Brother DH4-B980 Sewing Machine User Manual


 
11. TROUBLESHOOTING
RH-9800
58
11. TROUBLESHOOTING
If there is a problem with operation, first check that the threads are correctly threaded and that the needle is correctly
installed.
CAUTION
Turn off the power switch and disconnect the power cord before carrying out troubleshooting, otherwise the
machine will operate if the start switch is pressed by mistake, which could result in injury.
MACHINE HEAD
Problem Cause Remedy Page
Thread tension control nut
pressure is too strong.
Adjust to an appropriate pressure. 32
Thread is of poor quality. Use a better-quality thread.
Thread is too thick for the needle. Use a differently-size needle.
Needle groove or needle hole are
not smooth.
Replace with a new needle. 16
Needle and looper adjustment is
incorrect.
Adjust the needle bar height or
the looper and spreader height.
43
Thread breaks.
Needle, looper, throat plate or
thread path is damaged.
Repair the damage with an
oilstone or buffer, or replace the
damaged part.
Thread tension control nut
pressure is too strong or too
weak.
Adjust to an appropriate pressure.
32
Needle point is broken or bent. Replace with a new needle. 16
Needle and looper adjustment is
incorrect, or clearance is incorrect.
Adjust correctly. 44
Needle and needle guard
adjustment is incorrect.
Adjust correctly.
47
Skipped stitches occur.
Looper tip is blunt.
Repair with an oilstone or replace
the looper with a new one.
Needle is bent. Replace with a new needle. 16
Needle and looper adjustment is
incorrect.
Adjust the needle bar height or
the looper and spreader height.
43
Needle breaks.
Needle and needle guard
adjustment is incorrect.
Adjust correctly. 47