Brother MFC-3340CN Service Manual page 151

Removing the maintenance unit and related parts
(2) Remove two screws, "e" from the top of the engine unit and "f" from the right side of the
maintenance unit.
(3) Remove the maintenance unit.
(4) Unlatch the purge cam switch from the maintenance unit.
(5) Remove the purge-related parts from the engine unit as shown below.
NOTE: Take care not to let the springs bounce off.
Clutch gear spring (shorter)
Top of the maintenance unit
Purge lever
Reassembling Note: When setting the idle gear L back into place, face its ribs inwards.
Reassembling Note: If you replace the engine unit, make adjustments specified in
Section 6.2.
Clutch gear
"e"
PF roller gear R
ngine unit
5-53
Purge lever shaft
Purge lever
Purge lever spring (longer)
"f"
Purge gear
Idle gear L
Ribs
"e": Taptite, cup B M3x8
"f": Taptite, cup S M3x6
Purge cam switch
Maintenance
unit
Latch
Idle gears S
Chapter 6,
Confidential