Needle And Feed Timing Adjustment; Thread Cutter Timing Adjustment - Brother b831 Service Manual

(T) NEEDLE AND FEED TIMING ADJUSTMENT (standard)
Reference line
o
—
TIM
9
1. Remove the needle.
2. Tilt the machine head back and remove timing belt O
3. Turn the machine pulley until position A is in line with the red dot.
4. With the upper shaft held still, align the arrow on the timing belt wheel lowerO with the reference line on the arm bed.
and install timing belt O-
5. Pull the machine head back to its original position, and install the needle.
Thread cutter timing adjustment
T mark
Less than 2 mm
Red dot
ffi Thread cutter timing confirmation
1, Remove the needle and tilt the machine.
2- Press the knife mam lever shaft O and turn the pulley in the normal direction until it is hard to turn.
3. The timing mark T on the pulley should be aligned with the red dot on the machine head. Allowable deviation is 2 mm
from the center of the dot.
©Upper and lower shaft timing adjustment
1, Remove the timing belt 0.
2, Turn the pulley and align the timing mark T with the red dot
3, Press the knife mam levershaft O and turn the lower belt wheel pulley O m the direction of the arrow until it is hard to
turn.
4, Hold the mam pulley and the lower belt wheel pulley 0 so they will not move, and then mount the timing bell 0.
5, Recheck the mam pulley timing mark T alignment.
*• Refer to lower belt pulley adjustment on page 27 if the lower bell pulley is not properly positioned,
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