4. ADJUSTMENT
HE-800A
101
4-20. Adjusting the upper thread feeding amount
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.
4-21. Adjusting the feed timing belt
1. Remove the bolt (1) and the nut (2).
2. Loosen the three screws (3) so that the feed pulse motor (4) moves easily.
3. While using a spring gauge to push the notch in the motor mounting bracket (5) with a force of 98 N, tighten the
screws (3).
4. Check that the timing belt (6) moves smoothly.
5. Gently tighten the bolt (1) and the nut (2).
* If you do not have a spring gauge, adjust the tension with the bolt (1) and the nut (2) so that the amount of belt
deflection is approximately 3.5 mm when a force of 5 N is applied in the middle of the belt span. Then tighten the
three screws (3).
4360Q
4362Q
4359Q
4361Q