JUKI LK-1900AN Engineer's Manual page 31

Adjustment procedures
1. Turn the pulley by hand. When needle bar 1 has gone up,
adjust so that lower marker line 2 engraved on the needle bar
aligns with the bottom end of the needle bar bushing lower 3 .
2. Loosen setscrew 4 in the driver 9 . Open inner hook pressers
5 to the right and left, and remove inner hook presser 6 .
(Caution) At this time be careful not to let inner hook 7 come
off and fall.
3. Adjust so that the blade point of inner hook 7 aligns with the
center of needle 8 , and that a clearance of 0 mm is provided
between the front end of the driver 9 and the needle 8 as the
front end face of driver 9 receives the needle 8 to prevent the
needle from being bent. Then tighten setscrew 4 of the driver
9 .
4. Loosen setscrew !3 of the shuttle, and adjust the longitudinal
position of the shuttle. To do this adjustment, turn shuttle race
adjusting shaft !0 clockwise or counterclockwise to provide a
0.05 to 0.1 mm clearance between needle 8 and the blade
point of inner hook 7 .
5. After adjusting the longitudinal position of the shuttle, further
adjust to provide a 7.5 mm clearance between the needle 8
and the shuttle by adjusting the rotating direction. Then tighten
setscrew !3 of the shuttle.
(Caution) Apply a small amount of oil to race section !1 and
oil wick !2 , and use the sewing machine after an
extended period of disuse or cleaning the periphery
of hook portion.
Results of Improper adjustment
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