JUKI MO-735N - Trouble Shooting Guide

Trouble shooting guide
Problem Cause Solution Page
The machine does
not sew:
• Looper or cloth plate cover is open.
• The main switch is not on.
• The machine is not plugged in.
• Close the looper or the cloth plate cover.
• Switch machine on. (Main switch to “I”)
• Insert plug into main socket.
11
9
7
Fabric does not
feed evenly
• Differential feed is wrongly adjusted.
• Presser foot pressure is too low.
• Lower or upper knife is blunt or wrongly
positioned.
• Check the differential feed setting.
• Adjust the presser foot pressure.
• Replace the lower or upper knife.
15
17
47
Thread breaks • Thread tension is too tight for the thread
being used.
• The machine is not threaded correctly.
• Needles are incorrectly inserted.
• Wrong needles.
• Reduce thread tension.
• Check the threading.
• Insert needles fully into needle clamp
with flat side to the back.
• Use needle system 130/705H or JL×2.
30,42
22 to 27,
34 to 40
12
12
Needles break • Needles are bent or blunt, points are
damaged.
• Needles are not inserted correctly.
• Fabric was pulled while sewing.
• Replace needles.
• Insert needles fully into needle clamp
with flat side to the back.
• Guide fabric gently with both hands.
13
12
--
Skipped stitches • Needles are bent or blunt.
• Wrong needles used.
• Presser foot pressure is too low.
• Replace the needles.
• Use needle system 130/705H or JL×2.
• Increase presser foot pressure.
13
13
17
Poor stitch forma-
tion
• Threads are not correctly between the
tension dials.
• Thread has got caught.
• Machine is incorrectly threaded.
• Check if thread is lying between tension
discs.
• Raise the presser foot and pull the
thread.
• Raise the presser foot and pull the
thread.
• Check threading path of each thread.
19
19
19
22 to 27,
34 to 40
Seams flute or
wave, especially
when sewing knits
• Fabric was pulled while sewing.
• Presser foot pressure is too tight.
• Differential feed is set incorrectly.
• Guide fabric gently.
• Reduce presser foot pressure.
• Adjust differential feed to N - 2.
--
17
15
Seams pucker • Needle thread tension is too tight.
• Differential feed is set incorrectly.
• Reduce the needle thread tension.
• Adjust differential feed to 0.7 - N.
30
15
Fabric edges curl • Too much fabric is in the stitch.
• Thread tension is too tight.
• Stitch selection lever is on roll hem.
• Reduce cutting width.
• Reduce thread tension.
• Set selection lever to overlock.
14
30
17
Thread loops are
too loose
• Too little fabric in the stitch. • Increase the cutting width. 14
48