Improper Lower Thread Winding Length - Toyota SD Service Manual

Troubleshooting

8.Improper lower thread winding length

[Example of phenomenon]
Step Item
Winding
amount of
1. Bobbin
lower
thread
Is the upper thread threaded on the thread guide?
Is the upper thread threaded on the lower thread guide?
Is the lower thread threaded properly through the bobbin
hole?
Diagnosing Method
<Condition>
Thread: Cotton yarn # 60
Wind-up: When the wound thread contacts
the bobbin stopper and the bobbin
stops
<Diagnosis>
Set the bobbin on the bobbin winder
shaft.
When the bobbin has returned to the
original position (to left) after winding up
the lower thread, measure the states of
winding (A, B).
A: Winding deviation
B: Winding amount
[Check item before adjustment]
A = 1.5 mm or less
B = 1.5 to 2.0 mm
22
Reference
Standard
Page
[Adjustment]
page.36