Troubleshooting - Singer F687C Instruction Manual

Troubleshooting

Thread Loops on Underside of Fabric
Possible cause:
Thread looping on the underside of the fabric is always an indication that the upper thread is not correctly
threaded. This happens when the upper thread is not correctly placed in the thread tension mechanism and
has not been threaded through the take up lever.
Solution: Rethread the machine, making sure to first raise the presser foot lifter before starting to thread, so thread
can be properly seated in the tension mechanism and take up lever. To know if you have rethreaded the
machine correctly, try this test:
• Raise the presser foot lifter (page 10) and thread the top of the machine (page 13).
• Thread the needle, but don't put the thread under the presser foot yet. As you pull the upper thread to
the left, it should pull freely.
• Put the presser foot lifter down. As you pull the upper thread to the left, you should feel resistance. This
means you are threaded correctly.
• Put the thread under the presser foot, and then draw up the bobbin thread. Slip both thread tails under
the presser foot towards the back. Lower the presser foot and begin sewing.
If you put the presser foot lifter down, but the thread still pulls freely (you feel no difference whether the
presser foot is up or down), this means that you have threaded incorrectly. Remove the upper thread and
rethread the machine.
Bobbin Thread Breaking
Possible cause:
Bobbin threaded incorrectly.
Solution: Check that bobbin is placed correctly in the bobbin holder (page 12).
Possible cause: Bobbin wound too full or unevenly.
Solution:
Bobbin thread may not have been correctly placed into bobbin winding tension disc during the bobbin
winding process (page 12).
Possible cause: Dirt or lint in bobbin holder.
Solution: Clean bobbin holder (page 34).
Possible cause: Wrong bobbins being used.
Solution:
Use bobbins that are the same style as those that come with the machine (SINGER® Class 15 transparent
bobbins) – don't substitute.
Bobbin Thread Showing on Top of Fabric
Possible cause: Top thread too tight.
Solution:
Reduce upper thread tension (page 16).
Possible cause:
Thread path is obstructed, putting extra tension on top thread.
Solution:
Check that the top thread path is not obstructed and thread is moving freely through the thread path.
Possible cause:
Bobbin thread not in bobbin case tension.
Solution: Rethread bobbin (page 12).
Bobbin Winding Difficulties
Possible cause:
Bobbin thread loosely wound on bobbin.
Solution: Rewind bobbin, making sure that the thread is placed snuggly in the bobbin winding tension disc (page
12).
Possible cause:
Bobbin winding spindle not fully engaged, therefore bobbin not winding.
Solution: Check that the bobbin winding spindle has been fully engaged before starting to wind.
Maintenance – 35
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