dosent look like hammering, more of a score mark, the bearing sounded a little rough, not megga, but still spun smooth, its now been replaced and the lug replaced too!, the case has been repaired, but ill have to find out how that was done. as its been repaired since i saw it last. could cases be incorrectly fitted? With a shagged bearing and broken lug, could the bits fall in crank side? and get draged into the piston/chamber? the diagram looks sealed? but i can never figure out these things somtimes, someone who has had them apart a few times might be able to answer that?