funky starter motor!

[audi-driver1126]

i came back from a nice little vacation in the city of Calgary and i went to start my 87 4000S when i got home. The only thing that happened when i turned the key was a loud "clunk" from the starter. Right away i figured either low battery power or somthing to do with my grounds.(i had done some cleaning of all the ground connections before i left) after spending a few tedious hours troubleshooting and tracking, i decided it was a bad starter, i unbolted it and took it out. With further testing i applied 12 volts directly to the solenoid connections, again a clunk from the pinion gear plunging but no rotation. I gave it a few light taps with a hammer and re applied the volts. this time, no plunge of the gear, but i could hear the motor spinning away inside. No rattles, no odd sounds, just the noise an electric motor would make. Now i decided to put the starter half way in the car, hanging from its wires. I turned the key and zing! the starter worked again... Its now securely bolted back in the car and it starts up still. Talk about odd starters.