Weird black run off on keg

[lucas kennedy]

Sorry if im in the wrong section here. Im noticing this weird run off from the black top of my keg. When the area is wet, you can’t touch the black part because youll get that weird black run off on your hands. I noticed this earlier on the bottom portion and was fearful it was mold but no matter how much i scrub, various cleaners, it doesnt seem to go away. Is this something leaching from the plastic/rubber? Anyone else experience this?

 

[day_trippr]

Oxidized rubber?
I have 16 cornies, all old AF, and some of them will leave black marks on anything they bump up against...

Cheers!

 

[PCABrewing]

Is this something leaching from the plastic/rubber
View attachment 752584

It's definitely the rubber breaking down. I don't know what triggers it but I have seen that on other rubber products that have been submerged for extended periods.
Thankfully none of my kegs do that yet.

 

[lucas kennedy]

Thanks for the input everyone! It might be time to start slowly adding in newer solid metal kegs