14. TROUBLESHOOTING

 

Problem

 

 

 

Possible cause

Page

9

Lower thread is tangled at

 

Is the bobbin spinning direction correct when the lower thread is

 

 

the sewing start.

 

 

being pulled?

Instruction

 

Spinning of bobbin during

 

 

Set the bobbin so that it turns in the opposite direction to the

manual

 

thread trimming

 

 

rotary hook.

 

 

 

 

Is there too much thread

 

 

 

 

 

wound onto the bobbin?

Instruction

 

 

 

 

The bobbin winding amount

 

 

 

 

should not be more than

manual

 

 

 

 

80 %.

 

 

Instruction

 

Lower

 

Is the anti-spin spring attached? (8560A)

 

 

 

Attach the anti-spin spring.

manual

 

thread

 

 

 

 

Is the bobbin turning smoothly?

 

 

 

 

 

 

 

 

 

If the bobbin is not turning smoothly, replace the bobbin.

 

 

 

 

Is a bobbin other than the light-alloy bobbins specified by Brother

Instruction

 

 

 

 

being used? (8560A)

 

0628M

 

 

Use only bobbins which are specified by Brother.

manual

 

 

 

 

3557M

 

 

 

 

 

 

 

 

 

10

Upper and lower threads

 

Is the needle bent or is the needle tip broken?

 

 

are breaking.

 

 

Replace the needle if it is bent or broken.

Instruction

 

 

 

Is the needle properly installed?

 

 

 

 

If it is incorrect, install the needle correctly.

manual

 

 

 

Is the machine properly threaded?

Instruction

 

 

 

 

If it is incorrect, thread the thread correctly.

manual

 

 

 

Is the rotary hook sufficiently lubricated?

Instruction

 

 

 

 

If the oil gauge is down to the lower reference line in the oil

 

 

 

 

gauge window, add more oil.

manual

 

 

 

Is the upper or lower thread tension too weak or too strong?

Instruction

 

 

 

 

Adjust the upper thread or lower thread tension.

manual

 

 

 

Is the upper thread may be loose because the thread take-up

 

 

 

 

 

spring operating range is too small?

69

 

 

 

 

Adjust the position of the thread take-up spring.

 

 

 

Is the needle and rotary hook timing incorrect?

73

 

 

 

 

Adjust the height of the needle bar.

 

 

 

 

Adjust the clearance between the needle and the rotary hook.

76 - 77

 

 

 

Is the thread too thick for the needle?

 

 

 

 

 

Use the correct needle or the correct thread.

 

 

 

 

Is the rotary hook, bobbin case, thread take-up lever or some other

 

 

 

 

 

part in the thread path damaged?

 

 

0471M

 

 

Repair the damage, or replace the part with a new one.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

11

Broken needles

 

Is the material being pushed or pulled with excessive force during

 

 

 

 

 

sewing?

Instruction

 

 

 

Is the needle properly installed?

 

 

 

 

If it is incorrect, install the needle correctly.

manual

 

 

 

Is the needle bent, is the needle tip broken, or is the needle hole

 

 

 

 

 

blocked?

 

 

 

 

 

Replace the needle.

 

 

 

 

Is the needle and rotary hook timing incorrect?

73

 

 

 

 

Adjust the height of the needle bar.

 

 

 

 

Adjust the clearance between the needle and the rotary hook.

76 - 77

 

 

 

 

Caution

 

 

 

 

 

 

 

extremely dangerous to leave any pieces of broken

 

 

 

 

 

 

 

 

 

 

 

 

It is

 

 

 

 

 

 

needle sticking in the material. If the needle breaks,

 

 

 

 

 

 

search for all pieces until the whole of the needle is

 

 

 

 

 

 

found again.

 

 

 

 

 

 

Furthermore, we recommend that through steps be

 

 

 

 

 

 

taken to account for such needles to comply with

 

 

 

0469M

 

 

product liability regulations.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Z-8550A, 8560A

112