I have had this happen before(I dont use loktite there) & wondered what the culprite is? When your bearings over heat some times the bearing will stick to the crank ,I just was always able to get the bell off with a little work but never found a good sounding awnser what the "stick" is other than galling but the discolored part of the crank where the bearing was, mic's the same as the shiny part of the crank.