Performance Checklist - Singer 8770 CURVY Instruction Manual

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.
Machine jams/knocks.
* Thread is caught in hook.- Clean hook (see page 80 - 81).
* Needle is damaged.- Replace needle (see page 24 - 25).
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.
Desired pattern cannot be selected.
* Twin needle mode switch has been turned on and lit red.
– Turn off the switch.
STITCHING PROBLEMS
Machine skips stitches.
* Needle is not all the way up into needle clamp. - See page
24 - 25.
* Needle is bent or blunt. - Replace needle (see page
24 - 25).
* Machine is not threaded correctly. - See page 20 - 21.
* Thread is caught in hook. - Clean hook (see page 80 - 81).
Stitches are irregular.
* Needle size is not correct for thread and fabric. - See page
24 - 25.
* Machine is not threaded correctly. - See page 20 - 21.
* Top thread tension is too loose. - See page 26 - 27.
* 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
24 - 25.
* Needle is not all the way up into the needle clamp. - See page
24 - 25.
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 4 inches (10 cm) and hold until a few
stitches are formed.
Needle thread breaks.
* Machine is not threaded correctly. - See page 20 - 21.
* Top thread tension is too tight. - See page 26 - 27.
* Needle is bent. - Replace needle (see page 24 - 25).
* Needle size is not correct for thread and fabric - See page
24 - 25.
Bobbin thread breaks.
* Bobbin case is not threaded correctly. - See page 18 - 19.
* Lint accumulates in bobbin case or hook. - Remove lint
(see page 80 - 81).
Fabric puckers.
* Top thread tension is too tight. - Adjust thread tension
(see page 26 - 27).
* Stitch length is too long for sheer or soft fabric. - Shorten
stitch length.
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