Performance Checklist; General Problems - Singer 8748 Manual De Instrucciones

5. PERFORMANCE CHECKLIST

GENERAL PROBLEMS

Machine does not sew.
* Power switch is turned off.- Turn on the switch.
* Buttonhole lever is not raised when sewing stitch patterns.
– Raise buttonhole lever.
* Buttonhole lever is not lowered when sewing buttonhole.
– Lower buttonhole lever.
* Bobbin winder is engaged. – Disengage bobbin winder (see
page 14 - 15).
* Presser foot is not lowered - Lower presser foot.
Machine jams/knocks.
* Thread is caught in hook.- Clean hook (see page 50 - 51).
* Needle is damaged.- Replace needle (see page 23).
Fabric does not move.
* Presser foot is not lowered - Lower presser foot.
* Stitch length is too short - Lengthen stitch length.
* Feed dogs are lowered - Raise feed dogs.
STITCHING PROBLEMS
Machine skips stitches.
* Needle is not all the way up into needle clamp(see page 23).
* Needle is bent or blunt. - Replace needle (see page 23).
* Machine is not threaded correctly (see page 18 - 19).
* Thread is caught in hook. - Clean hook (see page 50 - 51).
Stitches are irregular.
* Needle size is not correct for thread and fabric (see page 22).
* Machine is not threaded correctly (see page 18 - 19).
* Top thread tension is too loose (see page 24 - 25).
* Fabric is being pulled or pushed against machine feeding
action. - Guide it gently.
* Bobbin has not been wound evenly. - Rewind bobbin.
Needle breaks.
* Fabric is being pulled or pushed against machine feeding
action. - Guide it gently.
* Needle size is not correct for thread and fabric (see page 22).
* Needle is not all the way up into the needle clamp (see page
23).
* Twin needle is being used but stitch width is set too wide (see
page 52 - 53).
THREAD PROBLEMS
Thread bunches.
* Top and bobbin threads are not drawn back under presser
foot before starting seam. - Draw both threads back under
presser foot about 6 inches (10 cm) and hold until a few
stitches are formed.
Needle thread breaks.
* Machine is not threaded correctly (see page 18 - 19).
* Top thread tension is too tight (see page 24 - 25).
* Needle is bent. - Replace needle (see page 23).
* Needle size is not correct for thread and fabric (see page 22).
Bobbin thread breaks.
* Bobbin case is not threaded correctly (see page 16 - 17).
* Lint accumulates in bobbin case or hook.
- Remove lint (see page 50 -51).
Fabric puckers.
* Top thread tension is too tight.
- Adjust thread tension (see page 24 - 25).
* Stitch length is too long for sheer or soft fabric.
- Shorten stitch length.
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