HE-800B
11. TROUBLESHOOTING
165
11-24. Work clamp is not raised (2) ……Error occurs.
Items with a “*” in the “Page” column should only be handled by a qualified technician.
Cause
Check
Remedy
Page
Upper thread trimmer Interference between
upper thread trimmer and
work clamp
Adjust the installation height of the upper thread
trimmer (remove the upper thread trimmer and check).
*
Be particularly careful when sewing joints.
100
Upper thread trimmer
operation
Apply grease to the inclined face of the opening cam.
101
Lower thread trimmer Interference between fixed
knife set, lower thread
clamp, lower thread
presser and lower thread
retainer.
Repair or replace the parts.
–
Rubbish, dust or thread
scraps present
Remove all rubbish, dust and thread scraps from the
lower thread trimmer.
–
Loose screws
Check for loose screws in
the upper thread trimmer,
lower thread trimmer and
work clamp lifter
mechanisms.
Securely tighten all screws.
–
Work clamp lifting
height setting
Check the work clamp
lifting height setting.
Change the settings of memory switch Nos. 001, 002,
003, 004.
*
If the work clamp lifting height is too high, the lower
thread trimming operation and the work clamp lifting
will become stiff, and the work clamp motor may go
out of step.
INSTRUCTION
MANUAL CD
Threading
Lower thread threading
Insert the bobbin correctly and pass the lower thread
through the bobbin case correctly.
*
If the bobbin is inserted back-to-front, it will spin
loosely and the work clamp motor may go out of
step.
INSTRUCTION
MANUAL CD
Lower thread tension
・
Reduce the lower thread tension.
* If the lower thread tension is much too strong, the
work clamp motor may go out of step.
・
Use memory switch No. 060 to reduce the work
clamp lifting speed setting to make the lifting speed
slower.
・
Buff this section A to reduce the
thread retaining resistance.
INSTRUCTION
MANUAL CD
*
*
Upper thread trimmer Upper thread trimmer
operation
Carry out opening timing adjustment for the upper
thread trimmer.
101
Presser lifter home
position
Presser lifter home position Adjust the presser lifter home position.
87
4022Q
Remove the shoulder
screw to check.
Lower thread
trimmer link A assembly
Lower thread
trimmer
connecting rod
4023Q
A
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 ...