Oce 3121 Technical & Service Manual page 632

Remove the E-ring (2) from the gear A (1).
2
Disengage gear A from gear B.
3
By turning the lead cam of the front drive assembly by hand, position it as in-
4
dicated in "Installing the Drive Assembly".
Put the gear A back in its original position. Check the position of the cam, and
5
refit the E-ring.
ed.1 21 Sorter 419