Canon JX500 Service Manual page 84

Never loosen the paper feed motor red screw [
RED) M2.6 × 4] other than for replacing the paper feed motor. Refer to
5-1 Paper feed motor adjustment
6-1-2 Precautions for Timing Slit Disk Film
6-1-3 Precautions for Removing CHASSIS UNIT
for the details.
Never leave the timing slit disk film anywhere it
deforms when removing the paper feed roller
ass'y. Never touch the slit pattern of the timing slit
disk film. Never adhere grease to the timing slit
disk film. Never reuse the grease-removed part.
Replace the timing slit disk film with new one if
grease is adhered to the timing slit disk film.
Remove the DS sensor (2) before removing the
B-Tight Screw M3×44 (1) when removing the
Chassis Unit.
Part 1 - 76
TP (Mach, Truss Head:
Part 1: 4-