spark plugs

[corleone]

What are mine trying to tell me?

Electrode very black with lots of carbon so its a rich mix/bad choke. On two of them the insulation has a black ring round the base and all have a sticky oily substance around the threads but not on the electrode.

I'm thinking that this could be due to worn rings (piston! ) but is the black ring on the insulation just down to the replacement being a couple of years overdue?

ta!

[toomanytoys]

Only reall way to check is to take it up the road get it up to temp and do a hill in 3rd full throttle.. then dip clutch switch engine off and stop.. pull the plugs to see if its the same.. if all you have done is run local and short trips it doesnt say a lot.. they will be black as running on choke, not under good load..

if you think they are overdue, then change them, do a full service and check timing, CO etc.. then do the "plug chop"

sticky black residue on the threads is prob from a slight leak on the plug.. some partially burnt gases escaping and condensing and turning to goo..

[T3teedub]

If you are serious about the "couple of years overdue" then treat yourself, and the van, to a new set. You know it makes sense