I have a '86 Johnson 110 -
I pull & clean my plugs after about every 3rd trip out -
They're always "clean" but dark & wet? Thing runs great - Bit rough on idle maybe-
They are QL77JC4
Wrong plug?
thats the right plug. dont worry to much about them being black, as long as they are all looking the same. (black is better than covered with melted aluminum !)
To properly check a plug to see how it's burning, take the mtr out and run it at WOT for 5 mins. Shut the mtr down immediatly, then pull the plugs and check them. They should be a nice light brown color if all is well.