Pfaff expression 2014 Service Manual page 23

Check whether the slide block can be moved easily, but without play or binding.
Push slide lever shaft 16 complete with stepping motor 17 carefully to the left until there is a clearance
of 0.05 mm between slide block 8 and connecting bar 19.
Tighten screw 15 and check whether the slide block moves easily and without play.
Push link 7 complete with feed regulator 6 to the right onto the connecting bar pin.
Push feed regulator 6 to the rear, and then upward over feed eccentric 5.
Position screw 4 in clamping plate 21 and tighten it a little.
Move stud 20 sideways a little until link 7 and connecting rod 19 have a slight play and move easily.
Tighten screw 4.
Attach the two springs 3 and 9.
Cross-check:
The feed dog must be in the exact center of the feed slot.
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