Brother XR9000 Service Manual page 149

Repair Manual
Problem Primary factors and causes
10 Threading not Thread pushed out at the hook
possible end
• Vertical slippage in needle
Hook extends right of the needle
hole
• Wide gap between right side
• Needle curvature
• Needle slant (hole slant with
• Threader hook assy.
When the threader Threader shaft tangling
lever returns, it
stops part way
Bad thread guide shape
through.
Needle thread shaft and top gap
too small
Needle thread Bad needle stop position
lever operation
• NP sensor damage
catches part way
through.
• Grease or dirt adhering to
• Rotation shutter damage
• Bad needle thread block
11 Either upper thread Upper thread tension is tight/
tension or lower loose
thread tension
Lower thread tension is too tight/
loose
Upper thread or lower thread
unsuitable
6 - 6
thread block
of needle and hook guide
slanted attachment of
needle block)
slippage
NP sensor
rotational position
Repair method
Adjust needle thread (4-12)
Replace threader hook assy.
(2-31) (3-48)
Replace needle
Replace needle bar
(2-33) (3-46)
Replace threader hook assy.
(2-31) (3-48)
Replace needle holder assy.
(2-34) (3-44)
Replace threader hook assy.
(2-31) (3-48)
Replace needle holder assy.
(2-34) (3-44)
Replace main PCB assy.
(2-13) (3-13)
Remove grease and dirt
Replace upper shaft assy.
(2-17) (3-8)
Adjust needle thread block
(4-12)
Adjust upper thread tention
(4-5)
Adjust lower thread tension
(4-21)
Replace upper thread or lower
thread
Items for Inspection method
Inspection and standards
Threading Check that when
function threading is carried out
with Schappe Spun
Sewing Thread #60 /
#11 needle and
Schappe Spun Sewing
Thread #30 / #16
needle, that the
threading lever moves
smoothly and that
threading through the
needle hole is possible.
Upper thread Check that the thread
tension tension is good during
actual sewing.
Lower thread
tension