Im looking for some input or some knowledge from anyone who knows a bit about spark plugs. I had something happen to me I have never seen before. I have a 175 evinrude XP. This past spring I did my usual run the boat a few times to clean out the fogging and winterization fluids. The first time out I could only reach about 4000 rpm, not quite enough to plane out but it was trying. Then, my rpms came back up like one of the cylinders fired up and I could get up to my 60 mph. Ran fine. This happened again but did not recover. I pulled the spark plugs and found one of them physically could not fire. The ground electrode and the center electrode were touching, like the piston had hit the plug. I purchased 6 new plugs, turned the key fired right up rpms right up there, idles smooth as could be. Pulled all 6 plugs, fine, not a scratch. ANY IDEAS?
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