Doing some preventive maintenance on my 1999 200 Optimax (ser. #0G886121), and pulled the plugs. Every plug looked exactly the same except for the one that came out of the #6 cylinder. In the attached photo, the plug on top is how #1 - #5 looked, and then my #6 is the one on the bottom (which is much more black and sooty looking). Anything to be concerned about??? The motor seems to run ok. I was doing this preventive maintenance work because it stumbled on me coming out of the hole the other day, and I just wanted to replace all the basic stuff. Thanks in advance for any ideas.
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