I'm in the middle of a rebuild and was starting to inspect the rotors when something in the FSM troubled me.

When cleaning the rotors, the area between the side seal and face had what seemed to be carbon deposits. After getting all of the carbon off, it was more metallic in nature. Basically there were small deposits of something metallic in that area.

I managed to get the surface smooth again, but when looking at the FSM again in the cleaning section they mention that there is a soft metal coating in that area. It seems that that coating at some point failed and started to deposit on the side of the rotor. Some of the original surface is there but some is gone.

I haven't seen any mention of this on the posts I've looked through up to this point.

So my questions are:
How important is that metallic coating?
Are the rotors still usable if they spec out?
Are there any options aside from replacing the rotors?
Any thoughts as to what may have caused this to happen?

Thanks for the advice.

Gary

 

try posting pics of that area, and then someone can tell you what exactly you are talking about.