Small Engines (Lawn Mowers, etc.): Simplicity Regent Tractor Starting Circuit, screw drive, switch problem

Question
My simplicity 12 HP lawn tractor won't turn over with a new battery or jump start. The solenoid clicks but wont turn over (the motor is not seized). If I hook up 12 volts directly to the starter with the ignition switch off the starter runs but does not engage. If I turn the key switch to the run position the starter disengages with the direct 12 volt connection from the battery. I jump across the battery post to the starter post on the solenoid with a screw drive and nothing happens. The circuit breaker is good. Please help me with my problem. Thanks LJ.  

Answer
When you put 12v directly to the starter, you just energize the starter, not the solenoid, so the starter just spins. You will need to hook a small wire from your main wire you've jumped to the starter and hook it to the small stud your ignition wire goes to on the solenoid. If this starts it, you  could have a safety switch problem, or the solenoid could be bad. I do not work on simplicity, so I cannot answer the safety switch problem for you.