Filament motor not rotating


Hi all,
I totally disassemble the 3D printing module because the filament was not going through the heating head.
I found out that it was the motor that should guide the filament and push him down that was not working. (Green lines are not smooth, is it normal ?)
Anyone have some clues why the motor is not turning ? Should it be turning freely because mine is absolutely not turning (parts are too close to each others) ?
How to repair it ??

PS : it stops working unexpectedly. Nothing wrong before this issue.


Most of the time it is the grub screw holding the gear that is loose. The stepper motors usually don’t break easily.

No, stepper motors don’t usually turn freely because of strong magnetic force, even when there is no electricity applied to them. In fact, it is not advisable to take a stepper motor apart. I’m not exactly sure, but it has something to do with the magnets. You might’ve damaged the motor by opening it.