RE: Improper break-in
if there is no visable scar in the piston or cylinder, you probably are fine how did you determin if you were having a lean run? and for 10 min.
did you get this engine out of the box,and if you did why was it not run in as per instructions they are easy to follow and your engine will live a long life if done right.
OS engines have a short break in, one basic run in, then you can fly with it, just run it a little rich. again the instructions would have covered this thoroughly.
were you flying? did it die because of over heating?or did it just run out of fuel,was there any oil coming out of the pipe when it was running?how many turns was the needle opened(should have been 1 1/2 to 1 3/4 out for the first few flights).
these would be the first things I would want to know, before you would tell if its burnt.
if there was any oil coming out of the pipe then you should be fine.best to read the manual and repeat the break in procedure if your worried, then set the needle acording to instructions and get some flights in before you lean it back out again.