Brother International LT2-B845 Instruction Manual - Multi - Page 42

TROD !ILI:SHOOTING Gt.:11W Be sure to check the following before calling an authorized service station. Problem 1. Sewing machine pulley doesn't turn. Where to check (page) • Is a breaker or fuse blown? • Is the power cord disconnected? 2. Needle thread and bobbin thread break. Ill 3. Seams don't match. 4. Skipped stitches 5. Poor thread tightening • Is the needle tip bent? • Is the needle tip blunt? • Is the needle properly installed? (p.13) • Is the machine properly threaded? (p.16 and 17) • Is the rotary hook properly lubricated? (p.11) • Is dust or thread in the rotary hook? • Is the presser foot pressure too weak? (p.18) • Is the feed dog too low? (p.32) • Is the bobbin scratched? • Is the V-belt tension too low? (p.8) • Is the needle tip bent? • Is the needle properly installed? • Is the presser foot pressure too weak? (p.18) • Is the machine properly threaded? (p.16 and 17) • Is the needle tip blunt? • Is the sewing speed too fast? • Is the thread take-up spring operating range too small? (p.21) • Is the needle thread tension and/or bobbin thread tension too low? (p.19) • Is the bobbin scratched? • Is the machine properly threaded? (p.16 and 17) 6. Broken needles • Is the needle tip bent? • Is the needle tip blunt? • Does the needle pass the center of the needle hole in the feed dog? Caution If problems 2 to 6 above are not due to the cause on the right, check the needle and feed timing, or the needle and rotary hook timing. If the problem persists, turn the power off and consult your dealer. - 37 -