7. ADJUSTMENT
7-18. Adjusting the upper thread feeding amount
Decrease
0753D
1. Loosen the screw (1), and then turn the tension take-up lever (2) to adjust the upper thread feeding amount.
2. Move the trimmer driving arm (3) by hand and check that upper thread feeding is completed before the upper thread is cut.
Note: If the above adjustment is not made, it may result in the upper thread pulling out or in upper thread clamping errors.
7-19. Adjusting the rotary hook lubrication
4364Q
1. Remove the rubber cap (1).
2. Turn the adjusting screw (2) to adjust the lubrication amount.
* Adjust so that approximately 10 drops of oil are released when the sewing machine is run at a speed of 4,000 rpm for
three cycles to sew about 114 stitches. Use Kraft paper (3) or similar to catch the oil drops. As a guide, the optimum
position can be obtained if the adjusting screw (2) is tightened as much as possible and then loosened about two turns.
* Furthermore fine adjustments can then be made using the rotary hook joint screw (4).
* If the lubrication amount has been reduced, run the machine for 200 - 300 sewing cycles and then check it again.
Note: If lubrication stops, it will cause problems such as rotary hook seizure and thread breakages.
109
Increase
More
Less
More
Less
HE-800B
1792B
4365Q
To oil tank
4366Q