Canon iR4570 Series Service Manual page 536

Chapter 9
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2) Lift the front of the pressure roller [1].
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3) Push in the bush [1] found at the rear in the
direction of the arrow to free it; then, detach the
pressure roller.
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Be sure to pay attention to the position and the
orientation of the insulating bush.
9-22
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The insulating bush may be of 2 different shapes: one
for the iR3570/4570 and the other for the iR2270/
2870. If the machine is an iR2270/2870, be sure to pay
attention to the direction of the protrusion of the
insulating bush.
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