Brother HL-J6000DW Service Manual page 172

Remove the Head joint rubber from the Head/carriage unit.
(15)
Head/carriage unit
Remove the Plastic retaining ring from the Idle pulley.
(16)
Remove the Idle pulley from the CR frame ASSY.
(17)
Note: Be careful not to lose the Washer which easily comes off from the
Plastic retaining ring
Washer
Idle pulley
CR timing belt
Bosses
Fig. 3-11
CR frame ASSY
Fig. 3-12
3-40
16
17
Head joint rubber
Idle pulley.
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