Problem
Cause
Correction
Upper thread breaks
Lower thread breaks
Skipped stitches
Needle breaks
Loose stitches
Seams gather or pucker
Uneven stitches, uneven feed
The machine is noisy
The machine jams
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 round wound the spool holder pin
6. The needle is damaged
1. The bobbin case is not inserted correctly
2. The bobbin case is threaded wrongly
3. The lower thread tension is too tight
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. 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. 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. The needle is too thick for the fabric
2. The stitch length is wrongly adjusted
3. The thread tension is too tight
1. Poor quality thread
2. The bobbin case is wrongly threaded
3. Fabric has been pulled
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
Thread is caught in the hook
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 reel and wind thread onto reel
6. Replace the needle
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
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
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
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
1. Select a finer needle
2. Readjust the stitch length
3. Loosen the thread tension
1. Select a better quality thread
2. Remove bobbin case and retread and insert correctly
3. Do not pull on the fabric while sewing, let it be taken up by the machine
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
Remove the upper thread and bobbin case, turn the handwheel
backwards and forwards by hand and remove the thread remands.
Lubricate as described
49
Trouble shooting guide
Summary of Contents for 8660
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