Lervia KH 4001, Operating Instructions Manual

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Troubleshooting
If you should find yourself confronted with any problems during sewing, first consult the respective section of the user manual, which will provide you with
further details relating to the specific operating procedure. By comparing the given details you can ensure that you are operating the machine correctly
and appropriately. If a problem cannot be prevented or rectified in this way, the following procedure could provide assistance in regard to the detection
of operational, installation and machine defects and faults as well as being an aid to trouble shooting.
Contact your nearest specialialist on sewing machines if the difficulties cannot be remedied.
Problem Cause Solution
Upper thread is breaking
• Upper thread is incorrectly inserted.
• Upper thread tension is too tight
• Upper thread „matted” (tangled).
• Spool of thread incorrectly inserted-/fitted.
• Needle is bent/blunt.
• Inappropriate combination of needle size/strength
of thread.
• Thread the upper thread correctly!
• Loosen the upper thread tension a little!
• Thread the upper thread once again!
• Insert the spool of thread once again!
• Change the needle!
• Check the combination needle size/strength of
thread!
Lower thread is breaking
• Upper thread „matted” (tangled).
• Fault in run of thread at the spool in the gripper.
• Tension of lower thread is too tight.
• Lower thread is not inserted. • Thread the upper thread once again!
• Insert the spool correctly once again!
• Loosen the low thread tension a little!
• Insert the low thread correctly once again!
Stitches are omitted
• Needle inserted incorrectly.
• Inappropriate combination of needle size/strength
of thread.
• Dust adhering to the stitch plate a on the bottom.
• Sewing garn incorrectly inserted/threaded.
• Insert the needle correctly!
• Check the combination, needle size/strength
of thread!
• Clean the sewing machine!
• Thread the sewing garn correctly!
Loops and tangles in the seam • Wrong adjustment of the thread tension. • Readjust the thread tension!
Material is rippled in the vicinity
of the seam
• Thread tension is too tight on the rippled side.
• Thread run on the machine is wrong.
• An unsuitable needle has been used.
• Inappropriate combination of needle size/strength
of thread.
• Readjust the thread tension!
• Check the thread run and thread the needle correctly!
• Use the matching needle!
• Check the combination needle
size/strength of thread!
The material is not being fed correctly
• Stitch length selector 6 set at „no feed”.
• Inappropriate combination needle size/
strength of thread.
• Thread is matted (tangled).
• The darning plate is installed on top of the stitch
plate a .
• Set the stitch length selector 6 at the required stitch
length (feed)!
• Check the combination needle size/strength of
thread!
• Thread the upper thread once again!
• Remove the darning plate!
Needle keeps breaking
• Needle inserted incorrectly.
• Inappropriate combination of needle
size/strength of thread.
• You are pulling
the fabric.
• Insert the needle correctly!
• Check the combination needle size/strength of
thread!
• Only allow the material to be tranported by the
feed dog!
Machine is running noisily or slowly
• Dust adhering to the stitch plate a on the bottom.
• Machine is inadequately lubricated.
• Clean the sewing machine!
• Lubricate the sewing machine!
Machine does not start up
• The power plug k is not connected to the power
supply.
• Power switch r of the machine is set at „OFF” („0”).
• Foot control has not been pressed down properly.
• Coupling disconnector on the handwheel
0 is set
at „Spool wind”.
• Insert the power plug k into
a wall socket!
• Set the power switch r at „ON” („I”)!
• Apply more pressure to the foot control!
• Do not forget to press
in the handwheel 0 !
IB_KH4001_E2719_GB_LB3-6 22.04.2008 15:23 Uhr Seite 17