Small Engines (Lawn Mowers, etc.): craftsman mower, starter problem, cable ends

Question
I have a craftsman 17hp briggs engine/ 42 inch mower (model 917270711) Battery was dead so I bought a new one.  Now I have plenty of power but the starter will not turn over.  It only makes a humming noise.  Didn't know if that is a starter problem or condenser or what to try next.  Thanks.

Answer
Remove the spark plug(s) and see if the starter will turn the engine.  If the starter still will not turn the engine, remove the engine blower shroud, the top engine cover, to access the starter and make sure the starter gear is not binding or jammed.

Did you clean the battery cable ends and the battery terminal posts with a wirebrush before you connected the new battery?

Eric