BLADE TOUCHING IN SIDE

[HENRIC]

I HAVE JUST BOUGHT SMALL LAWN MOWER W/SELF PROPEL. WHILE MOWING I HIT THE STONE
AND NOW I HAVE A BIG SOUND WHEN I START THE MOWER. I CHANGED THE BLADE THINKING THAT IT IS BENT. BUT THE SOUND IS STILL THERE. I AM THINKING THE BLADE ROTATING SHAFT MAY BE BENT.
NEED HELP. HOW TO CHANGE THE SHAFT??? IT IS BRIGGS AND NAME IS BRUTE FROM WALMART.
THANKS
HENRIC:

 

[ILENGINE]

If the crankshaft is bent , you are done. New mower is cheaper.