id turn it upside down and knock out stuff in it out. and then flush it out a few times with gas. then turn it upside down by hand, the shaft or something. the alternator side. and listen for any noises. but do it slowly. and be glad the cranks not moving. right now. go check it, clean it out and see if the bottom end bearings are good. look for a cir clip to come out. whoever put the piston on, there are circlips on both sides of the wrist pin. looking at that picture, i think the circlips gone. maybe both sides. when you put them in, make sure they snap, and turn them, openned, to the sides. it stops the up and down motion, from the force knocking them and flinging htem out.tkae your motor off and flush it out many times. then turn the motor by hand to see if its turning. and if the bottom end bearings are still good. not making any noises. smooth