Car had 10 miles on the clock when I first test drove it. So...I'm not really sure what to think of it. Not going to worry too much about it...since there isn't anything I can do about it.
7
Wire taps?
- Thread starter Chogokin
- Start date
Car had 10 miles on the clock when I first test drove it. So...I'm not really sure what to think of it. Not going to worry too much about it...since there isn't anything I can do about it.
snobrdrdan
former GTI owner
- Location
- Southeast Michigan
I wouldn't be concerned about it either....I was just saying because you asked about it
Bäsemödel
Go Kart Champion
- Location
- Lancaster PA
i have a positap on the AFR wire for the JB4... havent had an issue...
GTI Jake
Autocross Champion
- Location
- Charlotte, NC
It’s not something that happens overnight. Ask any professional mechanic, engineer, etc and you’ll get the same response I gave
Wires are very vulnerable to vibration and corrosion. Cutting the shielding and using a knife edge against bare wire in something constantly vibrating (especially in the engine compartment) will end up with one of two results. Cutting the wire over time or “green death” corrosion extending both directions from the connector.
I wouldn’t lose sleep over it since none of you guys will probably keep these cars the 10-20 years it’ll take for this to happen, but I’d suggest using a better method in the future
bbjwvr6
Passed Driver's Ed
- Location
- Rhode Island, USA
I agree with the assessment of taps, however one issue I’ve had with soldering wire splices with smaller gauge stranded wire is that the soldered section becomes rigid and develops a stress riser where the solder stops at each side. You can layer heat shrink insulation to provide stress relief, but if you’re not extremely careful, these wires will break at the solder joint with repeated flexing. Not good right next to a harness connector.
In some cases, I prefer cutting the wire being tapped and using Posi-lock or Posi-tite connections with a good screw terminal at each cut end. But not Posi-taps.
southpawboston
Drag Racing Champion
- Location
- Somerville, MA
You are correct about stress risers and soldering. That's one of the reasons terminals are not typically ever soldered. One crimp is for the metal contact bonding, and the other crimp, of the jacketing, is for strain relief.
In an automotive application where a soldered splice junction will be stationary and not under stress, this is not an issue at all. Normal road vibrations will not affect it.
bbjwvr6
Passed Driver's Ed
- Location
- Rhode Island, USA
Yes, but some junctions in an automobile can come under stress. Anything located near a harness connector or in a harness that may eventually be pulled on to work on other wires can be subjected to strain enough to break the wire at the solder joint.
People should think about whether the joint they are making will ever be subjected to pulling stresses and decide whether a soldered joint, even with strain relief, is the best choice for that application.
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Cuzoe
Autocross Champion
- Location
- Los Angeles
No love for proper crimps? I'm talking about properly sized splices with the right crimper of course. Don't all of the wires in the our cars end in crimped terminals anyway?
I'm a fan of environmental splices myself, coming from an aircraft electrician background, but if you don't have access to them it's not worth the investment if you won't be doing regular wire work. My current job will sell employees the splices at their cost so I'm lucky there, and I bought the crimper many years ago.
I suspect most people considering wire taps don't have the tools and/or experience to make good reliable solder joints. I would recommend solder sleeves for these folks. Minimizes risk of solder wicking into the wire creating brittleness, environmentally sealed (not important for interior work), visible connection, and the sleeve provides stress relief (could add heat shrink over top if worried). They are also inexpensive and only require a heat gun and wire strippers.
Decent link here (up to the electrical tape part, which I would not recommend): https://conceptzperformance.com/blog/solder-sleeves-and-injector-harnesses/
I'm a fan of environmental splices myself, coming from an aircraft electrician background, but if you don't have access to them it's not worth the investment if you won't be doing regular wire work. My current job will sell employees the splices at their cost so I'm lucky there, and I bought the crimper many years ago.
I suspect most people considering wire taps don't have the tools and/or experience to make good reliable solder joints. I would recommend solder sleeves for these folks. Minimizes risk of solder wicking into the wire creating brittleness, environmentally sealed (not important for interior work), visible connection, and the sleeve provides stress relief (could add heat shrink over top if worried). They are also inexpensive and only require a heat gun and wire strippers.
Decent link here (up to the electrical tape part, which I would not recommend): https://conceptzperformance.com/blog/solder-sleeves-and-injector-harnesses/
southpawboston
Drag Racing Champion
- Location
- Somerville, MA
Those are neat. I've never used them. How does a heat gun get hot enough to melt solder? Is it a special low melt-point solder? Reminds me a little of the copper plumbing pipe fittings you get with the solder built-in to them. Just assemble and apply torch.
I have always twisted my wires to make straight unions, then soldered and applied the appropriate diameter shrink tubing.
Cuzoe
Autocross Champion
- Location
- Los Angeles
I assume it is a low melt point solder. We use them at work when building harnesses to ground the shield of twisted pair wiring. We call the ones we use "bottle rockets" because they have a ground wire sticking out of them already. Your standard Home Depot heat gun on the first setting will flow this solder though.
I have seen some try a butane heat gun (in tight spaces) and it's much too hot, ends up burning the sleeve.
I use the same method you do if I don't have my crimpers and/or splices. With some practice it's solid and reliable. The solder sleeves are simple though, combines the soldering and heat shrinking into one step, I like them alot.
These are what we use it work, soldered to the shield of twisted pair/triplet wire: http://www.aircraftspruce.com/catalog/elpages/soldersleeve11-12363.php
I have seen some try a butane heat gun (in tight spaces) and it's much too hot, ends up burning the sleeve.
I use the same method you do if I don't have my crimpers and/or splices. With some practice it's solid and reliable. The solder sleeves are simple though, combines the soldering and heat shrinking into one step, I like them alot.
These are what we use it work, soldered to the shield of twisted pair/triplet wire: http://www.aircraftspruce.com/catalog/elpages/soldersleeve11-12363.php
GTI Jake
Autocross Champion
- Location
- Charlotte, NC
At work I very rarely repair anything and never use any splices, I’ll just build new harness or order one if it’s something serious (spent $28,000 on a harness recently lol)
I’m not sure where crimp connections would help the OP, he was teeing off an existing circuit (unnecessarily though since all he needed was keyed power)
Before and after. Damn harness was about 20’ long
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Cuzoe
Autocross Champion
- Location
- Los Angeles
I hate building harnesses, almost as much as I hate installing harnesses, haha. I'm in corporate/private aviation so replacing harnesses is practically never an option. No customer is going to let us spend 150hrs removing their interior/galley to replace a harness when we could just repair the wiring, not that we as a company would be interested. These are mostly built to order aircraft so (for the systems I work on) there typically aren't any harnesses to order even if we wanted to, just engineering prints.
We do some installations (high speed internet, cabin entertainment mods, general system upgrades) where a harness can be built but even then our pre-fab harnesses are cut/terminated to fit once installed. We can't be positive our planned part locations will work until we get an aircraft torn apart.
I see a filter cover and fluid lines in your picture. As an avionics guy I'm trying to stay away from every bit of that.
For the OP, no issue with using a splice as a wire tie to "tee" off of an existing wire. Aircraft OEMs do so in their factory installed wiring regularly. I guess this is all academic now unless the OP runs into issues in the future with the T-Taps. My issue with the T-Taps (outside of those mentioned here) is that I want to verify my connections, T-Taps keep secrets, haha.
We do some installations (high speed internet, cabin entertainment mods, general system upgrades) where a harness can be built but even then our pre-fab harnesses are cut/terminated to fit once installed. We can't be positive our planned part locations will work until we get an aircraft torn apart.
I see a filter cover and fluid lines in your picture. As an avionics guy I'm trying to stay away from every bit of that.
For the OP, no issue with using a splice as a wire tie to "tee" off of an existing wire. Aircraft OEMs do so in their factory installed wiring regularly. I guess this is all academic now unless the OP runs into issues in the future with the T-Taps. My issue with the T-Taps (outside of those mentioned here) is that I want to verify my connections, T-Taps keep secrets, haha.
GTI Jake
Autocross Champion
- Location
- Charlotte, NC
Yeah I’m line maintenance for a major airline so money spent on parts is no big deal for them, but I agree building or re running harness is no fun lol. That was on a CFM 56 and more recently I swapped the whole APU harness (both on A320)
The playing in fluids (fuel, skydrol, oil) part can get old, but troubleshooting is my favorite part of the job so you find it you fix it applies and gets me into a variety of stuff you’d never volunteer for haha
Hopefully someone in addition to the OP can benefit from the electrical knowledge in this thread, next time I have a project that could be informational maybe I’ll do a write up. Not that I’m the most experienced, but once the ball is rolling more knowledge is always added by the forum
The playing in fluids (fuel, skydrol, oil) part can get old, but troubleshooting is my favorite part of the job so you find it you fix it applies and gets me into a variety of stuff you’d never volunteer for haha
Hopefully someone in addition to the OP can benefit from the electrical knowledge in this thread, next time I have a project that could be informational maybe I’ll do a write up. Not that I’m the most experienced, but once the ball is rolling more knowledge is always added by the forum