trailer wiring...black copper at splices...

[DENNIS MIN]

All,

I absolutely abhor fixing trailer wiring, unless I can do a complete replacement with new stuff. Anyways, I did not get my wish and had to repair some existing wiring for a trailer. I did the usual, find the broken wires, clean the grounds, check suspect splices, etc.

As I was going around, a few splices when cut apart, showed wires that were black. I know they won't take solder in that state, and they need replacement, so a crimp butt splice will have to do for now.

I felt bad about doing that kind of repair, so I went to the laundry room and looked through the chemicals I had on hand.

Carb cleaner: no; circuit contact cleaner: no; alcohol: no; gas: no; this went on and on until I had this left-over-from-who-knows-when jug of muriatic acid. I got a mix of baking soda and water for a neutralizer first, then poured a smidgen of acid into a tiny glass jar, the kind you see for jelly samples, and added acid to it. I dipped the stripped ends of the black copper wires into it and the stuf smoked the copper wires clean.

I then neutralized it with the baking soda mixture and made the splices. Not a chemist, but had to see if anything worked.

Time will tell,

D.

 

[DENNIS MIN]

All,

I re-read my post, there were two containers, one with acid, and a separate one with a neutralizer.

D.

 

[BobReeves]

CLR also works, rinse with water.

 

[showcrop]

Yes, the acid will clean the oxidation right off the copper strands so you feel better. The problem is that the acid will also wick up the wire under the insulation so now you have more black copper than you did before.

 

[DENNIS MIN]

showcrop,

Wouldn't the diluted baking soda also wick, then neutralize the acid?

D.

 

[ET]

I have been using the muriatic acid trick for 20 years, solder and heat shrink tubing is the only way to fix trailer wires. I have never had any issues caused by the acid wicking farther up the wires and causing further damage. I never used any neutralizer either.