Starter on a 1996 gmc jimmy. turn the key and it will engage flywheel for a second then just spin freely until i disconnect the battery. why is this happening

 

Its most likely my bendix. just seeing if anyone had any tips or tricks to try before i put a new one in tomorrow(in the parking lot of my place of employment. Joy). its weird how it keeps spinning until i disconnect battery though. that i dont get. and if i touch the cable to the battery with the key in the off position it will still try to start(very rarely) or spin freely until pulling cable away from batt. Any ideas?

 

Could be an issue with the starter solenoid(on the starter). Maybe an issue with the ignition switch, or starter relay(on the firewall IIR
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