Is my stepper motor broken?

Hi,

I am currently working on debugging my Prusa Mendel i2 and am having the following problem in my prints:

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I think the cause may be in my x axis stepper motor. When the power is off and I move the extruder manually, the extruder will slide about 5mm (around 30 degrees of motor shaft rotation) with almost no resistance. After that I can feel the magnets in the motor slow the movement of the motion. I can move the extruder back and forth about one centimeter with virtually no resistance. Could it be that the crossing over of the fill plastic (in the pictures) is caused by a broken motor? (this lack of resistance when the motor is pushed at first). I am sure that it is not a belt tension issue because the belt is quite tight and is not slipping on the pulley. If anyone knows if this is a problem (and I need to get a new motor) or if can guess at what is causing the print error I would appreciate it. Also if someone has an i2 can you do a quick check to see if your x axis does the same thing as mine?

Thanks in advance for your thoughts/advice!

Stepper motors don't break. The connection between stepper and pulley sometimes does.

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