Trouble Shooting Guide - JUKI MO-2800 Instruction Manual

Trouble shooting guide

Problem
The machine • Looper or cloth plate cover is open.
does 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.
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 tension
tion dials.
• Thread has got caught.
• Machine is incorrectly threaded.
Seams flute or • Fabric was pulled while sewing.
wave, especial- • Presser foot pressure is too tight.
ly when sewing • Differential feed is set incorrectly.
knits
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
Motor failure • Noise is heard.
• Motor does not turn at all.
• Sparks are abnormally large.
Needle eyelet • The "
cannot be thread- is not aligned with the "
ed handwheel.
Upper and lower • When the handwheel is not fixed.
loopers cannot be
threaded • When the thread is not inserted into the bottom
of the threading hole.
• When the thread is not slacked before the
threading hole.
• When the thread is caught somewhere in the
thread path.
• When the pipe is clogged with lint.
35
Cause
" marking on the side of the front cover
" marking on the
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.
• Reduce thread tension.
• Check the threading.
• Insert needles fully into needle clamp with
flat side to the back.
• Use needle system 130/705H or JLx2.
• 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 JLx2.
• Increase presser foot pressure.
• Check if thread is lying between tension
discs.
• Raise the presser foot and pull the thread.
• Check threading path of each 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.
• Replace the carbon brush with a new one.
(Note) Contact your distributor to ask for the
replacement of the carbon brush.
• Turn the handwheel to align the "
marking on it with the "
side of the front cover.
• Raise the threading changeover lever and
turn the handwheel to fix it.
• Insert the thread into the threading hole
by 1 to 2 cm.
• Slack the thread before the threading
hole.
• Remove the thread from the location
where it has been caught.
• Thread the loopers by means of the loop-
er threader supplied in the accessory bag
to remove the lint in the pipe.
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