1. Take the extruder assembly off the machine.
2. Remove the 4 screws on 2 sides of extruder assembly with 2.0 mm Allen-Key, and remove the black cover, (Figure 3.4 - 1). Then, unplug the cable of motor on interconnection PCB.
3. Remove the 6 screws with 1.5 mm Allen-Key shown in Figure 3.4 - 2, then take the motor together with the frame off the extruder assembly.
4. Remove the 4 screws on the frame with 2.0 mm Allen-Key, and take the motor apart from the frame. Figure 3.4 - 3.
5. If the new motor has no gear with it, take the gear off the old motor and install it onto the new one. Loosen the 2 set screws on the gear, and take the gear off (You could need a puller here) Figure 3.4 - 3
6. Follow the above steps reversely to recover all the stuffs.