I have a Ariens self propelled lawnmower that I happend to hit a iron marker(pipe) with. When the blade hit the pipe, the lawnmower jolted and the engine stopped. I took a look and the blade still intact except for a nick on the edge. I replaced the flywheel key because it got broken when it hit the pipe. the engine turns on but it vibrates in such a way the looks like the shaft might be out of aligment. is there a way to check the aligment? and if so, can it be reset? or is the mower finished?