Janome Magnolia 7312 User manual

SERVICE MANUAL
MODEL 7312

TABLE OF CONTENTS
0. Dismantling the rear cover
1. Upper shaft end play
2. Cam stack gear mesh
3. Needle bar height
4. Shuttle timing
5. Needle position
6. Zeroing the needle
7. Feed dog height
8. Feed lifting cam
9. Stretch stitch selector cam
10. V belt adjusting
11. Bobbin winder
12. Take-up spring replacement and setting
13. Bobbin case tension
14. Stretch stitch sewing
15. BH balance
16. Electrical connections
PAGE
1
2
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4
5
6
7
8
9
10
11
12-13
14
15
16
16
17

0. DISMANTLING THE REAR COVER
1. Unscrew the screws: a. b. c. d. e. f.
2. Open face cover and shuttle cover and pull out the spool
pins.
3. Remove the rear cover in direction of arrow.
a
b
e
f
c
d
spool pins
face cover
shuttle cover
1

1. UPPER SHAFT END PLAY
Check : 1. Hold clamp of stop motion by hand , check play
that push in and pull out on upper shaft.
According with above method, recheck upper
shaft play at any point during the revolution.
Adjustment : 1. Remove rear cover .
2. Loosen set screw (C) (Hexagen M5x5) in collor.
3. Plate screwdriver blade (E) between stop
clamp motion and casting body .
4. Hold collor (B) to left touch with slide front
spherical bearing of upper shaft (A) then
tighten set screw (C).
5. Take out screwdriver (E).
6. Recheck for end play.
(ALL MODELS)
2
ABCD
E
Front spherical bearing
Stop clamp motion

2. CAM STACK GEAR MESH
Check : 1. Remove rear cover.
2. Place machine in straight stitch.
3. Check at three different points in a full
revolution, zero or very slight play is
acceptable.
Adjustment : 1. Loosen set screw (E).
2. Hold gear (F) slightly forward, but can not
turn.
3. If machine marked bind, must be remove
backward.
4. Tighten set screw (E).
5. Recheck pendulum timing.
(ALL MODELS)
3
F
E

3. NEEDLE BAR HEIGHT
Check : 1. Take out bobbin case and shuttle race cap.
2. Select zigzag and max , width stitch.
3. Rotate hand wheel until needle is full down in
right position.
4. Then , slowly raise needle bar to (a) position ,
the distance shall be 1 mm.
Adjustment : 1. Open face cover.
2. Loosen needle bar clamp screw (A).
3. Slightly move needle bar (B) up or down until
location is 1 mm.
4. Tighten clamp screw (Torque 15kg-cm).
Attention : 1. After completing adjustment, make sure that
needle is parallel to shuttle.
(ALL MODELS)
AB
L
R
1 mm
shuttle hook
4
a

4. SHUTTLE TIMING
Check : 1. Take out bobbin case and shuttle race cap.
2. Select zigzag and max, width stitch.
3. Rotate hand wheel until needle is full down in
the left needle position.
4. The point of shuttle shall be 3.2 mm to the left
of needle.
Adjustment : 1. Remove rear cover.
2. Loosen 2 screw (A) on driver gear.
3. Slightly turn driver gear (B) clockwise to
decrease clearance and counter clockwise
to increase clearance.
4. Tighten both screw (A) and recheck.
(ALL MODELS)
C
A
B
3.2 mm
Shuttle hook
5
Lower shaft
a

5. NEEDLE POSITION
Check :
1. Set machine for zigzag max, width.
2. Turn machine by hand and
observe needle as it enters the
needle plate , left and right entry
should be equal distance from the
edge of the needle plate hole (A).
Adjustment :
1. Open face cover.
2. Loosen set screw (D) and (B).
3. Turn eccentric (C) as (A) shown.
(correct needle location).
4. Tighten set screw (B) and (D).
5. Check distance must be 0.4 mm
between needle bar and stopper
plate at the left or right position.
(ALL MODELS)
A
5 mm
D
B
C
0.4 mm
6

6. ZEROING THE NEEDLE
Check : 1. Select straight stitch position.
2. Sewing a line straight stitch.
3. Shall be no or minimul movement below
0.3 mm.
Adjustment : 1. Remove rear cover.
2. Select straight stitch position.
3. Loosen screw (or nut ) (A).
4. Remove connecting plate (B) so that no or
minimul movement of needle bar.
5. Tighten screw (or nut ) (A).
(ALL MODELS)
A
B
BA
C
Model
Model
7

7. FEED DOG HEIGHT
Check : 1. Bring feed dog to it's highest point.
2. The top or the feed dog should be 0.8-1.0 mm
above the surface of the needle plate.
Adjustment : 1. Remove rear cover.
2. Bring feed dog to it's highest point.
3. Loosen nut (A).
4. Turn set screw (B) as required.
5. Tighten nut (A).
(ALL MODELS)
0.8~1.0 mm
Feed dog
Needle plate
8
A
B