DURKOPP ADLER 171 Operating Instructions Manual page 99

Troubleshooting
Operating Instructions 171/173 - 02.0 - 09/2019
Error Possible causes
Missing Needle thread and looper
stitches thread have not been
threaded correctly
Needle is blunt or bent
Needle is not inserted
correctly into the needle
bar
The needle thickness used
is unsuitable
The reel stand is installed
incorrectly
Thread tensions are
too tight
Throat plate, looper or
spread have been
damaged by the needle
Loose stitches Thread tensions are not
adjusted to the sewing
material, the sewing
material thickness or the
thread used
Needle thread and looper
thread have not been
threaded correctly
Needle Needle thickness is
breakage unsuitable for the sewing
material or the thread
Remedial action
Check threading path
Replace the needle
Insert the needle correctly
into the needle bar
Use recommended needle
thickness
Check the assembly of
the reel stand
Check thread tensions
Have parts reworked by
qualified specialists
Check thread tensions
Check threading path
Use recommended needle
thickness
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