Brother HL-4140CN Service Manual page 309

(2) When mounting LY0198001 Drum idle gear Z64 and LY0199001 Drum idle gear Z64
first of Nos. 3 to 5, mount them by aligning their phases as shown in the figure below.
Top drive ASSY
Drum idle gear Z64
3
Mark
Mark on the sheet metal
Align the phase of the mark
on the gear to the mark on
the sheet metal.
Drum idle gear Z64 first
4
Mark
Motor gear
Align the phase of the mark
on the gear to the center of
the Motor gear.
Fig. 4-3
4-11
Drum idle gear Z64
5
Mark
Mark on the sheet metal
Align the phase of the mark
on the gear to the mark on
the sheet metal.
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