Canon imageRUNNER ADVANCE C5000 Series Technical Workbook page 147

19) Install the Drum Drive Unit [1] slightly tightening 3 screws [2].
[Caution] If the screws are fully tightened here, the Drum Drive Unit is installed with pressure being applied
to the drum shaft when the drum shaft is fitted to the bearing of the Process Unit Inner Cover at the
subsequent step 20). This causes failure in the output image. Thus, be sure not to fully tighten the screws.
20) Close the Process Unit Inner Cover. Install the Front Inner Handle Left Cover [1] and the Front Inner
Handle Right Cover [2] in the direction of the arrows, and tighten one screw [3] for each cover.
21) Push the Drum Drive Unit [1] against the Rear Plate, and fully tighten the three screws [2].
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