Small Engine Troubleshooting Problems? Ask a Mechanic Now.
What is the engine model number?
Do you have a voltmeter to test battery voltage when you engage the starter??
If voltage drops below 8 volts, battery or cable problem.
If voltage stays up,starter is bad,
On the engine cover.
OK, how old is battery?
That is the model of the mower.
Without meter to test, I would replcae the starter.