Black Residue

[ml1936]

Looked at some electrics today and noticed black residue on insulation of cables behind sockets sockets and switches, it wasnt all, but most of them. House had been stood empty for years but now someone is living there. Could this be insulation starting to melt???

 

[Taylortwocities]

The wiring is suffering from a problem that is now becoming apparent after several decades.
In summary, in the mid 60's the early PVC cable insulation had some plasticiser compound in it that reacts with the copper to form a green gunge. It is particularly noticeable where there is overheating. It is acidic but can be cleaned off with care (meths).
No cure other than replacement = rewire!

There is more information on this at
http://www.voltimum.co.uk/consult.p...set=&id=2861&universe=consult.index.questions

or Google 'Green gunge wiring'

 

[JohnD]

here's some I found earlier (you will find it sticky to the touch)

you only see it at cut ends of wire, where it comes out. It is worse where hot.

View media item 1630 View media item 1631 View media item 1632

 

[ml1936]

So would you class it has needs improving, or requires urgent attention?

 

[ban-all-sheds]

black residue

green gunge

 

[holmslaw]

..

 

[Taylortwocities]

Well yes, I made an assumption. Seemed the most likely cause.

Could be wrong of course - I've been up to my armpits in it for the last few days doing remedials of green gunge....it does look black when its hanging on the end of wires though -

Untitled

• Taylortwocities
• 28 Oct 2008
• 1

Untitled

• Taylortwocities
• 28 Oct 2008
• 1

 

[holmslaw]

..

 

[Taylortwocities]

Nope, thats good old ghostbusters green slime from the end of the cables.