trying,
There should be two small terminals. The one you can jump start it with is called the 'S' terminal, and when powered, it pulls the solenoid in and spins the starter, just as you have discovered.
The other little terminal is the 'R' terminal (relay), and it is only powered when the solenoid is in and the starter is spinning. Think of that small terminal as a switched source for 12 volts. It normally would supply ignition voltage when the key is in START.
Does this make sense.
Stuart
