I have a Craftsman push 21" mower with a 6.5 Briggs. (#917388971). It hit a rock with the blade, damaged the blade, and broke the bolt off. I managed to remove the part that remained in the mower. When I pull the starter chord, it seems to pull a bit hard in one place, and not sure if that is normal. My concern is that the crank may be bent, and do not want to purchase parts if that is so. Can I try it without the blade? Also the blade adaptor seems to have sheared the shear pin, but willnot come off. Any ideas. RR