HE-800B
11. TROUBLESHOOTING
151
11-3. Uneven seams (1) …… At the sewing start
Items with a “*” in the “Page” column should only be handled by a qualified technician.
Cause
Check
Remedy
Page
Upper thread trimmer Installation height
Adjust the upper thread trimmer installation height.
100
Upper thread trimmer
opening timing
Adjust to an appropriate opening timing.
101
Upper thread trimmer
operation
Apply grease to the inclined face of the opening cam.
101
Upper thread feeding
Thread take-up amount
Loosen the screw to decrease thread take-up amount
so that upper thread does not pull out of trimmer
assembly at the sewing start.
109
Lower thread (bobbin
slip)
Lower thread tension
Adjust the lower thread tension appropriately.
INSTRUCTION
MANUAL CD
Bobbin holder spring
Add tension to the bobbin holder spring.
–
Lower thread retainer
position
Adjust the lower thread retainer position.
*
Adjust lower thread retainer so that a 35 - 40 mm
thread leader is left after trimming.
104
Bobbin presser position
Adjust the bobbin presser position.
106
Bobbin insertion
Insert the bobbin correctly.
INSTRUCTION
MANUAL CD
4000Q
Screw
Increase
Decrease
4001Q
Add tension to the spring by the same
amount that the bobbin tab is projecting.
Make a gap
4002Q
35 – 40 mm
Summary of Contents for HE-800B
Page 7: ...v HE 800B Oil tank accessory 4732M 4731M 4730M ...
Page 75: ...6 ASSEMBLY HE 800B 66 D E 0688D 0690D ...
Page 126: ...9 ELECTRIC MECHANISM HE 800B 117 Power PCB Cutter PCB LCD panel PCB 0831D 0768D 0769D ...
Page 133: ...9 ELECTRIC MECHANISM HE 800B 124 0851D ...
Page 134: ...9 ELECTRIC MECHANISM HE 800B 125 0852D ...
Page 135: ...9 ELECTRIC MECHANISM HE 800B 126 0853D ...
Page 177: ...MEMO 168 HE 800B ...
Page 178: ...SERVICE MANUAL 2014 Brother Industries Ltd All Rights Reserved HE 800B I3061003D 2014 03 D 1 ...