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42
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90˚
45˚
3-36 Adjusting the amount of oil in the hook
Adjusting procedure and points of the amount of oil in the hook
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Before adjustment ...
• Perform carefully to check the amount of oil since the hook is rotating at high speed.
• Perform adjusting the amount of oil at the sewing speed of 400 rpm.
• When adjusting and checking the amount of oil, remove bobbin, bobbin case, needle and needle thread
from thread take-up.
• Remove slide plate, and check the amount of oil using oil splash confirmation paper.
• If the machine has not been sufficiently warmed up for operation, make the machine run idle for approximately
three minutes. (Moderate intermittent operation)
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When the amount of oil is small, perform the adjustment from step 1) described below.
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When the amount of oil is much or you desire to slightly adjust the amount, perform the adjustment from step
3) described below.
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When adjusting the amount of oil to a small quantity (dotted line), perform the adjustment from step 1) described
below.
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Adjusting steps of the amount of oil in the hook
1) Tighten the oil amount adjustment screw until it will go no futrther to maximize the amount of oil, and
operate the machine for approximately 30 seconds in order to pull out a big quantity of oil, circulate oil to all
the lubricating routing including the hook, and stablize the oil path.
2) Loosen the oil amount adjustment screw by two turns and check the amount of oil. In this case, check the
amount of oil for five seconds after making the sewing machine run idle for approximately 30 seconds.
(Continuous operation for 35 seconds) Place the oil splash confirmation paper under the hook while the
sewing machine is operated.) (Refer to Fig. 2.)
3) Determine the turning amount of the oil amount adjustment screw from the amount of oil of this time
referring to (Fig. 1), adjust the amount of oil again, and check the amount of oil for five seconds after
making the sewing machine run idle for 30 seconds.
4) Adjust the position of the screw in the order of steps 2) to 3) until the appropriate amount of oil is obtained.
★
Cautions and points
(Note 1) When replacing the hook or for the machine head after an extended period of disuse (including
the new machine head), it takes approximately 10 to 20 seconds (at the sewing speed of 4,000
rpm) until oil comes out from the hook. Take care of seizure and adjust the number of revolution
at the start.
(Point 1) Perform the adjustment in the direction of squeeze (direction of loosening the screw), and more stable
adjustment can be performed.
(Point 2) Standard for adjustment is generally as follows :
• Standard position of the oil adjustment screw is in the range of loosening the screw by 2 to 3 turns
from the position where the screw is tightened until it will go no further.
• If the amount of oil is too much : Loosen the screw by 90˚ (1/4 turn).
• If the amount of oil is much : Loosen the screw by 45˚ (1/8 turn).
• When the adjustment is nearly completed, adjust the screw to such an extent of the length of slot of
the screw. When adjusting finely, take care not to excessively turn the screw since the amount of oil
changes even when slightly turning the screw.
Amount of oil is too
much.
(Point 3) Perform measuring the amount of oil at least three times, and check that the amount of oil is stabilized.
(Point 4) When adjusting the amount of oil, if the amount of oil is much before adjustment, operate the sewing
machine continuously for approximately one minute to discharge enough the oil adhered to the hook
and the remaining oil in oil path. Especially, be carefull when using the machine with a small quantity of
oil (dotted line).
(Point 5) When using the machine with a small quantity of oil (dotted line), perform checking the amount of oil
periodically since the hook is affected by dust of fabric or the like.
Amount of oil is
much.
Fine adjustment
of amount of oil
(Fig. 1) Standard for adjusting screw
Extent of slot
Decrease
Increase
