Canon PC300 Service Manual page 90

MECHANICAL SYSTEM
Make sure that the spring is fitted with
the boss in the center of the hook when
attaching the transfer charging roller;
see Figure 4-503.
Spring
Figure 4-503
4-12 COPYRIGHT © 1994 CANON.INC. CANON PC300/520/225, FC210290 REV.0 JULY 1994 PRINTED IN JAPAN (IMPRIME AU JAPON)