Lexmark X 850 Owners Manual

Repair information4-283
7500-XXX
Duplex drive gear 28 tooth removal 
1.Remove the duplex unit assembly. See “Duplex unit assembly removal” on page 4-277. 
2.Remove the two screws securing the duplex lower guide (A) to the duplex unit assembly.
3.Remove the duplex lower guide (A).
A
Right 

4-284MFP Service Manual 7500-XXX
4.Open the duplex unit assembly.
5.Release the hook of the duplex left door support strap (B) securing the duplex left cover (C) to the duplex 
unit assembly. 
6.Remove the four screws securing the duplex left cover (C) to the duplex unit assembly.
7.Remove the duplex left cover (C). 
B
C HookB
Left 

Repair information4-285
7500-XXX
8.Disconnect the connector of the harness from duplex drive motor assembly (D) to the duplex main cable 
assembly.
9.Release the harness from the clamps of the duplex unit assembly.
10.Remove the three screws securing the bracket (E) to the duplex unit assembly.
11.Remove the bracket (E).
12.Remove the two duplex drive gears 33/74T (G).
13.Release the hooks securing the three duplex drive gears 28T (F) to the duplex unit assembly.
14.Remove the three duplex drive gears...

4-286MFP Service Manual 7500-XXX
Duplex drive gear 33 / 74 tooth removal 
1.Remove the duplex unit assembly. See “Duplex unit assembly removal” on page 4-277. 
2.Remove the two screws securing the duplex lower guide (A) to the duplex unit assembly.
3.Remove the duplex lower guide (A).
A
Right 

Repair information4-287
7500-XXX
4.Open the duplex unit assembly.
5.Release the hook of the duplex left door support strap (B) securing the duplex left cover (C) to the duplex 
unit assembly. 
6.Remove the four screws securing the duplex left cover (C) to the duplex unit assembly.
7.Remove the duplex left cover (C).
B
C HookB
Left 

4-288MFP Service Manual 7500-XXX
8.Disconnect the connector of the harness from duplex drive motor assembly (D) to the duplex main cable 
assembly.
9.Release the harness from the clamps of the duplex unit assembly.
10.Remove the three screws securing the bracket (E) to the duplex unit assembly.
11.Remove the bracket (E).
12.Remove the two duplex drive gears 33/74T (F).
ClampsD
Rear
E Rear
F
FConnector 

Repair information4-289
7500-XXX
Duplex drive gear 33 tooth removal 
1.Remove the duplex unit assembly. See “Duplex unit assembly removal” on page 4-277. 
2.Remove the two screws securing the duplex lower guide (A) to the duplex unit assembly.
3.Remove the duplex lower guide (A).
A
Right 

4-290MFP Service Manual 7500-XXX
4.Open the duplex unit assembly.
5.Release the hook of the duplex left door support strap (B) securing the duplex left cover (C) to the duplex 
unit assembly. 
6.Remove the four screws securing the duplex left cover (C) to the duplex unit assembly.
7.Remove the duplex left cover (C). 
B
C HookB
Left 

Repair information4-291
7500-XXX
8.Disconnect the connector of the harness from the duplex drive motor assembly (D) to the duplex main 
cable assembly.
9.Release the harness from the clamps of the duplex unit assembly.
10.Remove the three screws securing the bracket (E) to the duplex unit assembly.
11.Remove the bracket (E).
12.Remove the two duplex drive gears 33T (F). 
FD
E Rear
Clamps
FConnector 

4-292MFP Service Manual 7500-XXX
Duplex drive gear 42 tooth removal 
1.Remove the duplex unit assembly. See “Duplex unit assembly removal” on page 4-277. 
2.Remove the two screws securing the duplex lower guide (A) to the duplex unit assembly.
3.Remove the duplex lower guide (A).
A
Right