Question about discolored sparkplugs

[Pronto]

Yesterday I was looking at a sbc in a MC. I noticed the spark plug insulators from the boot to the metal base had turned all black. I have never seen that before. I didn't wipe them to see if it was soot but it didn't look like soot. All the plugs were discolored. The boots weren't discolored. The bases were all rusty too. Any idea on what's going on with them?

 

[Little6pack]

Yesterday I was looking at a sbc in a MC. I noticed the spark plug insulators from the boot to the metal base had turned all black. I have never seen that before. I didn't wipe them to see if it was soot but it didn't look like soot. All the plugs were discolored. The boots weren't discolored. The bases were all rusty too. Any idea on what's going on with them?

That sounds vaugly familiar..

I see the genuises in here have no comment.. should have tried the more tech savy guys in the tech section. :tongue: