Brother Z-8550A Owner's Manual

Z-8550A, 8560A 

67

9-1. Actuator position............................................... 67 

9-2. Adjusting the safety switch position.................. 68 

9-3. Thread tension spring....................................... 69 

9-4. Presser foot height ........................................... 70 

9-5. Feed dog height................................................ 70 

9-6. Feed dog angle................................................. 71 

9-7. Feed dog forward/back and   

sideways position ............................................. 71 

9-8. Feed amounts for reverse stitching and 

condense stitching............................................ 72 

9-9. Needle and feed timing..................................... 72 

9-10. Needle bar height ........................................... 73 

9-11. Needle zigzag forward/back position ............. 74 

9-12. Needle zigzag sideways position ................... 75 

9-13. Needle zigzag load ......................................... 76 

9-14. Needle and rotary hook timing ....................... 76 

9-15. Bobbin case holder bracket position .............. 77 

9-16. Adjusting the rotary hook lubrication amount.... 78 

9-17. Adjusting the presser foot floating amount 

(minute lifting amount) .................................... 79 

9-18. Adjusting the treadle....................................... 79 

9-19. Adjusting the quick reverse device 

(8550A-A31, 8560A)....................................... 80 

9-20. Adjusting the tension release during thread 

trimming (8560 only)....................................... 81 

9-21. Adjusting the position of the thread trimming 

cam (8560A only) ........................................... 82 

9-22. Adjusting the tension of the plate spring 

(8560A only) ................................................... 83 

9-23. Adjusting the thread trailing length after 

thread trimming (8560A only) ......................... 83 

9-24. Adjusting the thread wiper 

(8560A only, optional device) ......................... 84 

85

10-1. To continue sewing temporarily without   

applying grease .............................................. 85 

10-2. Applying grease ..............................................86 

10-3. Resetting the cumulative operating time.........87 

88

11-1. Precautions while carrying out adjustments ...88 

11-2. Control box internal configuration ...................89 

11-3. Description of fuses ........................................90 

11-3-1. Power supply P.C. board 

(fuses and fuse resistors) ...................90 

11-3-2. Main P.C. board 

(fuses and fuse resistors) ...................91 

11-4. Description of connectors ...............................92 

11-4-1. Connector positions............................92 

11-5. Troubleshooting ..............................................94 

11-5-1. Troubleshooting procedure ................94 

11-5-2. Diagnosis flowchart ............................95 

11-5-3. Remedy ..............................................97 

11-6. Wiring diagrams ............................................101 

103

12-1. Types ............................................................103 

12-2. Standard setting values ................................104 

12-3. Standard settings   

for treadle depression stroke ........................105 

107 

13-1. Installing the foot plug ...................................107 

13-2. Connectors....................................................108 

109 

114 

117