So you jump across the solenoid terminals and nothing happens? Test the voltage at the solenoid terminals, and if you have battery voltage test what the voltage is while you're trying to start it. If you're not hearing the starter relay engage, the problem is likely the starter relay or whatever should be engaging the relay. Basically, you should verify that all the conditions at the solenoid are correct before you blame the starter motor. It could be a bad starter motor, but there's no use blaming anything until you know what is working and what isn't.