Canon iR C6800 Series Service Manual page 899

Chapter 13
13.3.2.3.2 Uneven Density in the Form of a Feedscrew in Color Images
0005-5640
Cause
The developing assembly lid is not fitted correctly when a color toner is replaced.
Field Remedy
Take out the color developing assembly in question from the machine, and fit its lid so that there is no gap.
Be sure to force the lid against the developing assembly so that there is no gap in the area [1] indicated in the diagram,
i.e., not permitting insertion of a transparency.
[1]
F-13-14
When tightening the screw, be sure to take care so that the shavings of the lid of the developing assembly or its lid
will not enter the assembly (i.e., shavings occurring as a result of tightening the screw).
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