Ya know those large ribbed rubber boots on our spark plug holes thats supposed to keep water out of the deep hemi head holes.Well they don't seal worth a shet. When washing the bike I must have gotten a bit of water in there and on two holes the plugs look like they are 10 years old with corrosion.The only way for the water to get out is when the cam cover gets hot enough it makes steam,and with the current running through there its a heaven for corrosion. Mabey mine were just a poor fit but it wouldn't hurt to ck.Blowing them out with compressed air and using some kind of grease to seal the ribbs at the top might prevent it happening again..---ROCKY wasnt it you that was asking what the 12 mm allen was for in the tool kit??-It fits the end of that cheap spark plug wrench in the tool kit..Btw all my cam cover bolts were only finger tight when I took them out..All valve clearances are within tolerance.This ck. is really not that hard for what some have been charged for it. Even lifting the cams if you need shims is easy. Crazy Jack