[Scott MH]

Originally Posted by keithb

you say you worked on 100's of classic cars. how many of them had a wire fire. I do say replace them if they are all cut up and messed with.

One, it was a 66 ford mustang. Car was brought to me a charred mess. Fire started behind the dash burned the car then took out the garage with it. Thankfully the garage was not attached to the customers house. He paid top dollar at a auction and assumed it was a good car. $45,000 worth of damages plus whatever his garage cost him.

[Scott MH]

Originally Posted by RichG

If you replace the harness go with M&H or American Auto Wire. STAY AWAY from PAINLESS! They are nicknamed Pain in the A$$ for a reason! I'm sure someone will chime in with how great painless is but do the research. M&H and AAW are head and shoulders above!

I've installed painless, m&h and aaw kits. You get what you pay for. Painless is a descent kit for the money, it's also the cheapest. Wire size is sufficient and it's easy to install. I haven't used a crimp connect in years everything is solder and shrink wrap. However even the expensive kits need to be reworked and altered to work

[Robinls5]

I built a SS 454-70 Chevelle Sta. Wgn. in 2002. The under-dash and under hood harness were from my one owner 70 SS 454 El Camino. Cleaned every connector,did some minor repairs, Dielectric grease on EVERY connection.
The 42 year old used SS under dash and under hood harness have been just fine since 2002 or 10 years. It was not chopped up. If is NOT CUT UP, Clean it, Inspect for broken loose wires, And reinstall.
I use dielectric grease on every connection. This may be right or wrong, I do not know????? So far the FORTY TWO year old harness (under dash & under hood) are still working. No fires yet.
Bob

[Philip]

Originally Posted by Scott MH

One, it was a 66 ford mustang. Car was brought to me a charred mess. Fire started behind the dash burned the car then took out the garage with it. Thankfully the garage was not attached to the customers house. He paid top dollar at a auction and assumed it was a good car. $45,000 worth of damages plus whatever his garage cost him.

I saw a 72 Chevelle go up in flames, but it was from added components not the GM wiring. Inspection is the key and it is easy to see a hack job, the hacks do not try and make it look pretty. Biggest tip off are extra wires running to the battery.

[Camaro_fever68]

If electric fans, high output alternators, electric fuel pumps, big stereos, etc are added to a car and not wired right, I could see the factory harness not holding up. They weren't built for that. Other than that the factory harness is great and will work with anything added if the new add ons are wired correct.

[Philip]

When adding all of the high amp draw accessories I use a separate wiring system. A small fuse panel is added for the additional circuits, protected with fusible links between it and the battery. Wires need to be of proper size and loomed to protect them.
As said it is the hack jobs that cause problems. The worst hack job I have seen is the 57 Bel Air I am now rewiring. The owner paid a shop to install an AAW harness. None of the connections were made properly. There many places of wires just twisted together and covered with black tape. Hacks can mess up anything, in this case it was all hidden under black tape, but all those fat spots in the harness were a dead give away that something was not quite right.

Here is a gauge cluster I wired using factory wire gauge size and colors for each circuit, soldered connections and a weather pack connector. It takes some time to do it correctly but it should never need to be redone.



A schematic was also created in case trouble shooting was necessary in the future.

[Grumpys68Chevelle]

Ok well I went by the shop to look at the wiring of the Chevelle and saw the clips in the fuse block that hold the fuses in are in fact rusted. So looks like I am going to have to replace it. So if I got with and aftermarket wiring system what are the recommendations? I have used Painless in my Mustang and yes it was a pain in the A$$. But what if I replace the wiring with the same style? Like if they remake the original style. So replacing is for sure but now which harness?

[Grumpys68Chevelle]

SoCal here in Arizona has a Haywire Universal kit, anyone heard of it and what do you think of it?

[Philip]

The clips can be cleaned but if you go after market American Auto Wire would be my recommendation. Easy to install, uses OEM colors and connectors all the circuits are well marked.

[Grumpys68Chevelle]

I would like to go original but those clips were my only worry. How do you clean them?

[Philip]

Usually it is just surface rust. If it has pitted it would be best to replace, either the panel if you can find a good one or with a new harness.
Naval Jelly will remove it, maybe a flux brush could be used to apply it and make sure it is all rinsed off.

[Grumpys68Chevelle]

Didnt look like pitting just surface rust.

[lrdvdr41]

Use Brasso to clean them. Home Depot carries it.

[1971ss454Elco]

I agree on both sides of the table...

As we were restoring our 71SS454 Elco we had the dash as well as everything else out. The original SS dash housing was so butchered with holes and cracks everywhere that we purchased a repro dash housing(I know, I know). As I was cleaning the original dash harness, although not cut, I noticed hard brittle wires everywhere especially near the fuse block. I purchsed a high quality dash harness from M&H as well as a front lamp and engine harness but left the body and all other harness alone and intact as they were not worn or butchered. The M&H kit was as close to "plug and play" as you are going to get IMO and installed perfectly utilizing correct GM style connectors and required no modifications. The only mild gripe I have with M&H is they dont label each wire for the component it goes to as their competitors do(then again M&H prides themselves on OEM resto quility and GM didnt label theirs either)

Caveat 71-72 connectors and I would assume ALL harnesses nade by them used were from the latest GM revision for that model year and optioned harness so they may not be exact to what you have as these years were pivital. Since yours is a 68 model year I would assume it would probably be a fairly straight forward R&R as well.

We probably could have left dash harness alone but dash was out anyway and all new wiring from dash forward makes me able to sleep at night as well as feeling more at ease when taking car out for long drives.

Marc S

[Grumpys68Chevelle]

Well the wiring is still in the car, that will be my next project when it gets back from getting metal work done. I almost want to just replace everything to have a calm mind about it but if there is nothing wrong with the original stuff, why worry.