Table 4-4.—Troubleshooting Chart
A. Troubleshooting Chart
Trouble
Probable Cause
Remedy
T H R E AD
Thread controller
Adjust spring tension and/or spring stop.
B R E A K A GE
Right twist thread
Change to left twist (Z).
Hook point piercing needle thread
Adjust thread controller spring stop.
Needle eye too small
Select larger size.
Burr on needle point
Remove burr or replace needle.
.
Too much tension
Adjust tension springs.
Improper threading sequence
Rethread (check first).
Thread unwinding incorrectly
Adjust stand and/or spool.
Thread breaks when clearing work
Adjust tension release. Thread take-up
lever not at highest point.
S K I P P ED
Needlebar
improperly
set
S T I T C H ES
Needle not all the way into
Needle incorrectly aligned
Reset.
b ar
Insert correctly.
Insert correctly.
Thread too large large for needle
Select correct needle.
eye
Presser bar maladjusted
Adjust presser bar.
T H R E AD
Operating machine without ma-
Unthread when running without fabric.
J A M M I N G
terial
U N D ER
T H R O AT
Failure to hold free ends of thread
Maintain pressure.
P L A T E
for first stitches
Needle thread not between tension
Thread disc.
discs.
U P P ER
Feed-driving eccentric improperly
Adjust eccentric.
T H R E AD
adjusted
L O O P I NG
U N D ER
No upper thread tension
Adjust or place thread in tension disc.
M A T E R I AL
4-12
