ELNA eXperience 520 User manual

SERVICE MANUAL
MODEL: eXperience 520

TABLE OF CONTENTS
WHAT TO DO WHEN........................................................................................................ 1-3
SERVICE ACCESS (1) FACE COVER............................................................................... 4
SERVICE ACCESS (2) BED COVER ................................................................................. 5
SERVICE ACCESS (3)(4) FRONT COVER .................................................................... 6-7
SERVICE ACCESS (5) REAR COVER............................................................................... 8
MECHANICAL ADJUSTMENT
PRESSER BAR HEIGHT AND ALIGNMENT .............................................................................. 9
NEEDLE DROP POSITION ....................................................................................................... 10
NEEDLE TO SHUTTLE TIMING................................................................................................ 11
NEEDLE BAR HEIGHT.............................................................................................................. 12
NEEDLE CLEARANCE TO SHUTTLE ...................................................................................... 13
BACKLASH (BETWEEN LOWER SHAFT GEAR AND SHUTTLE HOOK GEAR).................... 14
FEED DOG HEIGHT.................................................................................................................. 15
ZIGZAG SYNCHRONIZATION.................................................................................................. 16
NEEDLE THREAD TENSION.................................................................................................... 17
STRETCH STITCH FEED BALANCE........................................................................................ 18
REPLACEMENT AND ADJUSTMENT OF THE NEEDLE THREADER PLATE ....................... 19
CONNECTOR DIAGRAM .......................................................................................................... 20
SELF DIAGNOSTIC TESTS ...................................................................................................... 21
SELF DIAGNOSTIC SHEET................................................................................................. 22-25
REPLACING PRINTED CIRCUIT BOARD A............................................................................. 26
REPLACING SLIDE VOLUME AND PRINTED CIRCUIT BOARD F......................................... 27
REPLACING DC MOTOR AND ADJUSTING MOTOR BELT TENSION .................................. 28
REPLACING THE FUSES ......................................................................................................... 29
REPLACING MACHINE SOCKET (UNIT) ................................................................................. 30
REPLACING THE TRANSFORMER ......................................................................................... 31
REPLACING THE ZIGZAG WIDTH MOTOR ............................................................................ 32
REPLACING THE FEED STITCH MOTOR ............................................................................... 33
ADJUSTING BUTTONHOLE LEVER POSITION ...................................................................... 34
ADJUSTING THE BOBBIN WINDER SWITCH ......................................................................... 35
OILING....................................................................................................................................... 36

1
MODEL 520
CONDITION CAUSE HOW TO FIX REFERENCE
1. Skipping
stitches 1. Needle is not inserted properly.
2. Needle is bent or worn.
3. Incorrectly threaded.
4. Needle or thread are
inappropriate for fabric being
sewn.
5. Sewing on stretch fabric.
6. Presser foot pressure is too
weak.
7. Inappropriate needle bar
height.
8. Inappropriate needle to shuttle
timing.
9. Inappropriate needle to shuttle
clearance.
Insert the needle properly.
Change the needle.
Rethread.
Use the recommended sewing needle
and thread.
Use a #11 blue tip needle.
Adjust the presser bar level to make the
pressure stronger.
See mechanical adjustment “Needle
bar height”.
See mechanical adjustment “Needle
to shuttle timing”.
See mechanical adjustment
“Clearance between needle and hook”.
P. 12
P. 11
P. 13
2. Fabric not
moving 1. Presser foot pressure is too
weak.
2. Incorrect f.d. Height.
3. Feed dog Is in down position.
4. Thread on bottom side of fabric
is jammed up.
5. Feed dog teeth are worn.
Adjust the presser bar level to make the
pressure stronger.
See mechanical adjustment “feed
dog height”.
Raise the feed dog Level.
Make sure to bring both needle and
bobbin thread under the foot when
starting sewing.
Change the feed dog.
P. 15
WHATTO DOWHEN

2
MODEL 520
P. 10
P. 13
P. 16
CONDITION CAUSE HOW TO FIX REFERENCE
3. Breaking
upper
thread
1. Initial sewing speed is too fast.
2.Thread path is incorrect.
3. Needle is bent or dull.
4. Upper thread tension is too
strong.
5. Needle size is inappropriate for
fabric.
6. Needle eye is worn.
7. Needle hole in needle plate is
worn or burred.
Start with medium speed.
Use the proper thread path.
Replace with a new needle.
Adjust needle thread tension correctly.
Use appropriate needle for fabric
and thread in use.
Change the needle.
Repair the hole or replace the needle
plate.
P. 17
4. Breaking
bobbin
thread
1. Incorrectly threaded bobbin.
2.Too much thread is around on
the bobbin.
3. Lint is stuck inside the bobbin
holder.
4.Thread quality is too low.
5.Thread is jamming around the
bobbin.
Thread bobbin correctly.
Adjust the position of stopper.
Clean the shuttle.
Change to a high quality sewing thread.
Clear out the jamming thread.
5. Needle breaks 1. Needle is hitting the needle plate.
2. Needle is bent or worn.
3. Needle is hitting the shuttle.
4.The fabric moves while the
needle is piercing it, or the
needle zigzags while in fabric.
5. Fabric is being pulled too
strongly while sewing.
See mechanical adjustment “needle
drop position”.
Change the needle.
See mechanical adjustment
“Clearance between needle and hook”.
See mechanical adjustment “Zigzag
synchronization”.
Guide the fabric gently while sewing.

3
MODEL 520
CONDITION CAUSE HOW TO FIX REFERENCE
6. Noisy
operation 1. Backlash between shuttle hook gear and lower shaft gear is too
great.
2. Lower shaft gear is loose.
3. Inappropriate belt tension.
4. Not enough oil.
See mechanical adjustment
“Backlash (lower shaft gear)”.
Eliminate the looseness.
See part removal and replacement
“driving motor (DC motor)”.
Oil all moving parts.
P. 14
P. 28
P. 36
7. Deformation
pattern 1. Inappropriate feed balance.
2. Inappropriate zigzag
synchronization.
3. Upper thread tension is too
strong.
See mechanical adjustment
“Stretch stitch feed balance”.
See mechanical adjustment
“Zigzag synchronization”.
See mechanical adjustment
“Needle thread tension”.
p. 18
P. 16
P. 17

4
MODEL 520
Cap
SERVICE ACCESS (1)
FACE COVER
TO REMOVE:
1. Remove the cap.
2. Remove the setscrew (A) and remove the face cover.
TO INSTALL:
3. Insert the three ribs and the hook on the face cover into the rear cover.
Tighten the setscrew (A) and attach the cap.
Ribs
Hook
Setscrew (A)
Face cover

5
MODEL 520
SERVICE ACCESS (2)
BED COVER
TO REMOVE:
1. Set the drop lever to the left and remove the three setscrews (A), remove the bed cover.
TO INSTALL:
2. Set the drop lever to the left and install the bed cover.
Secure it in place with the three setscrews (A).
Setscrew (A)
Setscrew (A)Drop lever
Bed cover
Setscrew (A)

6
MODEL 520
SERVICE ACCESS (3)
FRONT COVER
TO REMOVE:
1. Remove the face cover and bed cover (see pages 4 and 5).
2. Loosen the setscrews (A) and then remove the setscrew (B), (C), (D), (E) and (F).
3. Remove the front cover (see page 20) and disconnect each switch connector.
NOTES: TO DISCONNECT THE CONNECTORS:
Grasp the connector directly with your fingers and pull. Do not pull on the lead wire, as this may
damage the contact sleeve inside the connector.
TO INSTALL:
4. To install the front cover, follow the above procedure in reverse.
NOTES: TO CONNECT THE CONNECTORS:
1. Insert each connector into the connector post (on the printed circuit board) which has the
same color as that of the connector.
2. Insert the connector at the right angle. Then push it straight down until it locks in place.
Setscrew (B)
Setscrew (A)
Setscrew (C) Setscrew (D)
Setscrew (E)
Front cover Setscrew (F)

7
MODEL 520
SERVICE ACCESS (4)
HOW TO REMOVE THE FRONT COVER
1. Remove the hooks on the front cover and the rear cover (indicated by the white arrows) and
the hook on the base.
2. Remove the feed balancing dial.
3. Remove the machine socket, and then remove the front cover.
* Remove the setscrews (G) and (H) from the rear cover to remove the machine socket easily,
Setscrew (G) Setscrew (H)
Feed balancing
dial
Machine socket

8
MODEL 520
SERVICE ACCESS (5)
REAR COVER
TO REMOVE:
1. Remove the front cover (see pages 6 and 7).
2. Loosen the setscrews (A), (B), (C), (D) and (E).
* To remove the cover, detach the presser foot lifter section first, with the presser foot lifter in
the down position.
TO INSTALL:
3. Follow the above procedure in reverse.
Setscrew (A)
Setscrew (B)
Setscrew (C)
Presser foot lifter
Rea cover
Setscrew (D) Setscrew (E)