Janome Continental M7 Professional User manual

1
SERVICE MANUAL
MODEL: Continental M7 Professional
First Edition: 06 August 2019

2
INDEX
Changing external parts
Face plate......................................................................................................................................................... 1
Top cover .......................................................................................................................................................... 1
Belt cover ......................................................................................................................................................... 2
Base ................................................................................................................................................................. 2
Power supply cover .......................................................................................................................................... 3
Thread cutter cover .......................................................................................................................................... 3
Front cover ....................................................................................................................................................... 4
Rear cover ........................................................................................................................................................ 5
Arm thread guide unit ....................................................................................................................................... 6
Replacing Electronic Components
Changing the printed circuit board A................................................................................................................ 7
Changing the printed circuit board F and slide volume.................................................................................... 8
Changing the front panel .................................................................................................................................. 9
Changing the LCD unit and LCD supporter plate........................................................................................... 10
Wiring diagram ................................................................................................................................................11
Mechanical Adjustment
Needle drop position adjustment.................................................................................................................... 12
Backlash between hook drive gear and lower shaft gear .............................................................................. 13
Hook timing adjustment...................................................................................................................................14
Needle bar height adjustment ........................................................................................................................ 15
Clearance between needle and tip of the rotary hook adjustment (1)............................................................ 16
Clearance between needle and tip of the rotary hook adjustment (2) ............................................................17
Height and direction of presser bar adjustment ............................................................................................. 18
Feed dog height adjustment........................................................................................................................... 19
To replace needle thread tension unit ............................................................................................................ 20
Tension release mechanism adjustment........................................................................................................ 21
Upper thread tension adjustment ................................................................................................................... 22
Bobbin winder stopper adjustment................................................................................................................. 23
Needle threader hook position ....................................................................................................................... 24
Thread cutter switch adjustment .................................................................................................................... 25
Thread drawing lever height adjustment ........................................................................................................ 26
Automatic upper feed withdrawal rod adjustment .......................................................................................... 27
Automatic upper feed adjustment (1).............................................................................................................. 28
Automatic upper feed adjustment (2) ............................................................................................................. 29
Upper feed dog (1).......................................................................................................................................... 30
Upper feed dog (2) ......................................................................................................................................... 31
To replace the thread take-up lever................................................................................................................ 32
To attach lower shaft ...................................................................................................................................... 33
Synchlo belt.................................................................................................................................................... 34
To replace the brushless DC motor and belt tension adjustment .................................................................. 35
Upper shaft shield plate position.................................................................................................................... 36
Buttonhole lever position adjustment ............................................................................................................. 37
Stretch stitch feed balance adjustment .......................................................................................................... 38
Presser foot lifter stopper position (1)............................................................................................................. 39
Presser foot lifter stopper position (2) ............................................................................................................ 40
Automatic presser foot lifter initializing sensor position ..................................................................................41
Preseer foot height on needle plate adjustment............................................................................................. 42
Presser bar lifter switch position .................................................................................................................... 43
To replace and adjust the needle plate sensor switch ................................................................................... 44
To replace the switching power supply unit.................................................................................................... 45
Drop down switch adjustment ........................................................................................................................ 46
Feed dog troubleshooting .............................................................................................................................. 47
Knee lifter adjustment .................................................................................................................................... 48
Optical bottom thread sensor adjustment ...................................................................................................... 49
PARTS LIST...............................................................................................................................50-75

1
Changing external parts (1)
To remove:
1. Remove the setscrew A and remove the face plate.
To attach:
1. Attach the face plate with the setscrew A.
Face plate
Top cover
To remove:
1. Remove the setscrews B (3 pcs.).
2. Remove the bobbin winder connector 1, bobbin
winder connector 2 and remove the top cover.
* Bobbin winder connector 1 and 2 are located rear
side of the touch panel (LCD screen).
To attach:
1. Insert the bobbin winder connector 1, bobbin winder
connector 2 and x the top cover with setscrews B (3
pcs.).
Setscrew A
Face plate
Top cover
Setscrew B
Setscrew B
Setscrew B
Bobbin winder connector 1
Bobbin winder connector 2

2
Base
To remove:
1. Remove the setscrews B (8 pcs.) and remove the
base.
To attach:
1. Attach the base with the setscrews B (8 pcs).
Setscrew B
Base
Changing external parts (2)
Belt cover
To remove:
1. Remove the top cover. (Refer to page 1)
Remove the caps and setscrews A (4 pcs.) and
remove belt cover.
To attach:
1. Attach the belt cover and tighten the setscrews A
(4 pcs.).
Belt cover
Setscrew A
Setscrew A
Setscrew A
Setscrew A
Hook
Hook
Block of approximately height 2 cm
Cap
Cap
Rubber foot

3
Changing external parts (3)
Thread cutter cover
To remove:
1. Remove the base. (Refer to page 2).
2. Loosen the setscrew B and remove the thread cutter
cover.
To attach:
1. Attach the thread cutter cover with the setscrew B.
Setscrew B
Thread cutter cover
Power supply cover
To remove:
1. Remove the setscrews A (3 pcs) and remove the
power supply cover.
To attach:
1. Attach the power supply cover with setscrews A
(3 pcs.).
Setscrew A
Setscrew A
Power supply cover
Hook

4
To remove:
1. Remove the face plate, top cover and belt cover.
(Refer to pages 1 and 2)
2. Loosen the setscrews A (5 pcs.).
3. Remove the setscrews B (2 pcs.).
4. Disconnect the printed circuit board U2 exible cable,
the printed circuit board L1 connectors (2 pcs.),
the printed circuit board F connector, the slide volume
connector and the rotary encoder connector.
Remove the front cover.
To attach:
1. Follow the steps of removal procedure in reverse.
Changing external parts (4)
Front cover
Printed circuit board U2 exible cable
Slide volume connector
Printed circuit board F connector
Rotary encoder connector
Setscrew A
Setscrew A
Setscrew A
Setscrew A
Setscrew A
Setscrew B
Printed circuit board L1 connector

5
Changing external parts (5)
To remove:
1. Remove the setscrews (3 pcs.) and remove the rear
cover.
To attach:
1. Attach the rear cover with the setscrews (3 pcs.).
Rear cover
Setscrew Setscrew
Setscrew

6
Changing external parts (6)
To remove:
1. Remove the face plate and top cover. (Refer to page 1)
2. Loosen the setscrews (2 pcs.), and remove the arm
thread guide unit.
To attach:
1. Follow the steps of removal procedure in reverse.
Setscrew
Setscrew
Arm thread guide unit
Arm thread guide unit

7
Changing the printed circuit board A
To remove:
1. Remove the face plate, top cover, belt cover and
front cover. (Refer to page 1 to 4)
2. Remove the setscrews A (2 pcs.) and remove the belt
cord guide.
3. Remove the setscrews B (4 pcs.) and disconnect all
the connectors from the printed circuit board A.
Remove the printed circuit board A.
To attach:
1. Follow the steps of removal procedure in reverse.
* Refer to page 11 for how to connect/ disconnect
the connectors to the printed circuit board A.
Setscrew BSetscrew B
Setscrew B
Setscrew A
Belt cord guide
Setscrew A
Setscrew B
Printed circuit board A

8
Changing the printed circuit board F and slide volume
Printed circuit board F
To remove:
1. Remove the front cover. (Refer to page 4)
2. Disconnect the connector for printed circuit board F.
3. Remove the setscrews A (3 pcs.) and reomve the
printed circuit board F.
To attach:
1. Follow the steps of removal procedure in reverse.
Printed circuit board F
Printed circuit board F
Slide volume
Slide volume
To remove:
1. Remove the front cover. (Refer to page 4)
2. Remove the snap rings CS-3 (2 pcs.) and remove the
slide volume.
To attach:
1. Follow the steps of removal procedure in reverse.
* Insert the projection of slide volume into the
convex of speed control slider and x it with the
snap rings (indicated by the arrow).
Setscrew A
Snap ring CS-3
Connector for printed
circuit board F

9
Changing the front panel
Setscrew B
Setscrew A
Setscrew A
Setscrew B Front panel 2
Front panel unit
Front panel unit
To remove:
1. Remove the front cover. (Refer to page 4)
2. Remove the setscrews A (2 pcs.).
Unhook the front panel 2 from the front panel unit and
remove the front panel 2.
3. Remove the setscrews B (4 pcs.) and remove the
front panel unit.
4. Remove the caps (2 pcs.), the nuts (2 pcs.), rotary
encoders (2 pcs.) and remove the front panel unit.
To attach:
1. Follow the steps of removal procedure in reverse.
Cap
Hook
Hook
HookHook
Nut
Cap
Rotary encoderRotary encoder
Front panel 2
Nut

10
Changing the LCD unit and LCD supporter plate
To remove:
1. Remove the front cover, front panel 2 and front panel
unit. (Refer to pages 4 and 8)
2. Remove the setscrews A (4 pcs.) and LCD unit.
3. Remove the setscrews B (3 pcs.) and LCD supporter
plate.
To attach:
1. Follow the steps of removal procedure in reverse.
Front panel unit
LCD supporter plate
Setscrew B LCD unit
Setscrew A
Setscrew A

11
Wiring diagram
Refer to this wiring diagram for locating the connectors on the printed circuit board A.
(Front side)
(Arm side)
Printed circuit board U2
(Flexible cable)
Printed circuit board L1 (Blue 2P)
Printed circuit board F (Black 18P)
Printed circuit board L2 (White 2P)
Thread cut detection sensor (Black 3P)
Presser foot lifting switch (Black 2P)
ErP switch (Green 2P)
Presser foot lifting motor (Black 8P)
Upper feed disengagement
motor (Black 7P)
Thread tension motor (White 7P)
Bight motor (White 7P)
Printed circuit board B (White 5P)
Blushless DC motor (White 14P)
Printed circuit board L3 (Red 2P)
Printed circuit board L1 (Black 2P)
Rotary encoder (White 6P)
Slide volume (Black 3P)
BH sensor (Black 3P)
Phase sensor (Black 4P)
Printed circuit board U1 (Red 4P)
Printed circuit board B (Black 4P)
Switching power supply
(control) (White 4P)
Switching power supply
(motor) (White 5P)
Printed circuit board U1 (Black 24P)
Printed circuit board U1 (Black 20P)

12
Needle drop position adjustment
1. Remove the face plate and arm thread guide unit.
(Refer to pages 1 and 6)
Turn the power switch ON while pressing the start/
stop button and the reverse stitch button to enter the
factory setting mode.
2. Press the “Bobbin” key.
When you press “Bobbin” key in the factory setting
mode, the maximum stitch width will be set at 9.0
automatically.
Check the needle drop position.
3. If this is not the case, adjust as follows;
Loosen the setscrew and turn the eccentric pin.
(The direction of eccentricity should be in the upper
part.)
4. Tighten the setscrew.
5. Attach the arm thread guide unit and face plate.
When you enter the factory setting mode, the needle should be positioned in the center of
the needle plate hole.
When the “Bobbin” key is pressed, the clearance between the side of the needle and needle
hole should be 0.2 mm or more.
Needle hole
0.2 mm or more
0.2 mm or more
A = B
Setscrew
Eccentric pin
Reverse button
Start/stop button
Eccentricity
Eccentricity is to be
adjusted in the upper
part.

13
Backlash between hook drive gear and lower shaft gear
The gears should turn smoothly and rotary play of the hook should be 0.8 mm or less when
the tip of hook is within the width of the feed dog as shown below.
1. Remove the base. (Refer to page 2)
2. Remove the needle and presser foot.
3. Push and turn the needle plate release dial in direction
A with the screwdriver.
Remove the needle plate and bobbin holder.
* LED light can be too bright when the machine lay
on its side.
4. Turn the handwheel toward you so that the tip of the
rotary hook is within the width of feed dog. Turn the
rotary hook and check the clearance.
5. If the backlash is too much or too little, loosen the
setscrews of lower shaft bushings (both front and
rear) and adjust the backlash following the adjustment
procedure in step 6.
* Turn the lower shaft bushings (front and rear) in
the same direction simultaneously and evenly.
6. If the backlash is too much, turn the lower shaft
bushings (front and rear) in direction A.
If the backlash is too little, turn the lower shaft
bushings (front and rear) in direction B.
7. Tighten the setscrews.
* After adjusting the backlash, check the needle bar
height and hook timing. Adjust if necessary.
8. Attach the bobbin holder, needle plate, presser foot
and needle.
9. Attach the base.
Lower shaft bushing (front)
Setscrew
Width of feed dog
Tip of hook
Needle plate
release dial
(A)
(B)
Setscrew
Lower shaft bushing of the front side
Lower shaft bushing on the rear side
Setscrew
Lower shaft bushing (rear)
AB

14
Needle plate
release dial
1. Remove the base. (Refer to page 2)
2. Attach the #14 needle.
3. Turn the power switch on and select the straight
stitch #4 ( ). Set the zigzag width at “0.0” (left
needle position) and turn the power switch off.
4. Remove the presser foot.
5. Push and turn the needle plate release dial in direction
A with the screwdriver.
Remove the needle plate and bobbin holder.
* LED light can be too bright when the machine lay
on its side.
6. Lower the needle bar to the lowest position by turning
the hand wheel toward you.
7. Loosen the setscrews (2 pcs.) of the lower shaft gear.
8. Move the needle bar 3.85 mm up from the lowest
position by turning the hand wheel toward you.
9. Turn the lower shaft gear until the tip of the hook
meets the right side of the needle, and then tighten
the setscrews (2 pcs.).
* After adjusting the hook timing, check the needle
bar height.
10. Attach the bobbin holder, needle plate and presser
foot.
11. Attach the base. (Refer to page 2)
Hook timing adjustment
The amount of ascending travel of the needle bar from its lowest position to the position
where the tip of the rotary hook exactly meets the right side of the needle in the left needle
position (“0.0”) should be 3.70 to 4.00 mm.
Setscrew
Setscrew
Lower shaft gear
3.70 to 4.00 mm
Lowest needle
position
Needle #14
The tip of the rotary hook
exactly meets the right side of
the needle.
Bobbin holder
Rotary hook
AB

15
Needle bar height adjustment
1. Attach the #14 needle.
2. Turn the power switch on and select the straight
stitch #4 ( ). Set the zigzag width at “0.0” (left
needle position).
* Do not turn the power switch off.
3. Remove the presser foot.
4. Remove the cap.
Push and turn the needle plate release dial in direction
A with the screwdriver.
Remove the needle plate and bobbin holder.
* LED light can be too bright when the machine lay
on its side.
5. Remove the face plate and arm thread guide (unit).
(Refer to page 6)
6. Turn the handwheel toward you until the tip of the hook
meets right side of the needle.
7. Loosen the setscrew with an allen wrench. Move the
needle bar and adjust needle bar height to 1.8 mm.
8. Tighten the setscrew with the needle setting groove to
the front.
9. Attach the arm thread guide (unit) and face plate.
10.Attach the bobbin holder, needle plate and presser
foot.
Needle setting groove
The hook meets right
side of the needle
Hook race
1.6 to 2.0 mm
Upper edge of
needle hole
Before proceeding with this adjustment, check the hook timing. (Refer to page 14)
The distance between the upper edge of the needle eye and the tip of the hook should be in
the range of 1.6 to 2.0mm when the tip of the hook meets right side of the needle in the left
needle position (“0.0”) as the needle ascends from its lowest position.
Setscrew
Needle #14
Bobbin holder
Rotary hook
AB
Needle plate
release dial
Cap

16
Clearance between needle and tip of the rotary hook adjustment (1)
The clearance between the needle and the tip of the rotary hook should be between -0.10 to
+0.05 mm.
Test pin
Tip of hook
-0.10 to +0.05mm
0.2 mm
0.2 mm
Clearance adjustment 1
1. Remove the face plate and top cover. (Refer to
page 1)
2. Remove the presser foot.
3. Remove the cap.
Push and turn the needle plate release dial in direction
A with the screwdriver.
Remove the needle plate and bobbin holder.
* LED light can be too bright when the machine lay
on its side.
4. Attach the test pin.
5. Turn the power switch ON while pressing the start/
stop button and the reverse stitch button to enter the
factory setting mode.
Press the “Bobbin” key.
When you press “Bobbin” key in the factory setting
mode, the maximum stitch width will be set at 9.0
automatically.
6. Loosen the setscrew and adjust the clearance
between the needle and the tip of the rotary hook as
-0.10 to +0.05 mm, by moving the needle bar
supporter in the directions of arrows.
7. Tighten the setscrew.
8. Attach the needle plate.
Be sure that the clearance between the needle and
the upper edge of the needle plate hole and the clea-
rance between the needle and the lower edge of the
needle hole are nmore than 0.2 mm.
* If the clearance are less than 0.2 mm, adjust the
Clearance between needle and tip of the rotary
hook adjustment (2) on the next page.
Setscrew
Needle bar supporter
Needle hole
Needle
Bobbin holder
Rotary hook
Reverse button
Start/stop button
AB
Needle plate
release dial
Cap

17
Clearance adjustment 2
1. Remove the base. (Refer to page 2)
2. Loosen the setscrews A, B and C, and tighten
setscrew C lightly.
3. Adjust the clearance by moving the hook setting plate.
Turn the handwheel and make sure that the clearance
between the needle and the tip of the rotary hook is
-0.10 to +0.05 mm.
4. Tighten the setscrews A, B and C rmly.
* Check the backlash between hook drive gear and
lower shaft gear, hook timing and needle bar height.
Adjust, if necessary after the adjustment.
5. Attach the base, bobbin holder, needle plate, presser
foot and needle.
Setscrew C
Setscrew B
Setscrew A
Hook setting plate
Clearance between needle and tip of the rotary hook adjustment (2)
The clearance between the needle and the tip of the rotary hook should be between -0.10 to
+0.05 mm.

18
Height and direction of presser bar adjustment
The clearance between the presser foot and the surface of the needle plate should be 6.0
mm when the presser foot is raised with the presser foot lifter.
The presser foot should be parallel to the slot of the feed dog teeth when attached.
1. Attach the zigzag foot A.
2. Remove the face plate. (Refer to page 1)
3 . Turn the power switch ON while pressing the start/
stop button and the reverse stitch button to enter the
factory setting mode.
Press the “Feed Dog” key to select the feed dog
adjusting mode.
4. Press the drop feed key to drop the feed dog.
Press the presser foot lifter button to lower the
presser foot.
5. Raise the presser foot lifter lever.
6. Loosen the setscrew on the presser bar supporter to
adjust the presser foot direction so that the slot for the
feed dog teeth and the zigzag foot should be parallel.
7. Place a 6 mm block between the presser foot and the
needle plate.
Tighten the setscrew holding the presser foot against
the block.
Setscrew
(2 mm width
across ats)
Presser
foot
Presser bar
supporter
Drop feed key
Needle plate
Needle plate
Approximately
6.0 mm
Block
Presser foot lifter lever
Setscrew
Slot
Should be
parallel
Reverse button
Start/stop button
Presser foot lifter button
Approximately
6.0 mm