Dürkopp Adler 52 i Series Service Instructions Manual page 28

Zigzag stitch mechanism of machines 523, 524, 527
6. Tighten the arresting nut (8 - invisible).
7. Loosen the screw (7).
8. Turn the arresting lever (5) to 1 mm space from the casing (6).
9. Tighten the screw (7).
Information
If the sewing equipment does not allow using the maximum zigzag stitch
width, screw the regulating screw (11) into the lever (1) and fix it in the
central position.
26 Service Instructions 52Xi, 52Xi-75 - 00.0 - 11/2021