Brother HL-4040CN, HL-4050CDN, HL-4070CDW Service Manual page 170

(4) Assemble the Lift arm, Feed roller shaft TR and Separation roller drive shaft of the Paper
feed frame unit following the procedure described below.
<Assembling the Lift arm>
Implement the operations below while holding the status described in Step (3).
1) When pushing up the Roller holder ASSY with your hand, the end (section "A") of the
Lift arm goes down. That makes easy to push the end of the Lift arm under the section
"B" shown in Fig. 3-71.
<Left side>
"A"
2) Push up the section "B" of the Side frame L with the end (section "A") of the Lift arm
and place the section "A" under the section "B". Then, put the section "A" into the
space between the Hooks B and C inside the machine and assemble the Paper feed
frame unit into the machine.
"B"
Side frame L
Lift arm
Roller holder ASSY
<Front side>
Fig. 3-70
Paper feed frame unit
"A"
<Front side>
Fig. 3-71
3-61
Paper feed frame unit
"B"
Hook B
"A"
Hook C
Confidential