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PROBLEM
POSSIBLE CAUSE
CORRECTIVE ACTION
Skipping
Bad needle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check needle
Dirty shuttle area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Clean shuttle area
*Needle height or clearance out of adjustment . . . . . . . . . . . . . .Check Adjustment
Damage to shuttle hook or race cover spring . . . . . . . . . . . . . . .Check shuttle hook & race cover
spring — repair/replace
Breaking Needles
Needle not installed properly . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check needle
Operator forcing carpet or machine . . . . . . . . . . . . . . . . . . . . . . .Let machine do the work
Race cover spring clearance improper . . . . . . . . . . . . . . . . . . . .See instruction manual
Carpet type (i.e. Berbers) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Test on another type of carpet, use
softener on Berber
Upper Thread
Breaking
Needle clearance out of adjustment . . . . . . . . . . . . . . . . . . . . . . .Check adjustment
Bad needle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check needle
Upper tension set too high . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check tension
Carpet type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Test on another type carpet
Dirty Shuttle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Clean shuttle area
Burrs on shuttle area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Inspect shuttle parts and deburr
Burrs on bottom of needle plate . . . . . . . . . . . . . . . . . . . . . . . . . .Inspect and deburr
Bad upper thread . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Attempt to break between hands
Threading wrong . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check thread path
*Needle height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .See instruction manual
Upper Thread Loops
on Carpet Bottom
Upper thread not inserted properly in tension control . . . . . . . . .Check that out feed of tension control
has drag on thread
Too little upper tension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check tension setting
Dirty shuttle area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Clean shuttle
*Needle height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .See instruction manual
Upper Thread Tangles
**Shuttle drive spring deformed or broken . . . . . . . . . . . . . . . . . .Replace drive spring
in Shuttle and/or in
Binding on carpet with plastic backing (i.e. Unibond) . . . . . . . . . .Use lubricant
Cut on Carpet Bottom
Burrs on shuttle hook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Deburr hook
Binding carpet with backing where glue is not dry . . . . . . . . . . . .Allow to dry or use lubricant
Won’t Pick Up
*Needle height or clearance out of adjustment . . . . . . . . . . . . . .See instruction manual
Bobbin Thread
Bobbin tension incorrect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check tension
Damaged bobbin tension spring . . . . . . . . . . . . . . . . . . . . . . . . .Replace spring
Needle in wrong . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check needle
Too short of thread lead from bobbin case . . . . . . . . . . . . . . . . .Leave 2" of lead
Bobbin Thread Breaks
Bad bobbin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check thread strength
Burr on shuttle hook or race cover or bad bobbin case spring . . .Check each item
Stitch Misses Top or
Change in type of binding tape . . . . . . . . . . . . . . . . . . . . . . . . . .Check
Bottom of Binding
Cannot use cotton binding in polyester folder . . . . . . . . . . . . . . .Check
Carpet too thick . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Bevel carpet
Need to adjust folder position . . . . . . . . . . . . . . . . . . . . . . . . . . . .See instruction manual
Bobbin Thread Loose
Damaged or loose bobbin tension spring . . . . . . . . . . . . . . . . . . .Check spring
on Bottom of Binding
Dirt between bobbin tension spring & bobbin case . . . . . . . . . . .Remove spring & clean surfaces
Bobbin Case Pops Out
Bobbin case not latched . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check
Latch spring broken . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check latch & spring
Too wide needle clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Check adjustment
*The most common cause of thread breaking, skips, loops, and not picking up bobbin thread is the needle bar being out of adjustment. The adjustment is shown
both on the first adjustment instruction sheet and in the video.
**New and most updated and refurbished machines now have a springless driver.
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TROUBLESHOOTING