Questions replacing Main wire harness in 74 midget

[73MidgetLigon]

Hey all i took my midget to the shop to figure out why the battery wouldn't charge, and they found some burned wire harness. So i found a used one on Ebay for a good price and i am thinking of tackling it my self. I'm wondering if anyone has done this if they have any tips or tricks that might help me in my adventure?

 

[Deleted member 8987]

Well, what you have in the car now is a "used" wiring harness.

To go through the work to swap in another "used" harness of literally unknown condition is an effort in futility.

Buy a new harness and do it once.

Dave

 

[SilentUnicorn]

or fix the one you have. I tend to agree with TOC. Why go to the effort and work to put in a used harness? Either buy new or fix what you have. You already know what you have . fixing it makes better sense (and it would most likely be easier) than putting in an unknown.

m

 

[73MidgetLigon]

Well my current harness is quite burned (like a canon fuse) from where the stereo sits to about 2-3 feet into the harness causing quite a bit of collateral damage to the rest of the harness. so im not sure how repairable it is., that's why i went with a used harness. and i went used over new due to lack in budget.

 

[Deleted member 8987]

Fixing it is not hard.
Get a wiring diagram.
Obtain properly colour-coded wires and appropriate sized shrink tubing, a soldering iron and solder.
Cut open the harness in the area of the melt.
Cut it back far enough so you are certain you have seen the last of the melt.

Separate the melted wires from each other.
Cut ONE out, and ONLY one.

Solder and shrink-tube a new one in place.
Cut the NEXT one, and ONLY that one out, and fix it.

Continue until you are done.

Try to make them all about the same length as the original harness so it will loom up with tape okay.

If there are connectors hidden inside, and they are either part of the melt or just there, remove them and solder wires in place of them.

Save all connector ends in a zip-lock baggie and place with your spares, in case you ever do replace the harness and find you need one or two of what you cut out.

MOST manufacturers make harnesses in multiple sections for use in different body styles and to make it easier to install on the factiory floor.

All these in-line connectors do is fail, and generate heat, melting wiring harnesses.

Dave

 

[73MidgetLigon]

Thanks for the help :laugh: I will see if i can take some pictures and show how it went

 

[spritenut]

I gave3 up on buying new harnesses.
I pick up used harnesses at swap meets or Ebay, open them up and fix anything that *may* need fixing, sometimes with wires from a different harness but ALWAYS the correct color wire.
I also add wire for4 what ever goodies I might add in the future.
Fog lamps, stereo, 4 way flashers in Bugeyes, extra gauges, etc.
Usually most smoked harnesses had the red wire for the parking lamp circuit melt, it takes out the main ignition wire since they are right next to each other.
So 2 wires need to be replaced in most harnesses but it ain't rocket science.

 

[Trevor Jessie]

When I made my custom harness for my sprite I used wire from MGB harnesses. They were cheap and I stuck with Lucas colors. Now my car is wired the way I want it with relays for the lights, horn, fan, and the brake lights work WITHOUT the key. Oh, and it is certainly handy NOT to have everything running through only two fuses.

 

[Sarastro]

One thing isn't clear to me--you say you "found" a harness on ebay. Does that mean you've bought it already or just located it and are prepared to bid on it?

If you bought it and now have a second harness, it seems to me that you should compare it to what you have. Then, you can decide whether to replace the whole thing, fix what you have, or use pieces of the ebay harness to fix the existing one. Depends which one is in better condition, damage to the present one notwithstanding. In the final analysis, only you can determine that.

The real problem with wiring isn't damage--you can always fix that. When the wiring gets old, the insulation can get brittle, which is a much greater problem. Then, there isn't much you can do except replace the whole thing. That's really the time to think about complete replacement, not just when it's been damaged.

As for difficulty in replacing the harness, I've never done it, but the idea certainly doesn't scare me. But I'm an experienced electrogeek, comfortable with making electrons do what I want them to. On the other hand, we get a lot of questions here that go "I just replaced my wiring harness, and now the horn beeps when I turn on the lights." and such. So, part of the equation is how comforable you are working on electrical things.

 

[regularman]

Me, I would take the harness loose, unplugging one thing at a time and marking it.
I have found many differences in wiring diagrams and the actual wiring if there has been any work at all done on the car, which most have had some. Take it all loose and unwrap and fix whatever is bad and then use that plastic flex wrap to recover it. It holds the wire good but its easy to get back in there if you need to. Most new wiring harnesses are not going to be a factory fit for the car anyways. I am one of those sick people that actually enjoy doing this kind of thing and working on car electrics in general. Some folks like doing jigsaw puzzles or crosswords, I enjoy the brain teasers of working out electrical problems. They are all simple in the end, once you figure out where the problem is :wink:

 

[Jim_Gruber]

British Wiring can provide all of the proper color coded wires as well. They sell wire by the meter. They advertise in the back of Classic Motorsports. Keep all of the wiring the correct color code.

 

[Trevor Jessie]

I like this covering:

https://www.jegs.com/i/JEGS/555/10658/10002/-1?CT=999

 

[Deleted member 8987]

All I can say is, the wiring is, if original, 36 years old.
Heat, weather, contaminants, the insulation is starting to crack and fail, the copper is corroded in the places it's cracked and corroded....

At some point a new one is going to be required, even if you build from scratch (which I have done).

As long as you have a diagram, and colour codes, and follow said, adding what you want as you go, eliminating all exterraneous connectors, even adding a proper fuse block.

But, to re-install a used harness?

 

[73MidgetLigon]

Hey guys,

So yes i did buy the used harness already i got it off Ebay. i feel fairly comfortable with replacing the harness. I will be thoroughly inspecting the "new" harness and fixing anything i see problems with, as for the people that think im cray to use a used harness i have taken your comment to hart and will keep my original harness and use it to build my own new one for later use. Thanks everyone for the help there are bits and pieces i will use from everybody's help :laugh:

 

[73MidgetLigon]

Ok well i ended up using the harness that i got from ebay to steal wire from to rebuild my old one its all pretty and clean now everything electrical works great, except my original problem. Which is that my battery will not charge, I jump started the car let it charge off the truck for a few and then drove it around and to no avail it started to run like crap because the battery was discharging. The battery is new, the alternator tests fine, Any ideas as to where to go next what to test? HELP!

 

[JPSmit]

is the bulb working? seems to me it is part of the charging system

 

[73MidgetLigon]

What bulb?

 

[Deleted member 8987]

The "IGN" bulb in the instruments......

The one that should come on when you turn the key on, and goes off once the car starts.

 

[jlaird]

TOC is correct, bulb has to work.

Ask the guys at the 50th at Lake of the Ozarks. Hehe, there was a test.

 

[tweety]

Is there a charge light in the dash? Is the bulb good? I seem to recall that if the bulb is bad, the batt will not charge.