Is it possible to re-insulate small copper wires?
 

I have a small harness from a '90s Mercedes, (biodegradable wire insulation), that is NLA as a new part from dealer or anywhere else. Bastards. :mad:

I could fix it if I could just put new insulation on wires. Otherwise, I'd need to solder new wires on and that's a PIA for me. Is there such thing as plastic or rubber insulation that I can slip on these and heat or something?

TIA. :cool:

There is ordinary heat shrink for wiring - but you know about this stuff already.

Liquid tape. Apply it with a brush.

https://www.homedepot.com/p/Gardner-Bender-4-fl-oz-Liquid-Electrical-Tape-Black-LTB-400/100119178

Not sure how extensive your damage is, i cant imagine doing all the wiring. However yo can get fine gauge silicone or rubber hose and put a single slit in it. Put it over the wiring and wrap in fiberglass electrical tape. Would work well for small repairs

PTFE (Teflon) shrink-tubing and a heat-gun.

Thanks, it's just a small harness w 3 thin wires, the longest of which is about 4' long. Here are a couple pics:

http://forums.pelicanparts.com/uploa...1514353063.JPG
http://forums.pelicanparts.com/uploa...1514353063.JPG

Pretty ugly. I would probably use heat shrink tubing.

Looking at the photos... You're much better off replacing the wires!
You could muck around with heat shrink tubing etc but IMO it would be easier to replace them.

This is worth a look.

Engine Wiring Harness rebuild DIY step-by-step - Mercedes-Benz Forum

I know that it looks ugly but the "business part" of the wires is fine, (the actual copper wire). It's just the insulation that's disintegrating.

https://www.amazon.com/F4-Tape/dp/B01IVNQ7RC

This is self fusing tape. Easier to apply than heat shrink tubing, but will not come apart like electrical tape.

This.

Are the connectors still available? If so, why not make a new harness?

What I was thinking, cut and splice / solder if you have to and reinforce around the soldering points to prevent fracturing.

If it's not critical to running and not too hard to access I'd even use butt connectors. Strip the wire all the way to the connector, leave about 2" of bare copper showing going up to the connector, cut the old wire away.

Take another piece of fresh wire about same gauge, strip the casing off and save the casing- slip it over the 2" bare wire going to the connector, you have just reshielded the wire. Butt connect it there to hold it in place.

Connect fresh wire between the two terminals. Done. Put in loom for protection

I do this when I install capacitors inline for audio, works fine.

rjp

Looks like great stuff but not sure how I'd insulate small wires w it(?)

Looks great, would I have to wind each wire like regular electrical tape or is it applied lengthwise?

Thought about doing this as well. The advantage to recoating the wires somehow is that all of the resistance should be 100% correct as from factory. They are not critical to running but do connect to oil pressure sender/gauge, oil level sender and starter solenoid.

Butt connectors and the same gauge wire would probably work fine.

I can't forgive MB for doing this, just shameful. :(

There are companies out there that make reproduction wiring with cloth ( and other types) of insulation in various gauges for vintage automotive restoration applications. You'll need to do some digging, but I've seen their websites as I was looking for something similar a few years back.

For terminal ends, you may have to improvise with something modern by removing the insulator and gently wire brushing the end to remove the surface aluminum coating.

I agree it is shameful but the intention was good. MB should have provided a fix for free but there were lots of cars affected.
However they did fix the issue if it occurred whilst the car was under warranty.

Mercedes Benz Defects - Exposing irresponsible engineering failures

Like the water cooled Porsche engines and their issues. IMO Porsche should have fixed all of them no questions asked.
Everybody keeps telling me it's only a small percentage of engines that are affected. If that's true why didn't Porsche fix them?

I’ve noticed some parts for my W126 and starting to show up as NLA. You would think mercedes would keep a steady stream of parts available, especially for cars that gave them a good reputation and have a good enthusiast base.

Wait till the part gets to the classic restoration center, it might as well be NLA with the prices they charge.

rjp

can you paint them with plasti-dip?

That's not a valid reason. A properly made harness will work fine.

If anything a new proper harness will be better than the corroded connections in your picture. I would not even consider recycling that pile of corrosion.

from what i've seen of you on other portions of this website, while i have the knowledge you need, i can't find it in myself to help you

Apply just like regular electrical tape and it will eventually fuse together.

I've already gotten the help I need from people better than you. If everyone let PARF determine who they help on technical issues, this board would suck. It doesn't suck.

I'm glad you chimed in, though. I'd have never known you exist, otherwise. :cool:

It's out of the car and there on the bench? I would rather solder in new wire than try to wrap all that in tape.

When your wiring starts snapping the coating when bent, it's time to replace the offending wires with new. I have seen situations where only the end 6"-12" of the plastic insulation has become brittle (and breaks easily), and can either be cut back, or splice in a new wire, or replace all the way from the connector.

I wouldn't try to fix the wires in the picture because the coating will crack in in another place.

I've never been able to solder worth a damn. Maybe it's time to up my game. They would need to be tiny solders @ the triple plug in order to not have the wires short on each other.

I was planning on replacing all of the insulation on the copper wires, not just in spots. I'm going to examine the patient some more tomorrow. Thanks all! :)

Well, most all. ;)

I used clear heat shrink tube on my wife's W140.

The clear allowed the non-degraded color-coded sections of the wire bundle to be preserved.

The downside is that HeatShrink is less flexible.

But what do I know, you just called me an imbecile in PARF because you thought I had some thing wrong (but it was you who was wrong.) Nice guy eddie, eh?

You should stick to technical topics, where you are brilliant, as opposed to politics, not so much. :)

You can use this to dip or paint on the wires but looking at them you should make a new loom with new wire. The resistance built up in the corroded old wires might not make whatever they connect to operate correctly.

http://forums.pelicanparts.com/uploa...1514471310.jpg

I thought Lucas had a patent on biodegradable wire insulation?
Maybe it expired in the late 40's?
Bill K