Trouble Shooting Guide - JUKI MO-735N Instruction Manual

Trouble shooting guide

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