Machine Skips Stitches; Fabric Does Not Feed; Fabric Does Not Feed Straight; Upper Thread Breaks At Start - Baby Lock BL-6800 Service Manual

PROBLEM CAUSE
Machine skips 1. Improper setting of the needle.
1.
stitches. 2. Bent or blunt needle.
3. Improper threading.
4. Improper combination of needle/ thread/fabric.
5. Stretch fabric is used.
6. Improper timing of the needle and rotary hook.
7. Improper height of the needle bar.
8. Improper clearance between the needle and rotary
Fabric does not 1. Stitch length is set at "0".
2.
feed 2. Improper height of feed dog.
.
3. Thick fabric.
4. Feed dog is worn out.
5. The feed dog is lowered.
Fabric does not 1. Uneven pressure on right/left side of presser foot.
3.
feed straight.
Upper thread 1. Improper threading.
4.
breaks at start.
5. Upper thread 1. Bent or blunt needle.
breaks during 2. Improper setting of needle.
sewing. 3. Thread tension is too tight.
4. Thread is tangled.
5. Inferior needle eye.
6. Inferior needle slot of needle plate.
7. Inferior upper thread path.
8. Inferior thread.
9. Needle hits needle plate or rotary hook.
10.There are scratches on inner rotary hook.
6. Upper thread 1. Fabric is pulled excessively.
breaks during 2. Improper use of reverse sewing button.
reverse sewing.
7. Lower thread 1. Lower thread tension is too tight.
breaks.
2. Too much thread is wound on bobbin.
3. Thread is tangled.
4. Bobbin does not turn in inner rotary hook.
5. Inferior thread.
hook.
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CORRECTION
1. Set the needle correctly.
2. Change the needle.
3. Reset threading correctly.
4. Select correct combination of
needle/ thread/fabric.
5. Use stretch fabric needle.
6. Refer to P.38.
7. Refer to P.39.
8. Refer to P.38.
1. Set proper stitch length.
2. Refer to P.43.
3. Change the fabric.
4. Change the feed dog.
5. Raise the feed dog with the
drop lever.
1. Change the presser foot and
the feed dog.
1. Thread correctly.
1. Change the needle.
2. Set the needle correctly.
3. Adjust tension control dial
correctly.
4. Thread correctly.
5. Change the needle.
6. Change the needle plate.
7. Clean or replace.
8. Check or change the thread.
9. Set the needle bar and rotary
hook correctly.
* Refer to P.38.
10.Change inner rotary hook.
1. Guide the fabric.
2. Push reverse sewing button
as far as it will allow.
1. Adjust the tension by
loosening the tension spring
screw on inner rotary hook.
2. Change to other bobbin or
adjust bobbin winder.
3. Thread correctly.
4. Change the bobbin.
5. Check or change the thread.