Originally Posted by pixelsblack009

Hi So I'd taken the head out on my W115 240D to do a valve seat job, and it took some time, now when I went to turn the engine over by hand at the crank shaft pulley it seemed jammed and when I applied some force it came loose and the pistons started to move, it seemed the piston rings had rusted themselves onto the bore and now there's a little lip on the bore where it had rusted itself, so my question is can anything be done besides re-boring and slewing the engine? someone said it can be rubbed off with a very fine sand paper, is this true? also there is some surface rust at the bottom of the bore where I can reach but the piston ring rides obviously