Upon closer inspection of my front rotor housing, I see what looks like a very smooth, very small scar on the housing. It starts at the leading (top small hole) spark plug area and goes about 1.5" up the rotor housing. I have no idea what would cause that. My question is...how bad is too bad to be used again? I want to emphasize that this scar is SMOOTH and very very shallow. It can be felt with my fingers more than seen, though it is somewhat visable. Nothing drastic at all.

-Joe

 

Thats a common thing .I had a housing just like that. If you are just using it for stock use....sure...depending on how shallow it is. If you are going for big #'s, forget it.

 

the top hole is the trailing plug... dude....

That little groove, many of us think, is cause by carbon deposits or minute metal fragments melted off the plug...