Canon imageRUNNER ADVANCE C5000 Series Technical Workbook page 139

17) Clean the both surfaces of the disk-shaped encoder [1] with alcohol.
[Caution] Be sure not to bend the encoder when cleaning it.
18) Install the Drum Speed Detection Unit to the Drum Drive Unit (Bk) with 1 screw. Then connect 2
connectors.
19) Open the Process Unit Inner Cover.
20) Install the Drum Drive Unit (Bk) [1] by slightly tightening the 3 screws [3]. Then connect the two
connectors [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 22). This causes failure in the output image. Thus, be sure not to fully tighten the screws.
21) Install the Drum Cap [1] with 1 screw [2].
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