I rewired my Jeep to use an HEI ignition system rather than the factory setup with separate coil/ignition module, etc and I have ended up with some looped wires. In two cases, three wires going into one. Space is limited and I am trying to make it look similar to factory. What I've done for the time being is twist my three wires together and crimp them down into a **** connector with the single wire coming out the other side. Then covered it with heat shrink. I'd rather not do this long term and I would rather not use a bus bar since that will just complicate things. Is there another option? I've seen other places on the jeep where they uses a crimping sleeve to join for wires together. I really like weather pack style connectors but typically they are one-in-one-out style.
Car wiring - three wires into one?
- Thread starter Mavawreck
- Start date
Alchymist
Well-known member
Depending on wire routing, if I have 3 into 1, I usually put 2 on one side of the **** splice, and 2 on the other. Easier than 3 on 1 side, looks neater, easier to heat shrink. Electrons won't know the difference. 
Depending on wire routing, if I have 3 into 1, I usually put 2 on one side of the **** splice, and 2 on the other. Easier than 3 on 1 side, looks neater, easier to heat shrink. Electrons won't know the difference.
Thanks for the suggesting, it seems like I could actually loop the third wire under, heat shrink the whole thing, and no one would probably be the wiser. I like that idea.
evildky
Well-known member
everyone always likes to solder and heatshrink but in most OE applications they are simply crimped and wrapped in tape, sometimes they have additional sealant goo on the joint but it's always a crimp connection, the joints are always burried deep in the harness os there is no risk of pulling and moisture is unlikely but I've seen some become an issue after 30 odd years
98TJ
Well-known member
I'd solder and (since it's on a Jeep) use marine grade heat shrink. It not only shrinks, but seals the joint due to it's adhesive lining.
Taping will work for short term, but you have to use a high quality tape if you expect it to last for a decent length of time. The cheap tape will peel.
Taping will work for short term, but you have to use a high quality tape if you expect it to last for a decent length of time. The cheap tape will peel.
Drew_flux
Well-known member
I would do it 2 ways. A) cheap way one feed wire, with the other two spliced off it.(heat shrinked). B) if space allows buy a "junction connector" these have a small bussbar built into the back of the connector. they come in 2,4,6,8 way connections.
Lotek
Well-known member
Soldering can give you a hard spot, if you don't support both ends well, vibration can break the wires, causing weird, hard to trace intermittent faults. In the field, a **** connector and heatshrink is usually the best way to go.
Agreed, solder it and use an adhesive-lined heat shrink tubing. That way, when you heat it up, the tubing will conform to both ends and seal it with adhesive. Get a medium-walled tubing and it will give your joint a lot of support.
Like the others, I'd solder and heat shrink, that's what I have done on my car.
I've heard this before and have been told that soldering of wires is not allowed on aircraft for this very reason. Whether it's true I don't know, but there's a few aircraft mechs on this site, maybe they can chime in.
I've heard this before and have been told that soldering of wires is not allowed on aircraft for this very reason. Whether it's true I don't know, but there's a few aircraft mechs on this site, maybe they can chime in.
blasto9000
Well-known member
I work for a major automaker, and we crimp all wire connections for some of the reasons mentioned above. Only component leads are soldered.
My friend installs alarms and remote starts. He will use a pair of wire strippers and cut the wire insulation 3/4 of an inch apart. Then he will take a razor and slice the insulation off. This leaves the wire intact and care in a 3/4 inch spot. He takes the strands and splits them in part looking like a circle. He twists the wires into the circle and then closes it back up. Solders and heat shrink tubes them.
He never gets call backs due to his wiring skills.
He never gets call backs due to his wiring skills.
Sparkfarmer
Well-known member
This
Lotek
Well-known member
Like the others, I'd solder and heat shrink, that's what I have done on my car.
I've heard this before and have been told that soldering of wires is not allowed on aircraft for this very reason. Whether it's true I don't know, but there's a few aircraft mechs on this site, maybe they can chime in.
Crimp and heatshrink are recommended for boats as well, for the same reason.
This
How does he get the heatshrink on an unbroken wire?
I have seen this kind of joint fail on occasion, more often I see the ones where the guy skips the solder step and puts a tiewrap over the joint to keep it tight then layered with cheap electrical tape that gets loose and leaves live bare wires under the dash.Actually the best way to do the job is to run all the wires back to the fuseblock and fuse them separately, that way if one component shorts and blows a fuse, it will be easier to diagnose.
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Lotek
Well-known member
You can't do communication wires that way, they have to be serial, signal and control ckts will be separate unless you are tapping into a tach output to the ecm for a gauge or something like that. I am assuming that the O/P is talking about power or ground wiring, ground should terminate in a non-rusty area (hard on a Jeep, I know),
and power should run back to the fuse in an unbroken ckt to minimize voltage drop. The problem with using tape to insulate is that it can move, unravel or get brittle and crack, it doesn't provide a long term weatherproof seal.
Yeah I'm nitpicking, but after you have traced an intermittent short that kills the car on the freeway every month or so, and find it's caused by a ten year old alarm on a15 year old corvette that was tied into the ckt with a crappy connection that blows the fuse but by the time you get it it has moved away from where it's shorting, and the customer doesn't understand why you can't find the problem because the dipshit alarm installer hid his connections "for security" and calls the factory to complain, which prompts the service mgr to pull you off jobs that pay the bills, you will nitpick too. But that was my day...
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On the rare occasion that I use electrical tape to wrap wires, I follow it up with skotch-kote (find it in the electrical section of the box stores). The stuff makes one hell of a seal around connections. I started using it on my plow truck to seal up wiring and ground locations.
ive never had to take it back off but I imagine its a ***** to remove
ive never had to take it back off but I imagine its a ***** to remove
Here's some tips / experience I have gained over the years soldering wires......
1) Soldering:
I personally like a soldering gun ....a half pull on trigger will heat it up fast (you will feel and hear the humm) - a full pull will maintain the heat (no humm).
Keep a wet sponge, some soldering flux and good quality 60/40 (0.063") diameter rosen-core soldering wire handy.
"tin" your soldering tip by heating, dipping in flux, and touching with solder - this will help with heat transfer. If your tip gets dirty ....clean with a wire brush and repeat above.
heat from one side of the wire and add solder to the other side (you want the "wire-heat" to melt the solder). You get a bad "cold" joint if you don't follow this rule.
Minimize the amount of solder you use... too much and it will get drawn back along the wire (under the sheath) and create a hard sport that could break (and be difficult to detect).
Some good pictures on www.fordfuelinjection.com.
2) Heat Shrink: www.waytekwire.com. What I didn't realize is that there is a big difference between "single wall non-adhesive" heat shrink and double wall adhesive heat shrink. The double wall stuff is far superior. A Milwaukee variable heat gun makes quick work of heat shrink
1) Soldering:
I personally like a soldering gun ....a half pull on trigger will heat it up fast (you will feel and hear the humm) - a full pull will maintain the heat (no humm).
Keep a wet sponge, some soldering flux and good quality 60/40 (0.063") diameter rosen-core soldering wire handy.
"tin" your soldering tip by heating, dipping in flux, and touching with solder - this will help with heat transfer. If your tip gets dirty ....clean with a wire brush and repeat above.
heat from one side of the wire and add solder to the other side (you want the "wire-heat" to melt the solder). You get a bad "cold" joint if you don't follow this rule.
Minimize the amount of solder you use... too much and it will get drawn back along the wire (under the sheath) and create a hard sport that could break (and be difficult to detect).
Some good pictures on www.fordfuelinjection.com.
2) Heat Shrink: www.waytekwire.com. What I didn't realize is that there is a big difference between "single wall non-adhesive" heat shrink and double wall adhesive heat shrink. The double wall stuff is far superior. A Milwaukee variable heat gun makes quick work of heat shrink
rsanter
Well-known member
I like using an uninsulated crimp connectir and then solder the whole thing.
slide on the shrink tube and go
bob
slide on the shrink tube and go
bob
aussiek2000
Well-known member
I always solder and heat shrink. The key is to use enough solder to make a solid connection, but not such that it starts "soaking" into the wire under the insulation creating a hard spot. I do not use flux as it leads to corrosion down the road. A good iron and 63/37 quality solder will do wonders. I forget the term, but 63/37 both melts and hardens at the same temperature, which means as soon as you remove your iron the joint is solid and you don't have to keep holding it while the solder cools down leading to a cold solder joint.
Alchymist
Well-known member
Eutectic solder. Guess it's up to personal preference weather to crimp or solder. Military uses tons of both type. Many connectors are crimp terminals, others are solder cup. Notable that most solder cup types get potted, few crimp type do. Lends credence to the vibration breaks solder connections theory. Important lesson to take away here is the use of the heat shrink tubing, preferably the hot melt adhesive type. I've been known to put two layers on in high vibration spots. One layer slightly longer than the splice, then one over that a little longer.
I have seen GM use stuff like this on late model engine harnesses where they are tying multiple small grounds into a single slightly-larger ground. They use this stuff and cover it with a non-adhesive lined heat shrink tubing.