HE-800C
11. TROUBLESHOOTING
79
Cause Check
Remedy
Page
Rotary
hook
Needle bar height and
needle bar lift amount
(The gauge is an option
part.)
1. Adjust the needle bar height to “1” on the gauge.
2. Adjust the needle and rotary hook timing to “2” on
the gauge.
65*
66*
Gap between the needle
and the tip of the rotary
hook
Adjust the gap between the needle and the rotary hook
tip to 0.01 - 0.08 mm. (Adjust to as large as possible
without causing skipped stitches to occur.)
* Move the needle bar to the left and right with your
finger, and check that the tip of the rotary hook does
not strike the needle.
67*
Rotary hook lubrication
・
Too small quantity of lubrication oil will cause thread
breakage. Adjust the quantity of lubrication oil.
・
The lubrication holes (1) between rotary hook and
rotary hook joint do not match up.
16*
*
Thread twisted around
rotary hook
Remove any twisted thread from the inner and rotary
hook.
63
Upper thread amount
Arm thread guide position
Adjust the arm thread guide position.
28
Bobbin case
Damaged outside of bobbin
case and bent bobbin
holder spring, etc.
Polish with buff or replace the part.
* Use the HE-800C bobbin case.
*
11-2. Skipped stitches
Items with a “*” in the “Page” column should only be handled by a qualified technician.
Cause Check
Remedy
Page
Needle
Needle facing
As viewed from the direction of the face plate, attach
needle so that the groove of the needle faces
frontward.
21
Needle installation height
Insert the end of the needle shank so that it touches the
top edge of the needle hole of the needle bar.
21
Bent needle
Replace needle.
21
Blunt needle tip or burr
Replace needle.
21
Thin needle
Use a needle with a count that matches the thread and
material.
–
Thread take-up spring Thread
take-up
spring
tension and height
Loosen the thread take-up spring tension or lower the
height to such a degree that does not cause double
hooking. Adjust it while checking bar tacking stitches.
28
(Continued on next page)
4894M
