Monoprice Select Mini Z axis problem

Been using my 3d printer for months with no serious issues, minus some clogging. I printed off some mods and replaced the hotend with e3d with zero offset. While inside I added a second fan (1 for hotend, 1 for part cooling). Also added the z axis base stabilizers. After I reassembled the printer my Z axis is not working.

I removed the threaded rod and checked the motor. It turns on but seems to go in only 1 direction.
So, I'm guessing I have extra tension prevent from the threaded rod from spinning loosely? But don't understand the single direction. Need help. Any ideas?

Undo the changes made to the Z axis, and see if that helps.

Removed the motor completely. The motor works but only 1 direction