em nice new ones. ive heard those r pretty easy to install anyway

[tkeduk8r]

I chose to go with a new harness for an engine swap I did in our 68 skylark ragtop, and it was the best 150 bucks ive spent for restoration anything... I bought through year one, but it was an M&H as previously discussed... I tore alll the old spliced, broken, rotten harness out and routed the new one with the instructions and factory chassis service manual and it rocks.. lights are brighter, more powerful spark, better fuel milage and its all correct under the hood now... highly recommended.. im not even thinking about using the stock harness on my 70 resto!!! hope that helps..
--Mike

[4LUG39]

I used an E-Z wiring I bought off E-Bay on my 39, It worked great. This is after wiring my 54 on my own, That was not smart. Save time, money and piece of mind.

[BOSS]

I chose to just fiz the wiring in my 4x4 and if i had it to do over again i WOULDNT!!!!! Now i am haveing problems everytime i turn around and still dont have it all fixed yet.Save yourself some time and heartache and get a new harness.I know i wish i did.

[mac]

I put a RON FRANCIS 12 circuit in my '67 and it was the best money I've spent. I welded up all the pass thrus to the engine compartment and ran everything south and hidden. Sure cleans up under the hood. Behind the dash can be loomed up as you wish. I put in a VDO instrument set and bought a gage harness from them too. The extra $60 makes it all pretty and professional looking and if anything ever needs to get redone, its slick and easy. The one thing it didn't give me was a new wiper harness. I fab'd one using the original plugs and wire colors.

[Blue_71]

i redid every wiring harness on my 69.... completly rebuilt each one from may-as-well-been scrap, to working stock harnesses... had to rewire in the radio and speakers too... it was scary what all i found in there, but everything works now except for one light that i didnt rewire, and one that has a blown bulb

[muddpile]

Well, here is what I've got. I've made myself a comprehensive list:
(1972 chevrolet LWB)
-Headlights (will be upgrading to better)
-Taillights (will be going with ECE LED's)
-Marker lights
-Instrument cluster
-AM radio (won't need to be hooked up, just there for looks)
-Wipers
-Interior Light
-Heater and no air
-CD deck (will be installed in glove box)
-HEI (already installed and working, but like I say, questionable install all around)

I may have missed some stuff, but that looks to be about it. What harness should I get? I have always heard good things about Painless. Are they worth doing? Also, Are there terminals on these new harnesses, or how would I go about attaching the new wires to the old parts such as gauges, lights, etc? Thanks for the help so far! It looks like this is a very worthwhile thing to do. Another bonus I noticed is that the new harness comes with a fuse block for the nicer plastic fuses.

[4x4Poet]

I've seen a Ron Francis wiring harness. Each wire on it has what the wire goes to written on its respective casing every 6 inches or so all the way to the end connector/terminus, so you always know what wire/circuit you're dealing with when you're away from the fuse block originating point. Good feature. I would probably still use an M&H harness myself since it fits like oem and because I don't need much special. Maybe things will change with my K20 rebuild.