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WARNING :
Be extremely careful about the operation of the machine since the amount of oil has to be checked by
turning the hook at ahigh speed.
1-7. Hook oil amount (track of oil) adjustment
1) Check that the oil amount in the hook is proper
against the oil gauge.
2) Set the sewing machine at 4,000 sti/min referring to
"I-3-15. Break-in operation" p.12
, and make the
sewing machine run idle for about three minutes.
3) Place an oil amount checking paper in the specified
position while the sewing machine is in operation.
4) Check the oil amount (trace of oil) in five seconds.
(Confirm the time with your watch.)
(1) Sample of the correct oil amount (trace of oil)
1) The oil amount in the sample shown in the figure
on the left should be finely adjusted to increase/
decrease it properly. When finely adjusting the oil
amount, be careful not to excessively increase or
decrease it.
When the oil amount is too small = The hook may
be seized. (The hook may become hot.)
When the oil amount is too large = The sewing ma-
terial would be stained with oil.
2) The oil amount is checked on the condition that the
amount of oil on the three sheets of the oil amount
checking paper must be uniform.
(2) Adjusting the oil amount (trace of oil) in the
hook
1) Remove throat plate
1
. Turn oil amount adjust-
ment screw
2
in the “+” direction (direction
A
) to
increase the oil amount (tract of oil). Turn the screw
in the “–” direction (direction
B
) to decrease it.
2) After the oil amount is adjusted using oil amount
adjustment screw
2
, run the sewing machine idle
for approximately 30 seconds and confirm the oil
amount (tract of oil).
Oil amount
adjustment screw
2
Throat plate
1
A
B
①
Oil amount (track of oil) test paper
about 25 mm
about 70 mm
*
It is not necessary to be fussy about the paper quality.
②
Oil amount (track of oil) checking position
Approx. 3 to 5 mm
Hook
Hook driving shaft front bushing
Bed
Oil amount checking paper
*
Fit the oil amount checking paper to the underside
of the hook.
Lace surface
Approx. 2 mm
Proper amount (small amount)
Lace surface
Approx. 5 mm
Proper amount (large amount)
