How much of a no-no is soldering a wiring loom?

My loom got slightly mashed by the diff flange a while back and im no looking to do a proper repair on it.
- Theres about 10 wires going down the tunnel in the loom, plus on extra for the fuel pump.
- Of which three have been severed and two had the insulation slight damaged. Plus the fuel line that was cut (what alerted me to the problem).

The fuel pump feed i can just shorten, crimp with a crimp joiner with some silicon grease in it. Job done.

But i cant shorten the three severed wires (two have had about 10mm taken out of them) and crimp so im wondering how frowned apon it would be so solder in a section of wire here, with some shrink wrap over each wire, and tape over it all in loom tape.

Will this be likely to fracture or fail? I think its the tail lights and rhs indicator. Nothing important... :p


Daniel

I think crimping a section in would be frowned upon more that doing a proper job and soldering a section in?

nothhing wrong with soldering. thats the proper way to do it

If it is shrink wrapped well no problem at all.

Stu

soldering is far beter than crimps as you get much better conductivity between conducters so less resistance= less heat generated on high power circuits. use heat shrink sleeve aswell and itll be as good as new

solder and heat shrink tube - no problem.

The only issue with soldering is when you solder a connector on a flexing wire which is then fastened on to something which doesn't move. It will probably then fail.

in your situation it sounds fine

Solder makes for brittle joints, a well known problem in the car industry, they much prefer crimping.
In your case a soldered joint would probably be better than crimping to repair the loom, do make sure you wrap and support the repaired bit.

quote:

---

Originally posted by snapper
Solder makes for brittle joints, a well known problem in the car industry, they much prefer crimping.
In your case a soldered joint would probably be better than crimping to repair the loom, do make sure you wrap and support the repaired bit.

---

I always thought the car industry preferred crimping because you can get idiots to do it without any training or skill. The ratchet crimping tool provides the quality control. Oh, and it's faster.

Crimping for me.

HOWEVER.....
Use the proper ratchet crimpers (now about £10 a pair). NOT those £2:50 pliers. They do not crimp up to the correct tension and will give rise to connection problems in a few years.

On anything that is exposed to weather or water. I usually just wrap a bit of self amalgamating tape around the crimped joint to fully seal it.

Having spent 40 years as a BT engineer, I have seen all sorts of methods of jointing and then sealing to keep out the water.

I am also a Radio Ham, and have used Silicone Rubber grease inside the joint (aerial connectors and crimp joints) to prevent corrosion from ingress of moisture, and sealed the whole connectors in S/A tape.
Some of these joints have been at the top of my antenna mast (30ft above ground) for 20 years, and when inspected after that time, they were still perfect and shiny (Silver plated contact and bodies on the connector).
So I KNOW this works, and works well over long periods of time.
There is nothing wrong with Soldering, as long as its done properly. However, Dry joints are a nightmare to fault on (So are poorly crimped joints).
Crimping, and ensuring they are weatherproofed (when necessary) is a perfectly good way of doing things.

Have the best of both worlds and use a heatshrink butt splice.
You crimp then heat to shrink down the adhesive lined insulation.
Not quite as bulky as crimp splices but you may still have to stagger the splices to stob getting a bulky loom.
Linky

quote:

---

Originally posted by snapper
Solder makes for brittle joints, a well known problem in the car industry, they much prefer crimping.
In your case a soldered joint would probably be better than crimping to repair the loom, do make sure you wrap and support the repaired bit.

---

quote:

---

Originally posted by minitici
Have the best of both worlds and use a heatshrink butt splice.

---

If crimping it pays to use a pro crimping tool, those nasty cheap crimping pliers are useless.

soldering will work - been doing this today.

strip about 12 mm of insualtion. if wire is black, then rub with wet'n'dry until shiny.

splay the ends, push together and twist.

tjhis ensures you have good contact so are not relying on the solder.

to prevent the wires unravelling, I use a single strand of wire wound round the joint.

apply some flux then apply flux.


someone will come along and say that solder is not good as it will fracture the wire over time due to vibrations but if the wire is supported so it does not flap round, can't see it happening for quite a few decades.

quote:

---

Originally posted by fazerruss
soldering is far beter than crimps as you get much better conductivity between conducters so less resistance= less heat generated on high power circuits. use heat shrink sleeve aswell and itll be as good as new

---

Both methods have advantages, soldered connections can suffer from dry joints and can have a lower mechanical strength than crimps.
Crimps on the other hand are the prefered method for aircraft engineering and to be honest provides a much more reliable electrical and mechanical connection than soldering.
However, crimping to an acceptable standard can not be done by "idiots without any training or skill" the correct tool must be selected for the appropriate cable / application and the mechanical integrity of the crimp should be inspected.

Holy thread resurrection batman! (almost 10 years, but hey better than starting another thread right?)

So....

I have a BYD TFSI engine (Golf Edition 30) in an S1 Elise (it ultimately replaced my BEC Fury).

The engine loom near the ECU plug has issues where for example the female ECU plug pins have been probed too hard with a multimeter and splayed them open. To the point where if you kick the loom near the ECU a firm prod it can throw error codes and apparently even make it cut out.

Time to make good. Considered a total re-pin using a load of the correct pins and a £100 crimp tool, a new ECU plug and hours of patience.

Then I thought just get the last foot or two or an existing OEM loom and splice that in.

Which brings me to this thread and the question, is something like these heatshrink butt connectors the best solution for this application:

https://www.ebay.co.uk/itm/100-4-Solder-Sleeve-Seal-Heat-Shrink-Electrical-Butt-Wire-Terminal-Connector-Kit/202714481930

If so I'm off to buy the 250pc multi pack.

Out of interest while Googling I also found this document from NASA...

https://workmanship.nasa.gov/lib/insp/2%20books/links/sections/files/407.pdf

[Edited on 12/9/19 by hobbsy]

quote:

---

Originally posted by 02GF74


to prevent the wires unravelling, I use a single strand of wire wound round the joint.

apply some flux then apply flux.

.

---

I bought some of the heat shrink solder joints today - basically heat gun or blow torch the joint and the wrapper shrinks and solder melts into the joint.

Seem to work a treat and lots quicker than a normal solder joint and heat shrink, plus no forgetting to put the shrink wrap on and not realising until you have soldered the joint up.

They are also great for where you have very little cable to play with and so no room to slide the shrink wrap out of the way whilst you solder.

Stu

I'm in the proper crimping camp. Tools are cheap and far more reliable than soldering.

EDIT: Also to add, I am a convert after having solder joints fail.

[Edited on 12/9/19 by theduck]

I use both methods.

Ok, so I've order some of those solder seal connectors, and some heatshrink crimps and also I can solder and have regular heatshrink

So all 3 options covered

But I'm keen to do some destructive testing first on the solder seal connectors - never used them.