Something doesn't add up. If you jumped the smaller solenoid terminal to the larger battery terminal on the starter solenoid, and the starter cranked the engine, the cables and connections have to be good. If the solenoid engages with a nice strong clunk when you turn the ignition switch to "crank", that control circuit is working. Put the two together and the starter should crank the engine when you turn the ignition switch.
If that sounds right, the only thing you're bypassing is the starter relay and solenoid circuit. The small added resistance of the wiring could possibly by reducing the voltage to the solenoid if the battery is not fully-charged. It would not be common, but that could make the solenoid strong enough to make noise when it moves, but not quite strong enough to move far enough to turn on the high-current starter motor circuit. That would be weird, but to check for that, either measure the battery voltage, (should be 12.6 volts), or try jump-starting it from another car.
So I'm clear, you are jumping the smaller solenoid terminal to the large terminal the positive battery cable is attached to, right? You don't want to be jumping to the other large terminal with the braided wire that goes into the motor.
Tuesday, July 21st, 2015 AT 11:26 PM