451 shaft cause to change intermittenly the gear

[akbareshghi]

please help me about repairing the shaft which cause this problem
thanks a lot for your comprehensive troobleshooting and open the motor of shaft
bad gear failed to rotate the gears of transfer belt then image quality go bad
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[ncbabak]

[Cause]
The width of the transfer belt cleaner gear is insufficient when engaged with the cleaning motor gear.

[Countermeasure]
The contact width of the two gears will be extended from 5.3mm to 9.0mm in order to keep proper mesh.
This change improves the contact gear ratio from 2.6 to 3.4 and safe factor from 2.7 to 4.7.

Three parts should be replaced and one new part (collar) is added at the same time as shown in illustration.
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