Carpokes

Hi all, apologies if this as been asked/answered before but I'm trying to solder some broken wires in the door harness. However, for some reason, my solder isn't adhering to the original wire. It's an '86 951 so I'm wondering if there's either some sort of coating on the wire or just age/oxidation that I need to clean off before the soldering process. I think I'll try brushing the ends with alcohol and see if that makes a difference. Any other suggestions/recommendations would be greatly appreciated.
Thanks, John

Flux will help but for those kinds of repairs I like these guys: https://www.amazon.com/Connectors-Kit-W ... 81Z9L?th=1

There's all kinds of options, those are just an example of what I'm talking about.

Good luck

Acetone and scotch bright on the bare wires. Then you should be good to go with just flux core.
Then heat shrink. I recommend the style with glue inside. Good as new

Also be sure to tin the soldering iron and try to get the solder melting on the iron first if needed. Much easier to get the heat into the wires with molten solder, I assume because the heat flows in and around the strands, whereas the iron just touches whatever it touches...

PSU_Crash wrote: Wed Sep 10, 2025 4:35 pm Acetone and scotch bright on the bare wires. Then you should be good to go with just flux core.
Then heat shrink. I recommend the style with glue inside. Good as new

Thanks for the input. I tried alcohol but it didn't help. Acetone sound like a better alternative that I'll try in the next day or so. Thanks much!

Zirconocene wrote: Wed Sep 10, 2025 4:03 pm Flux will help but for those kinds of repairs I like these guys: https://www.amazon.com/Connectors-Kit-W ... 81Z9L?th=1

There's all kinds of options, those are just an example of what I'm talking about.

Good luck

Yeah, I tried using flux but still didn't stick. I looked at connectors like the ones you suggested and will likely go that route. I'm just hoping that whatever coating on the wires won't inhibit a good connection. Thanks much!

Also make sure to have good solid contact with the wires. If you try to solder with a wire hanging in mid-air, it's hard to transfer a lot of heat from the iron to the wire. I have a little block of wood I use in those situations so you can press the iron against the wire with decent force...

Tom wrote: Wed Sep 10, 2025 4:45 pm Also be sure to tin the soldering iron and try to get the solder melting on the iron first if needed. Much easier to get the heat into the wires with molten solder, I assume because the heat flows in and around the strands, whereas the iron just touches whatever it touches...

Yeah, I made sure the soldering iron was "tinned", even to the point where there was a ball of solder on it as it contacted the wires. Unfortunately, the "ball of solder" stayed on the solder iron and not on the wires. Flux paste didn't help either! Whatever is on the wires is preventing it from "sticking". Hopefully, acetone will clean that off so I can get the solder to adhere to the wires.
Thanks much!

It's all about heat really. How hot is your soldering iron? You generally want to heat the wire up and melt the solder into it, rather than trying to get melted solder to flow into the wire.

Tom wrote: Wed Sep 10, 2025 6:22 pm Also make sure to have good solid contact with the wires. If you try to solder with a wire hanging in mid-air, it's hard to transfer a lot of heat from the iron to the wire. I have a little block of wood I use in those situations so you can press the iron against the wire with decent force...

I've definitely made sure that I've got good contact. I have the wire held in a little vise so I can have the iron in good contact. I even tried to heat the wire with a small propane torch but the solder still would just "roll off" the wires. Hopefully acetone will get rid of whatever is on the wires so the solder will stick to it. Otherwise, I'll just use the crimp connectors and hope that whatever is on the wires doesn't inhibit an electrical connection. Thanks much!