JUKI LU-1510N-7 Quick start guide

29340700
No.E337-04
ENGINEER’S MANUAL
®
1-NEEDLE, UNISON FEED, LOCKSTITCH MACHINE
(AUTOMATIC LUBRICATION)
LU-1510N
1-NEEDLE, UNISON FEED, LOCKSTITCH MACHINE WITH AUTOMATIC THREAD TRIMMER
(AUTOMATIC LUBRICATION)
LU-1510N-7, LU-1511N-7
1-NEEDLE, UNISON FEED, LOCKSTITCH MACHINE WITH AUTOMATIC THREAD TRIMMER
(SPECIFICATION FOR LIGHT-WEIGHT MATERIALS)•(AUTOMATIC LUBRICATION)
LU-1510NA-7
1-NEEDLE, UNISON FEED, LOCKSTITCH MACHINE
LU-1508N, LU-1509N
1-NEEDLE, UNISON FEED, LOCKSTITCH MACHINE (FOR EXTRA HEAVY-WEIGHT MATERIALS)
LU-1508NH, LU-1509NH
2-NEEDLE, UNISON FEED, LOCKSTITCH MACHINE (AUTOMATIC LUBRICATION)
LU-1560N, LU-1561N
2-NEEDLE, UNISON FEED, LOCKSTITCH MACHINE WITH AUTOMATIC THREAD
TRIMMER (AUTOMATIC LUBRICATION)
LU-1560N-7, LU-1561N-7
2-NEEDLE, UNISON FEED, LOCKSTITCH MACHINE WITH ORGANIZED SPLIT NEEDLE BAR
LU-1565N

PREFACE
This Engineer’s Manual is written for the technical personnel who are responsible for the service and maintenance
of the machine.
The Instruction Manual for these machines intended for the maintenance personnel and operators at an apparel
factory contains operating instructions in detail. And this manual describes “Standard Adjustment”, “Adjustment
Procedures”, “Results of Improper Adjustment”, and other important information which are not covered in the
Instruction Manual.
It is advisable to use the relevant Instruction Manual and Parts List together with this Engineer’s Manual when
carrying out the maintenance of these machines.
This manual gives the “StandardAdjustment” on the former page under which the most basic adjustment value is
described and on the latter page the “Results of Improper Adjustment” under which stitching errors and troubles
arising from mechanical failures and “How ToAdjust” are described.

CONTENTS
1. SPECIFICATIONS.......................................................................................... 1
2. STANDARD ADJUSTMENT ...........................................................................8
(1) Needle entry position.................................................................................................8
(2) Longitudinal position of the feed dog ......................................................................8
(3) Lateral position of the feed dog..............................................................................10
(4) Height of the feed dog .............................................................................................10
(5) Height of the hook....................................................................................................12
(6) Adjusting the inner hook guide ..............................................................................12
(7) Needle-to-hook timing .............................................................................................14
(8) Lift of the presser foot .............................................................................................16
1) Hand lifter .........................................................................................................................................16
2) Knee lifter (Without thread trimmer only) ..........................................................................................16
3) Automatic presser foot lifter (Machine with thread trimmer only)......................................................18
(9) Timing between the upper shaft and the lower shaft............................................18
(10) Feed cam timing .......................................................................................................20
1) Horizontal feed cam timing ...............................................................................................................20
2) Top feed cam timing..........................................................................................................................22
(11) Feed motion ..............................................................................................................24
1) Amount of alternate vertical movement (position of the vertical adjusting arm) ...............................24
2) Alternate momentum ........................................................................................................................26
(12) Needle sway (Adjusting the bottom feed amount)................................................26
(13) Stitch length of forward/reverse feed .....................................................................28
(14) Balancer (Machine without thread trimmer only) ..................................................28
(15) Vertical position of the needle bar rocking frame .................................................30
(16) Dimension of the needle stop adjusting slide shaft (asm.) ..................................32
(17) Position of the change lever....................................................................................32
(18) Position of the reverse feed control lever..............................................................34
(19) Safety clutch .............................................................................................................34
(20) Reverse feed cylinder ..............................................................................................36
(21) Lubrication ................................................................................................................36
1) In case of manual lubrication ............................................................................................................36
2) In case of automatic lubrication ........................................................................................................38
(22) Thread trimmer device .............................................................................................40
1) Position of the counter knife and the clamp spring ...........................................................................40
2) Position of the counter knife base.....................................................................................................42
3) Vertical position of the moving knife .................................................................................................42
4) Adjusting the knife pressure .............................................................................................................44
5) Thread trimmer cam .........................................................................................................................44
6) Thread trimmer cam timing...............................................................................................................46
7) Connecting the rocking arm and the thread trimmer roller arm ........................................................46
8) Connecting the left and right rocking arms (2-needle machine only) ..............................................48
9) Thread trimmer solenoid...................................................................................................................48
(23) Alternate vertical dial ...............................................................................................50
1) Installing position of the detection switch of the amount of alternate vertical movement .................50

3. INSTALLATION OF THE OPTIONAL PARTS ..............................................52
(1) DL device (For the machine with thread trimmer only) ..........................................52
(2) Thread trimmer Ver.UP set
(Part No. for 1-needle : 21389259, Part No. for 2-needle : 21389267) ....................53
(3) Bobbin thread remaining amount detecting device
(AE-10A Kit Part No. : GAE10000AA0) .....................................................................53
(4) Automatic reverse feed device .................................................................................54
1) Removing the window plate (Removing parts list).............................................................................54
2) Removing the reverse feed control lever (Removing parts list).........................................................54
3) Installing the reverse feed link hinge screw (List 1)...........................................................................54
4) Installing the reverse feed control lever (List 2).................................................................................55
5) Installing the automatic reverse feed device (List 3) .........................................................................56
6) Installing the touch-back switch (List 4).............................................................................................57
7) Installing the pneumatic components (List 5) ....................................................................................57
(5) Automatic presser foot lifter ...................................................................................58
1) Installing the automatic presser foot lifter (List A)..............................................................................58
2) Installing the pneumatic device components.....................................................................................59
3) Parts List............................................................................................................................................60
4. PORTION TO WHICH LOCKTITE IS APPLIED .......................................... 61
5. SELECTIVE PARTS AND CONSUMABLE PARTS..................................... 62
6. ENGRAVED MARKER DOTS ON THE HANDWHEEL
(FOR THE MACHINE WITH THREAD TRIMMER ONLY) ........................... 63
7. LUBRICATION ROUTE DIAGRAM.............................................................. 63
8. MACHINE HEAD WIRING
(FOR THE MACHINE WITH THREAD TRIMMER ONLY) ............................64
(1) Connectors coming from machine head..................................................................64
(2) Connectors coming from pneumatic device............................................................65
(3) Connectors coming from the relay cable (Connecting side to the control box) .......66
9. TABLE OF TROUBLES AND CORRECTIVE MEASURES......................... 67
(1) With regard to sewing ................................................................................................67
(2) With regard to thread trimming.................................................................................71
10. DRAWING OF THE TABLE ........................................................................ 75

– 1 –
No. Item Specifications
1Model LU-1510N (Standard gauge type)
2Model name 1-needle, unison feed, lockstitch machine (automatic lubrication)
3Application For heavy-weight materials
4Sewing speed Max. 2,500 rpm
5Needle SCHMETZ 135 X 17 Nm 125 to 180 Standard : Nm 160
Applicable thread size
for sewing
7 Stitch length Max. 9 mm (forward/reverse feed)
8Presser foot lift Hand lifter : 9 mm Knee lifter : 16 mm
Stitch length adjusting
mechanism
Reverse stitch adjusting
method
11 Thread take-up Slide thread take-up
12 Needle bar stroke 36mm
2.5mm to 6.5mm
Alternate foot stroke adjusted by long hole
14 Hook Vertical-axis 2-fold hook (Latch type)
15 Feed mechanism Box feed
Top and bottom feed
actuation mechanism
17 Lubrication Automatic lubrication (partially by manual)
18 Lubricating oil JUKI New Defrix Oil No. 2 (equivalent to ISO standard VG32)
19 Bed size 517 mm x 178 mm
20 Space under the arm 255mm x99mm
21 Hand wheel size V belt effective diameter : ø93.3 mm Outer diameter : ø160 mm
22 Motor 2P, 400W, 4P,400W
1. SPECIFICATIONS
6#30 to #5
9By dial
10 By level
13 Alternate foot stroke
16 Timing belt

– 2 –
No. Item Specifications
1Model LU-1510N-7 (Standard gauge type)
LU-1511N-7 (LU-2210 gauge type)
2Model name 1-needle, unison feed, lockstitch machine with automatic thread trimmer (automatic lubrication)
3Application For heavy-weight materials
4Sewing speed Max. 3,000 rpm
5Needle SCHMETZ 135 X 17 Nm 125 to 180 Standard : Nm 160
Applicable thread size
for sewing
Applicable thread size
to be cut
8 Stitch length Max. 9 mm (forward/reverse feed)
9 Presser foot lift Hand lifter : 9 mm Automatic presser foot lifter : 16 mm
Stitch length adjusting
mechanism
Reverse stitch adjusting
method
12 Thread take-up Slide thread take-up
13 Needle bar stroke 36 mm
1 mm to 6.5 mm
Alternate foot stroke adjusted by dial
15 Hook Vertical-axis 2-fold hook (Latch type)
16 Feed mechanism Box feed
Top and bottom feed
actuation mechanism
Thread trimming
method
19 Lubrication Automatic lubrication (partially by manual)
20 Lubricating oil JUKI New Defrix Oil No. 2 (equivalent to ISO standard VG32)
21 Bed size 517 mm x 178 mm
22 Space under the arm 255 mm x 99 mm
23 Hand wheel size V belt effective diameter : ø93.3 mm Outer diameter : ø160 mm
24 Motor SC-510
6#30 to #5
7#30 to #5
10 By dial
11 Air cylinder type (with touch-back switch)
14 Alternate foot stroke
17 Timing belt
18 Cam-driven scissors type

– 3 –
No. Item Specifications
1Model LU-1510NA-7 (Specification for light-weight materials)
1-needle, unison feed, lockstitch machine with automatic thread trimmer
(specification for light-weight materials) (automatic lubrication)
3Application For heavy-weight•light-weight materials
4Sewing speed Max. 2,000 rpm
5 Needle SCHMETZ 135 X 17 Nm 90 to 140 Standard : Nm 120 (#19)
Applicable thread size
for sewing
Applicable thread size
to be cut
8Stitch length Max. 7 mm (forwardl/reverse feed)
9 Presser foot lift Hand lifter : 7 mm Automatic presser foot lifter : 16 mm
Stitch length adjusting
mechanism
Reverse stitch adjusting
method
12 Thread take-up Slide thread take-up
13 Needle bar stroke 38 mm
14 Alternate foot stroke 1 mm to 6.5 mm
Alternate foot stroke adjusted by dial
15 Hook Vertical-axis 2-fold hook (Latch type)
16 Feed mechanism Box feed
Top and bottom feed
actuation mechanism
Thread trimming
method
19 Lubrication Automatic lubrication (partially by manual)
20 Lubricating oil JUKI New Defrix Oil No. 2 (equivalent to ISO standard VG32)
21 Bed size 517 mm x 178 mm
22 Space under the arm 255 mm x 99 mm
23 Hand wheel size V belt effective diameter : ø93.3 mm Outer diameter : ø160 mm
24 Motor SC-510
6#30 to #5
7#30 to #5
2Model name
10 By dial
11 Air cylinder type (with touch-back switch)
17 Timing belt
18 Cam-driven scissors type

– 4 –
No. Item Specifications
1Model LU-1508N (Standard gauge type) LU-1508NH (Standard gauge type)
LU-1509N (LU-2210 gauge type) LU-1509NH (LU-2210 gauge type)
2Model name 1-needle, unison feed, lockstitch 1-needle, unison feed, lockstitch machine
machine (For extra heavy-weight materials)
3 Application For heavy-weight materials For extra heavy-weight materials
4Sewing speed Max. 2,500 rpm Max. 2,000 rpm
5 Needle SCHMETZ 135 X 17 SCHMETZ 190R
Nm 125 to 180 Nm 125 to 180
Standard : Nm 160 Standard : Nm 160
Applicable thread size
for sewing
7 Stitch length Max. 9 mm (forward/reverse feed) Max. 10 mm (forward/reverse feed)
8Presser foot lift Hand lifter : 9 mm Knee lifter : 16 mm
Stitch length adjusting
mechanism
Reverse stitch adjusting
method
11 Thread take-up Slide thread take-up
12 Needle bar stroke 36 mm 38 mm
13 Alternate foot stroke 2.5 mm to 6.5 mm
Alternate foot stroke adjusted by dial
14 Hook Vertical-axis 2-fold hook (Latch type)
15 Feed mechanism Box feed Complete box feed
Top and bottom feed
actuation mechanism
17 Lubrication By manual (Centralized tank lubrication system)
18 Lubricating oil JUKI New Defrix Oil No. 2 (equivalent to ISO standard VG32)
19 Bed size 517 mm x 178 mm
20 Space under the arm 255 mm x 99 mm
V belt effective diameter : ø93.3 mm
Outer diameter : ø160 mm Outer diameter : ø175 mm
22 Motor 2P, 400W, 4P, 400W
6 #30 to #5 #8 to #1
9By dial
10 Air cylinder type (with touch-back switch)
16 Timing belt
21 Hand wheel size

– 5 –
9Presser foot lift
No. Item Specifications
1Model LU-1560N (Standard gauge type) LU-1560N-7 (Standard gauge type)
LU-1561N (LU-2260 gauge type) LU-1561N-7 (LU-2260 gauge type)
2Model name 2-needle, unison feed, lockstitch 2-needle, unison feed, lockstitch machine
machine (Automatic lubrication) with automatic thread trimmer
(Automatic lubrication)
3Application For heavy-weight materials
4Sewing speed Max. 2,500 rpm
5Needle SCHMETZ 135 X 17 Nm 125 to 180 Standard : Nm 160
Applicable thread size
for sewing
Applicable thread size
to be cut
8 Stitch length Max. 9 mm (forward/reverse feed)
Hand lifter : 9 mm
Knee lifter : 16mm Automatic presser foot lifter : 16mm
Stitch length adjusting
mechanism
Reverse stitch adjusting Air cylinder type
method (with touch-back switch)
12 Thread take-up Slide thread take-up
13 Needle bar stroke 36 mm
2.5 mm to 6.5 mm 1 mm to 6.5 mm
Alternate foot stroke adjusted by dial Alternate foot stroke adjusted by dial
15 Hook Vertical-axis 2-fold hook (Latch type)
16 Feed mechanism Box feed
Top and bottom feed
actuation mechanism
Thread trimming
method
19 Lubrication Automatic lubrication (partially by manual)
20 Lubricating oil JUKI New Defrix Oil No. 2 (equivalent to ISO standard VG32)
21 Bed size 517 mm x 178 mm
22 Space under the arm 255 mm x 99 mm
23 Hand wheel size V belt effective diameter : ø93.3 mm Outer diameter : ø160 mm
24 Motor 2P, 400W, 4P, 400W SC-510
6#30 to #5
7—#30 to #5
10 By dial
11 By lever
17 Timing belt
18 —Cam-driven scissors type
14 Alternate foot stroke

– 6 –
No. Item Specifications
1Model LU-1565N
2Model name 2-needle, unison feed, lockstitch machine
(With organized split needle bar)
3Application For heavy-weight materials
4Sewing speed Max. 2,000 rpm
5Needle SCHMETZ 135 X 17 Nm 125 to 180 Standard : Nm 160
Applicable thread size
for sewing
Applicable threas size
to be cut
8 Stitch length Max. 9 mm (forward/reverse feed)
9 Presser foot lift Hand lifter : 9 mm Knee lifter : 16 mm
Stitch length adjusting
mechanism
Reverse stitch adjusting
method
12 Thread take-up Slide thread take-up
13 Needle bar stroke 33.36 mm
14 Alternate foot stroke 2.5 mm to 6.5 mm Alternate foot stroke adjusted by long hole
15 Hook Vertical-axis 2-fold hook (Latch type)
16 Feed mechanism Box feed
Top and bottom feed
actuation mechanism
Thread trimming
method
19 Lubrication By manual
20 Lubricating oil JUKI New Defrix Oil No. 2 (equivalent to ISO standard VG32)
21 Bed size 517 mm x 178 mm
22 Space under the arm 255 mm x 99 mm
23 Hand wheel size V belt effective diameter : ø93.3 mm Outer diameter : ø160 mm
24 Motor 2P, 400W, 4P, 400W
6#30 to #5
10 By dial
7—
11 By lever
17 Timing belt
18 —

– 7 –
MEMO

– 8 –
2. STANDARD ADJUSTMENT
(1) Needle entry position
(2) Longitudinal position of the feed dog
Conditions
•Needle bar at lowest dead point
•Feed amount : 0 mm
Conditions
•Needle bar at lowest dead point
•Feed amount : 0 mm
Model Dimension A
LU-1561N-7 11.5±0.1mm
LU-1511N-7 11±0.1mm
LU-1509N
LU-1561N 10 ±0.1mm
LU-1509NH
LU-1510N-7 9±0.1mm
LU-1560N-7
LU-1560N
LU-1508N 8.5±0.1mm
LU-1510N
LU-1510NA-7
LU-1508NH 8±0.1mm
LU-1565N
60mm
Top surface of
throat plate
A
aa’
a = a’
Standard gauge type
LU-2200 gauge type
47mm
A
Standard Adjustment
Standard Adjustment
Top surface of
throat plate

– 9 –
1. Set the stitch dial to “0 “.
2. Turn the handwheel to bring the needle bar to the lowest dead
point of its stroke.
3. Loosen clamping screw in the feed rocker.
4. Move the feed base and adjust so that needle enters the
center of the needle hole in feed dog . Then securely tighten
clamping screw in the feed rocker. (a = a’)
Checking method
1. Set the stitch dial to the maximum.
2. Turn the handwheel and make sure that feed dog does not come
in contact with the throat plate at the position where the feed dog
travels fully to the front or to the rear.
oThe throat plate comes in contact
with the feed dog and contacting
noise occurs and the throat plate
or the feed dog may be damaged.
o Irregular stitches may result.
1. Set the stitch dial to “0”.
2. Turn the handwheel to bring the needle bar to the lowest dead point
of its stroke.
3. Loosen clamping screw in the needle bar rocking rear arm.
4. In the state that the presser foot is raised, adjust the clearance be-
tween presser bar and walking bar to dimension A at the
position where the distance from the top surface of the throat plate
to the presser foot is 60 mm (standard gauge type) or 47 mm (LU-
2200 gauge type), Then securely tighten clamping screw in the
needle bar rocking rear arm.
(Caution) Tighten the screw so that the needle bar rocking shaft
has no thrust play.
oStitch skipping or needle breakage
will result.
o Poorly tensed stitches will result.
Adjustment Procedures Results of Improper Adjustment
Adjustment Procedures Results of Improper Adjustment

– 10 –
(3) Lateral position of the feed dog
Conditions
•Needle bar at lowest dead point
•Feed amount : 0 mm
(4) Height of the feed dog
Conditions
•Feed amount : 0 mm
•Height of feed dog is maximum.
Model Dimension A
LU-1509N 0.4 to 0.5mm
LU-1509NH
LU-1510N-7
LU-1511N-7
LU-1560N-7
LU-1561N
LU-1561N-7
LU-1510NA-7 0.7 to 0.9mm
LU-1508N 0.8 to 0.9mm
LU-1508NH
LU-1510N
LU-1560N
LU-1565N
Adjust so that A = B and C = D are almost obtained.
aa’
AB
A
a = a’
AB
CD
In case of 1-needle In case of 2-needle
Standard Adjustment
Standard Adjustment

– 11 –
1. Set the stitch dial to “0”.
2. Turn the handwheel to bring the needle bar to the lowest dead point
of its stroke.
3. Loosen clamping screw in the feed rocker.
4. Move the feed base and adjust so that needle enters the
center of the needle hole in feed dog . Then securely tighten
clamping screw in the feed rocker. (a = a’)
In addition, adjust the lateral clearances of feed dog in terms of
the window of throat plate to almost equal values. (A = B and C = D)
oStitch skipping or thread breakage
will result.
o Poorly tensed stitches will result.
o Needle breakage will result.
When the height of the feed dog is
higher than the specified value :
oStitch pitch becomes larger than
the scale of the feed dial.
oBalloon stitches will result.
oReturn of sewing product will oc-
cur.
oFeed dog comes in contact with the
knife, and the knife and the feed
dog may be damaged.
When the height of the feed dog is
lower than the specified value :
oStitch pitch becomes smaller than
the scale of the feed dial.
o Feed force will be deteriorated.
1. Set the stitch dial to “0”.
2. Turn the handwheel to bring the height of the feed dog to the maxi-
mum.
(Bring the needle bar to the lowest dead point of its stroke.)
3. Loosen setscrew in the feed bar slide fork, move feed bar slide
fork up or down and adjust feed dog from top surface of the
throat plate (center section) to the dimensionA. Then securely tighten
setscrew in the feed bar slide fork.
Adjustment Procedures Results of Improper Adjustment
Adjustment Procedures Results of Improper Adjustment

– 12 –
(5) Height of the hook
(6) Adjusting the inner hook guide
Conditions : When the inner hook guide travels to its back end.
: Press the inner hook stopper to the groove in the throat plate.
A
To come in close contact
with each other
Hook stopper section
1
±
0.1mm
Model Dimension A
LU-1510N-7 0.1 to 0.2mm
LU-1511N-7
LU-1560N-7
LU-1561N-7
LU-1508N 0.1 to 0.3mm
LU-1509N
LU-1508NH
LU-1509NH
LU-1510N
LU1560N
LU-1561N
LU-1565N
LU-1510NA-7 0.2 to 0.4mm
Standard Adjustment
Standard Adjustment

– 13 –
1. Loosen two setscrews in the screw gear (small).
2. Draw out hook in the direction of the arrow. (At this time, bring
No. 1 screw of setscrews to the front of the operator.)
3. Replace thrust plate and adjust so that a clearance of 1±0.1mm
is provided between throat plate and the top surface of hook
stopper section of hook .
(For the kind of thrust plate , refer to “5. Selective parts and con-
sumable parts”.)
4. Assemble hook so that the notched section of the shaft of hook
comes to the front of the operator and tighten setscrews .
(The notched section should align with No. 1 screw of setscrews
.)
o In case of 2-needle, left and right are the same adjustment value.
oStitch skipping or thread breakage
will result.
o Needle breakage will result.
oIrregular stitches will result.
When the clearance is larger than the
specified value :
o Loose stitches or thread breakage
will result.
When the clearance is smaller than
the specified value :
o Inner hook or inner hook guide may
be damaged.
1. Turn the handwheel to bring inner hook guide to its back end
position.
2. Turn inner hook in the reverse direction of rotation of the hook (in
the direction of arrow mark A) and fit the inner hook stopper to the
inner hook stopping section in throat plate .
3. Loosen setscrew in the inner hook guide arm and adjust the
clearance between inner hook guide and the protruding section
of inner hook to dimension A.
4. After the adjustment, securely tighten setscrew in the inner hook
guide arm.
o In case of 2-needle, left and right are the same adjustment value.
Adjustment Procedures Results of Improper Adjustment
Adjustment Procedures Results of Improper Adjustment

– 14 –
Model Dimension B Dimension C Dimension D
LU-1510N-7 2.3±0.2mm 1.5±0.2mm 0.05 to 0.1mm
LU-1511N-7
LU-1510NA-7
LU-1560N-7
LU-1561N-7
LU-1508N 1.5 ±0.3mm 0.05 to 0.15mm
LU-1509N
LU-1510N
LU-1560N
LU-1561N
LU-1508NH 2.5±0.3mm
LU-1509NH
LU-1565N 18 mm 2.8±0.3mm
(7) Needle-to-hook timing
Conditions : Feed amount : 0 mm
: Needl bar rises from the lowest dead point of its stroke.
A
0.1 to 0.2mm
D
Model Dimension A
LU-1510N-7 58.7mm
LU-1510NA-7
LU-1511N-7 57.7mm
LU-1508N 56.7mm
LU-1510N
LU-1509N 55.7mm
LU-1561N-7 55.9mm
LU-1560N-7 56mm
LU-1561N 53.9mm
LU-1560N 54mm
LU-1508NH 52.3mm
LU-1509NH 51.3mm
Screw gear
(large)
+0.3
–0.1
BC
Standard Adjustment

– 15 –
oStitch skipping or thread breakage
will result.
o Loose stitches will result.
1) Standard of the lowest dead point of the needle bar
1. Set the stitch dial to “0”.
2. Turn the handwheel to bring needle bar to the lowest dead point
of its stroke.
3. Loosen the setscrew in the face plate to remove the face plate.
4. Loosen clamping screw in the needle bar holder. At this time,
loosen the screw to such an extent that needle bar moves up
and down by hand since needle bar drops if the screw is fully
loosened.
5. Adjust the distance from the lower end of needle bar frame to the
lower end of the needle bar to dimension A. Then tighten clamping
screw in the needle bar holder. (For LU-1510N-7, there is an
engraved marker line in needle bar .)
2) Needle-to-blade point of hook timing
1. Set the stitch dial to “0”.
2. Loosen two setscrews in the screw gear (large).
3. Turn the handwheel and when dimensions B and C are approxi-
mately obtained, loosen setscrew A and setscrew B in the
hook shaft driving saddle. Then move the hook driving shaft saddle
to the right or left to adjust the clearance between needle and
blade point of the hook to dimension D. Then securely tighten
setscrew A and setscrew B .
4. Turn the handwheel and move the screw gear (large) to the right or
left so that needle aligns with blade point of the hook when
needle bar is raised from the lowest dead point of its stroke to
dimension B. Then tighten two setscrews .
5. Turn the handwheel and loosen clamping screw in the needle
bar holder to adjust so that the distance from the top end of the
eyelet of needle to blade point of the hook becomes dimen-
sion C when needle bar is raised from the lowest dead point of its
stroke to dimension B. Then tighten again the clamping screw. (For
LU-1510N-7 and LU-1510NA-7 there is an engraved marker line in
needle bar .) However, in case of LU-1565N, loosen clamping
screws and and turn needle clamp to adjust. Then tighten
again the clamping screws. The range to turn needle clamp is as
wide as the clearance between the width of long hole of needle bar
and clamping screw .
6. Set the stitch dial to the maximum and check that needle does
not come in contact with blade point of the hook. (For the dimen-
sion, refer to the respective models in the list.)
3) Adjusting the needle guard of the hook
1. Bend needle guard and adjust so that the needle guard comes
in contact 0.1 to 0.2 mm with the needle.
(Caution) 1. Check that the hook shaft screw gear has backlash.
2. In case of 2-needle. left and right are the same ad-
justment value.
Adjustment Procedures Results of Improper Adjustment

– 16 –
(8) Lift of the presser foot
1) Hand lifter
Condition
•State that the hand lifter is raised
2) Knee lifter (Without thread trimmer only)
Top surface of
throat plate
9±0.3 mm
knee lifter lever A knee lifter lever B
Top surface of
throat plate
16±0.5 mm
Conditions : Lifting amount when stopper
screw comes in contact
with knee lifter lever A
Standard Adjustment
Standard Adjustment