Alfa 4760 Livret D'instructions page 93

Troubleshooting
Condition
The needle thread
breaks.
The bobbin thread
breaks.
The needle breaks.
The needle thread
loops.
Skipped stitches
Seam puckering
The cloth is not fed
smoothly.
The machine does not
work.
Patterns are distorted.
The buttonhole is not
sewn well.
Noisy operation
1. The needle thread is not threaded properly.
2. The needle thread tension is too tight.
3. The needle is bent or blunt.
4. The needle is incorrectly inserted.
5. The needle thread and the bobbin thread are not set
properly under (drawn to the rear of) the presser foot
when sewing is starting.
6. The fabric is not drawn to the rear when sewing is
finished.
7. The thread is too heavy or too fine for the needle.
1. The bobbin thread is not threaded properly in the
bobbin holder.
2. Lint has collected in the bobbin holder.
3. The bobbin is damaged and doesn't turn smoothly.
4. The thread is wound loosely on the bobbin.
1. Needle is incorrectly inserted.
2. The needle is bent or blunt.
3. The needle clamp screw is too loose.
4. A proper foot is not used.
5. The fabric is not drawn to the rear when sewing is
finished.
6. The needle is too fine for the fabric being sewn.
1. The needle thread tension is too loose.
2. The needle size is not suitable for the thread.
1. The needle is incorrectly inserted.
2. The needle is bent or blunt.
3. The needle and/or thread are not suitable for the
fabric being sewn.
4. A blue needle is not being used for sewing stretch,
very fine fabrics and synthetics.
5. The needle thread is not threaded properly.
6. A poor quality needle is used.
1. The needle thread tension is too tight.
2. The needle thread is not threaded properly.
3. The needle is too heavy for the fabric being sewn.
4. The stitch length is too long for the fabric.
* Use a stabilizer for very fine fabrics.
1. The feed dog is packed with lint.
2. The stitches are too fine.
3. The feed dog was not raised after being lowered.
1. The machine is not plugged in.
2. Thread is caught in the hook race.
3. The bobbin winder spindle is still in the winding position.
1. The stitch is not balanced.
1. The stitch density is not suitable for the fabric being
sewn.
2. Interfacing is not being used with stretch fabrics.
1. The feed dog is packed with lint.
2. Lint has collected in the bobbin holder.
Cause
89
Reference
Page 30
Page 18
Page 20
Page 20
Page 36
Page 36
Page 20
Page 28
Page 84
Replace the bobbin
Re-wind the bobbin.
Page 20
Page 20
Page 20
Use proper foot.
Page 36
Page 20
Page 18
Page 20
Page 20
Page 20
Page 20
Page 20
Page 30
Replace the needle
Page 18
Page 30
Page 20
Make stitch shorter
Page 84
Make stitch longer
Page 16
Page 8
Page 84
Page 26
Page 82
Page 54
Page 48
Page 84
Page 84