Canon NP6251 Service Manual page 427

Caution:
If you inadvertently moved the paper level indicator drive belt behind the front cover
after removing the front cover, or if you have moved the deck lifter, move the deck
lifter to its lower limit, and move the drive belt by hand until it gives slight resistance
in the direction of the arrow (Figure 8-304, increasing the white area) before
installing the front cover. (If the deck is driven while there is a discrepancy between
the paper level indicator and the deck lifter, the drive system for the paper level
indicator can become damaged.)
Deck front cover
Paper level (white area)
increasing
COPYRIGHT © 1997 CANON INC.
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Figure 8-304 (front view)
CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 8 PAPER DECK-A1
Indicator window
Drive belt
8-23