Harness Wire Splices - Solder or Crimp ?

Tech tips and how to's

Moderators: notoptoy, garth, S Allen

User avatar
Curtis
Site Supporter
Posts: 3260
Joined: Fri Jan 01, 2010 2:49 pm
Location: Des Moines, WA
Model: 1500/1600
Year: Low Windshield-64-67.5

Re: Harness Wire Splices - Solder or Crimp ?

Post by Curtis »

cbez wrote: Sat Feb 20, 2021 12:04 am if you have the right amount of solder in the connection it is not going to stress the wire. you aren't supposed to run it up the wire. like Curtis said you generally shouldn't have much movement there anyway.

electron flow and whatever is just getting too pedantic. I was taught they move on the outside surface of the wire, but it doesn't matter, they are 35 amp cars. any soldered terminal is going to have way more than enough capacity.
That's why I just ignored it and moved on from the discussion about it. Does it turn on or not? Mine turns on and that's what I care about.
66 stroker
67 basket case, the renewal has begun.
User avatar
redroadster
Roadsteraholic
Posts: 1456
Joined: Tue Mar 12, 2013 10:58 am
Location: KCMO
Model: 1500/1600
Year: High Windshield-68-70

Re: Harness Wire Splices - Solder or Crimp ?

Post by redroadster »

Multimeter , ohm tests ....problem solved
We used to wire around with a extra wire and 2 3m quick lock Conn. It works ....the quicker tech makes more
Last edited by redroadster on Sat Feb 20, 2021 9:15 pm, edited 1 time in total.
User avatar
23yrRebuild
Roadster Fanatic-Site Supporter
Posts: 881
Joined: Sat Oct 25, 2003 2:19 pm

Re: Harness Wire Splices - Solder or Crimp ?

Post by 23yrRebuild »

This is some great discussion on the subject of crimping and soldering, but what have people been doing as far as "TAPPING" one or more wires off of, or into another one ? I would assume tapping off another wire would follow the same principles as splicing two wires end to end with a connector, or twisting together and soldering, I'm just curious which way would be more or less efficient and effective. Once I get further into unwrapping and inspecting all of the harnesses, I'll probably consider building new ones. I've counted up to 37 splices / "taps" on the '66 - '67 schematic....YIKES !
Mike - '67 Stroker / 5-Speed
todd lorber
Roadster Fanatic
Posts: 388
Joined: Sun Dec 09, 2007 5:58 pm
Location: Los Angeles

Re: Harness Wire Splices - Solder or Crimp ?

Post by todd lorber »

If you "tap" into a wire, you are scavenging some of the current that should be going to whatever the wire feeds. You'd be better off at least connecting the second wire "upstream" to the nearest terminal. You may still be stealing some current from that circuit but a least you're not taking it out of the wire and opening it to the elements.
User avatar
Mattk
Roadster Nut-Site Supporter
Posts: 550
Joined: Mon Oct 28, 2013 1:49 pm
Location: DFW, TX
Model: 2000
Year: High Windshield-68-70

Re: Harness Wire Splices - Solder or Crimp ?

Post by Mattk »

Use Crimps....quality crimps and crimper. I installed alarms and car audio for years. Plain and simple the solder joints dont allow the wire to flex causing stress fatigue in the wire and eventual failure from bumps and vibration. I repaired many systems where the previous "installer" used solder and as a result some bad things happened (ie fire....which might be bad to some.) I learned more about this when I went back top school for engineering. I have also consulted a friend of mine that was an engineer for Buel before Harley killed the company, and he emphatically directed to splices. I am building my harness from scratch and will be using no solder, except where absolutely necessary and fused.

JMTC

Cheers
MattK
User avatar
redroadster
Roadsteraholic
Posts: 1456
Joined: Tue Mar 12, 2013 10:58 am
Location: KCMO
Model: 1500/1600
Year: High Windshield-68-70

Re: Harness Wire Splices - Solder or Crimp ?

Post by redroadster »

todd lorber wrote: Mon Feb 22, 2021 1:06 pm If you "tap" into a wire, you are scavenging some of the current that should be going to whatever the wire feeds. You'd be better off at least connecting the second wire "upstream" to the nearest terminal. You may still be stealing some current from that circuit but a least you're not taking it out of the wire and opening it to the elements.
The current flows neg to pos on DC with the appliances taking the amps
A improved or redundant ground is always a beneficial mod on something the age of our 311s
User avatar
Curtis
Site Supporter
Posts: 3260
Joined: Fri Jan 01, 2010 2:49 pm
Location: Des Moines, WA
Model: 1500/1600
Year: Low Windshield-64-67.5

Re: Harness Wire Splices - Solder or Crimp ?

Post by Curtis »

So for the most part these harness have worked for 50 years so long as they were not hacked for stuff that shouldn't have been put on them. That is with all kinds of splices. That said, 50 years is a long service life for one of these and even the best condition ones are showing their age.

Solder, no solder, they simply don't flow enough current to really matter from what I have seen. One of the big problems is doing something like putting a 60 amp alternator on wiring and a 30 amp ammeter that was never meant to have one.

I upgrade all the wire in my harnesses and use solder. Haven't had a complaint so far.
66 stroker
67 basket case, the renewal has begun.
User avatar
redroadster
Roadsteraholic
Posts: 1456
Joined: Tue Mar 12, 2013 10:58 am
Location: KCMO
Model: 1500/1600
Year: High Windshield-68-70

Re: Harness Wire Splices - Solder or Crimp ?

Post by redroadster »

Curtis wrote: Mon Feb 22, 2021 4:48 pm So for the most part these harness have worked for 50 years so long as they were not hacked for stuff that shouldn't have been put on them. That is with all kinds of splices. That said, 50 years is a long service life for one of these and even the best condition ones are showing their age.

Solder, no solder, they simply don't flow enough current to really matter from what I have seen. One of the big problems is doing something like putting a 60 amp alternator on wiring and a 30 amp ammeter that was never meant to have one.

I upgrade all the wire in my harnesses and use solder. Haven't had a complaint so far.
A 60 amp vs 30 amp alt ....the 60 amp alt only puts out amps that are drawn from the alt ,like recharging the battery or a appliance in use .plus it's a different designed alt, a square wave design that is able to put out high amps at idle ( for the efi fuel pump) the only downside is it loads the slightly engine more ...back when the old style coil & points voltage regulator was in use putting a higher amp alt could mess with it over charging

Also low/ lite amperage / weak power is a problem for a high or higher resistance circuit more than a high power failure from high resistance open circuit