Secret sauce to soften up plastic coating on old wiring ?

[californiamilleghia]

Hi ,  I am helping  fix a 1968 912 Porsche  and would like to use the original wiring harness , which is in good shape .....EXCEPT

 

The plastic covering is hard in a few places on many of the wires , .

 

Is there a "secret sauce" that will soften the plastic covering , 

 

This would be the individual wires , not the black tube that goes around the bundle.

 

Or other ideas , maybe a steamer or ?????

 

Thanks for your ideas

[8E45E]

Is the insulation PVC or similar?  Try coconut oil to soften it.

 

Craig

[rocketraider]

Lacquer thinner will clean off grime and bring back the color. Depending on the insulation's composition it sometimes softens it too.

 

Steaming it is an interesting idea.

[californiamilleghia]

I was thinking steaming like you do with wrinkled shirts  , or maybe a hair dryer, 

 

I am assuming that the copper wire did not get hard, 

 

Hopefully this discussion will help others in the future .....

[Xander Wildeisen]

You can buy shrink tube in all colors and lengths. Straighten out your bad wires, side the colored tube over them. And shrink it down. https://buyheatshrink.com/

[Frank DuVal]

Adding heat shrink will not make the wire more bendable. It is the insulation that is hard, not the stranded copper.

[yachtflame]

   You’re talking about a 55 yr old wire harness. You want to do something that will “soften” the plastic for what purpose? If it’s that brittle, the copper inside is most likely starting to corrode also and the wire ends are fraying. This just seems like a formula for a roasted marshmallows party!
 That said, I googled “wire harness for 1968 Porsche” and got a shock! The wire harness on my 1949 Jaguar MK V saloon was only about $1500. The Porsche seems to be double that. I get the double take but at this point, you have a 55 year old fire hazard which could turn your prized possession and maybe your garage into a charred nightmare.

 My advice…save up and do it right!

[bryankazmer]

Two things have happened to the jacket material, which is likely PVC compound.  The plasticizer is largely gone and the PVC resin itself is degraded. Adding replacement plasticizer(like coconut oil) will not really replace the original but may soften it a bit by swelling the compound. It will not address the  PVC degradation. You need new wiring. 

[Mark Wetherbee]

I agree with Yachtflame, you want to risk an electrical fire on an expensive car just to save money on doing it right???

 

Buy a new harness and put the worries to rest.

[bryankazmer]

In disposing of the old wiring, be aware that the jacket has a couple % of lead compound as a stabilizer

[Frank DuVal]

1 hour ago, bryankazmer said:

In disposing of the old wiring, be aware that the jacket has a couple % of lead compound as a stabilizer

And??? Your trash hauling service looks that close?  Seems like regular trash to me. Or take it to the "metals" scrap yard and get a few cents. Currently 46 cents per pound for small insulated wire around here.

 

11 hours ago, yachtflame said:

If it’s that brittle, the copper inside is most likely starting to corrode also and the wire ends are fraying.

Unless next to the battery, like the corroding/turning green of the battery cables, I have not seen the copper corrode to where it is not functioning. I do see the copper get a black color (maybe from the plasticizers?)  that is very hard to clean in order to solder to it. All Corvairs are over 50 years old, and except for connections being dirty, most of the harnesses are just fine. The harnesses get replaced because of previous owner/fiddler modifications and dirty (corroded) connectors. Now, the cloth covered harnesses of the 50s and earlier, that rubber insulation under the cloth is just falling apart, replace those fire hazards! 🕷️ 🕸️

[Restorer32]

Be happy you do not have a 1958 Cadillac Brougham. We will be repairing one that suffered an engine fire that destroyed the dash and associated wiring. New harness?  $ 12,000.  Don't take a chance. Replace your harness.

[Jack Bennett]

I’m missing something here. It appears the wiring harness is either out, or so exposed,  removal is the next easiest step. Replacement parts for a 1969 912 Porsche can’t be cheap, and, most certainly, the budget allotted to restore the car to operation must be more than a few dollars. It seems obvious, since the wiring harness will become inaccessible once the interior of the car is closed up by upholstery and panels, that replacement of the harness is a no brainer. 

[60FlatTop]

When appraising A Porsche a sauced wiring harness would be noted as "Porsche- needs wiring harness". Could reflect on the value.