Just hilighting what appears to be a problem. You stated that you had used up the "bunch" of plugs that you had bought. How many do you typically go through in what period of time.

My personal experience has been to change them once a year unless they blow (which is rare). If you are burning them much more often (as your note seems to imply), perhaos there is more to look at.

For example if you are using a glow attachment from your power panel and keep blowing the Fox plugs by overcharging, the same will happen to the OS.

Just wanted to confirm this wasn't the case.

Bob aka Nuker

ps I use OS #3 in my .15 bushing combats, OS F in all my 4-strokes and OS #8 in everything else