40
Trouble shooting guide
PROBLEM
PROBABLE CAUSE
CORRECTION
Upper thread
breaks
1. The machine is not threaded correctly.
2. The thread tension is too tight.
3. The thread is too thick for the needle
4. The needle is not inserted correctly.
5. The thread is wound around the spool holder pin.
6. The needle is damaged.
1. Rethread
the
machine.
2. Reduce the thread tension (lower number).
3. Select a larger needle.
4. Remove and reinsert the needle (flat side towards the back).
5. Remove the spool and wind thread onto spool.
6. Replace the needle.
Lower thread
breaks
1. The bobbin case is not inserted correctly.
2. The bobbin case is threaded incorrectly.
3. The lower thread tension is too tight.
1. Remove and reinsert the bobbin case and pull on the thread.
The thread should pull easily.
2. Check both bobbin and bobbin case.
3. Loosen lower thread tension as described.
Skipped stitches
1. The needle is not inserted correctly.
2. The needle is damaged.
3. The wrong size needle has been used.
4. The foot is not attached correctly.
1. Remove and reinsert needle (flat side towards the back).
2. Insert a new needle.
3. Choose a needle to suit the thread and fabric.
4. Check and attach correctly.
Needle breaks
1. The needle is damaged.
2. The needle is not correctly inserted.
3. Wrong needle size for the fabric.
4. The wrong foot is attached.
1. Insert a new needle.
2. Insert the needle correctly (flat side towards the back).
3. Choose a needle to suit the thread and fabric.
4. Select the correct foot.
Loose stitches
1. The machine is not correctly threaded.
2. The bobbin case is not correctly threaded.
3. Needle/fabric/thread
combination
is
wrong.
4. Thread
tension
wrong.
1. Check the threading.
2. Thread the bobbin case as illustrated.
3. The needle size must suit the fabric and thread.
4. Correct the thread tension.
Seams gather or
pucker
1. The needle is too thick for the fabric.
2. The stitch length is wrongly adjusted.
3. The thread tension is too tight.
1. Select a finer needle.
2. Readjust the stitch length.
3. Loosen the thread tension.
Uneven stitches,
uneven feed
1. Poor
quality
thread.
2. The bobbin case is wrongly threaded.
3. Fabric has been pulled.
1. Select a better quality thread.
2. Remove bobbin case and rethread and insert correctly.
3. Do not pull on the fabric while sewing, let it be taken up by
the machine.
The machine is
noisy
1. The machine must be lubricated.
2. Fluff or oil have collected on the hook or needle bar.
3. Poor quality oil has been used.
4. The needle is damaged.
1. Lubricate as described.
2. Clean the hook and feed dog as described.
3. Only use good quality sewing machine oil.
4. Replace the needle.
The machine jams
1. Thread is caught in the hook.
1. Remove the upper thread and bobbin case, turn the
handwheel backwards and forwards by hand and remove the
thread remnants. Lubricate as described.
