Motor is rotating complete assembly

[amijai]

I am trying to study the motion of some components (A turbine, and a motor) using a motor (in motion study) and a belt/chain assembled with parts.
When i start the motion both my motor and turbine starts rotating fine but i only want my motor's rotor to rotate not the complete motor assembly.
My turbine is a part and motor is an assembly. When i study the motion of my motor assembly separately, it works fine(i.e. only rotor rotates, not the whole motor.)
I am attaching the relevant file. Please help.

 

[Johan Moberg]

Are the other parts in the assembly set as "fixed"? If not, right click part, "fix". The other parts should be "float".