Summary of DC 3018
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Servicing manual dc3018 & dc3050
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Contents what to do when ....................................................................................................................... 1 - 3 face cover ........................................................................................................................................ 4...
Page 3: What to Do When
Condition cause how to fix reference 1. Skipping stitches 1. Needle is not inserted properly. 2. Needle is bent or worn. 3. Incorrectly threaded. 4. Needle or thread are inappropriate for fabric being sewn. 5. Sewing on stretch fabric. 6. Presser foot pressure is too weak. 7. Inappropriate needle ba...
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Condition cause how to fix reference 3. Breaking upper thread 1. Initial sewing speed is too fast. 2. Thread path is incorrect. 3. Needle is bent or dull. 4. Upper thread tension is too strong. 5. Needle size is inappropriate for fabric. 6. Needle eye is worn. 7. Needle hole in needle plate is worn ...
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Condition cause how to fix reference 6. Noisy operation 1. Backlash between shttle hook gear and lower shaft gear is too great. 2. Lower shaft gear is loose. 3. Inappropriatte belt tension. 4. Not enough oil. See mechanical adjustment “backlash (lower shaft gear)”. Eliminate the looseness. See part ...
Page 6: Service Access (1)
Setscrew (b) cap (a) face cover service access (1) ribs (e) hook (d) face cover to remove: 1. Remove the cap (a). 2. Remove the setscrew (b) and remove the face cover (c). To install: 3. Insert the hook (d) and ribs (e) of the face cover into the rear cover and tighten the setscrew, then attach the ...
Page 7: Service Access (2)
Bed cover setscrew (b) 2 setscrews (b) drop lever (a) bed cover (c) service access (2) to remove: 1. Set the drop lever (a) to the left and remove the 3 setscrews (b). Remove the bed cover (c). To install: 2. Set the drop lever (a) to the left and install the bed cover (c). Secure it in place with t...
Page 8: Service Access (3-1)
Service access (3-1) setscrew (c) setscrew (b) setscrew (a) setscrew (f) setscrew (e) setscrew (d) front cover setscrew (g) machine socket (connector on the pcb) power t r a n s f o r m e r (connector on the pcb) setscrew (h) to remove: 1. Remove the face cover and bed cover (see pages 7 and 8). 2. ...
Page 9: Service Access (3-2)
Service access (3-2) front cover feed balance dial knob machine plug setscrew (f) setscrew (g) hook 1. Unfasten the front and rear cover hooks and the bottom side hook as shown. 2. Pull the front cover to clear of the feed balancing knob. 3. Pull the front cover to clear of the machine socket and re...
Page 10: Service Access (4)
Setscrew (a) setscrew (b) rear cover service access (4) presser foot lifter setscrew (c) to remove: 1. Remove the front cover (see page 6 and 7). 2. Remove setscrews (a), (b) and (c), then remove the rear cover. * to remove the cover, detach the presser foot lifter section first, with the presser fo...
Page 11: Mechanical Adjustment
Presser bar height and alignment when the presser foot is raised, the clearance between the presser foot and the needle plate should be 6.0 mm. When the presser foot is lowered, the edge of the foot and the feed dog window on the needle plate should be parallel. 1. Remove the face cover and raise th...
Page 12: Mechanical Adjustment
Mechanical adjustment eccentric pin setscrew 3 x 4 needle plate hole 0.2 mm or more 0.2 mm or more a=b needle drop position set the stitch pattern at " "; the standard needle drop position should be at the center of the needle plate hole. When the needle swings in maximum zigzag width " ", the dista...
Page 13: Mechanical Adjustment
Mechanical adjustment setscrew (a) needle setting groove tip of hook meets right side of needle needle #14 hook race 1.6-2.0 mm upper edge of needle eye hook race unit needle bar height the distance between the upper edge of needle eye and the tip of the hook should be in the range of 1.6-2.0 mm whe...
Page 14: Mechanical Adjustment
Lower shaft gear mechanical adjustment when the machine is set the straight stitch pattern no.2 ( left needle position), the amount of ascending travel of the needle bar from its lowest position to the position where the tip of the hook meets the right side of the needle should be 3.25 - 3.55 mm. 1....
Page 15: Mechanical Adjustment
Preparation: 1. Remove the needle plate, bobbin holder, and bed cover, and replace the needle with the test pin (d). 2. Turn the power switch on, and select pattern " " (simploe zigzag). (maximum zigzag width) adjustment procedure: 1. Loosen the screws (a), (b), (c), then slightly tighten the hing s...
Page 16: Mechanical Adjustment
Mechanical adjustment backlash (between lower shaft gear and shuttle hook gear) jog the hook race back and forth to check rotary play. The standard play should be 0.8 mm (0.03") or less when the hook point is within the feed dog wodth. If play excess 0.8 mm, adjust as follows. Adjustment: 1. Remove ...
Page 17: Mechanical Adjustment
Mechanical adjustment the highest position of the feed dog should be between 0.8 to 0.9 mm from the surface of the needle plate when the pressure dial is set at "3" and the presser foot is raised. 1. Set the pressure dial at "3" and lower the presser foot. 2. Turn on the power switch. 3. Remove the ...
Page 18: Mechanical Adjustment
Mechanical adjustment 1. Remove the front cover (refer to page 6-7). 2. Turn on the power switch, select the pattern no. 2 and set the machine at the maximum zigzag width. 3. Turn the handwheel toward you slowly with your hand until the needle start to sewing. Loosen the setscrew and turn the upper ...
Page 19: Mechanical Adjustment
Mechanical adjustment thread (polyester sewing thread (#50 white)) @ pull the thread at a speed of approx. 110 mm/sec. In the direction of arrow. Shaft the standard tension should be 75 to 90 grams when the tension dial is set at "a" (auto), measured with a #50 white polyester thread being pulled at...
Page 20: Mechanical Adjustment
Stretch stitch feed balance when a stretch stitch pattern is sewn with the feed balancing dial position set at the standard setting mark " ", the stitch pattern should look like the one marked with a " " (a=b) in the diagram below. If forward and backward feeding is unbalanced (a.B or a,b), adjust a...
Page 21: Mechanical Adjustment
Mechanical adjustment threader knob hook needle hole replacing the needle threader cover (with the threader plate attached threader plate supporter (a) fig. 1 vertical adjustment threader position set plate fig. 3 fig. 2 x pin (b) setscrew (d) j 1. Push down the needle threader knob and pull the nee...
Page 22: Connector Diagram
Refer to the diagram for locating the connector posts to which each connectors should be connected. Connector diagram slide volume printed circuit board "f" zigzag width motor feed motor lamp buttonhole sensor upper shaft sensor machine socket (secondary) dc motor power transformer (primary circuit)...
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Printed circuit board "f" setscrew setscrew printed circuit board "a" to remove: 1. Remove the front cover (see page 9 ~ 10). 2. Unplug the connectors from the board "a". 3. Remove the 6 screws and remove board "a". Note: to disconnect the connectors: 1. Grasp the connector directly with your finger...
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To remove: 1. Remove the front cover unit (see page 6~7). 2. Unplug the slide volume connector. 3. Remove the four cs ring (a) and remove the side volume. To install: 4. To install the slide volume, follow the above procedure in reverse. * secure the lead wire on the board using the cs rings, as sho...
Page 25: Motor Belt Tension
Replacing ds motor and adjusting motor belt tension pressure 300g belt tension: 7~9 mm setscrews (2) setscrews (2) dc motor belt to remove: 1. Remove the front and rear covers (see page 6~8). 2. Remove the two setscrews, then remove the dc motor and belt. To install: 3. Lightly tighten the two screw...
Page 26: Replacing The Fuses
Setscrews (4) printed circuit board "a" printed circuit board "a" case replacing the fuses fuse holder fuse f2. Ac250v 3.15a f3. Ac250v 2.5a f1. Ac250v 2.5a fuse no. F1, f3 f2 part no. 000-144-605 000-182-904 replacing the fuses to remove: 1. Remove the front cover (see page 6~7). 2. Remove the four...
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Setscrew (b) machine socket replacing machine socket (unit) setscrew (b) replacing the machine socket to remove: 1. Remove the front and rear cover (see page 6 ~ 8). 2. Remove the two screws and remove the machine socket. To install: 3. To install the machine socket, follow the above procedure in re...
Page 28: Replacing The Transformer
Replacing the transformer to remove: 1. Remove the front cover (see page 6~7). 2. Remove the two setscrews and remove the transformer. Cut off the binder. To install: 3. To install the transformer, follow the above procedure in reverse. Note 1. Place the rear end of the transformer on the transforme...
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Replacing the zigzag width motor to remove: 1. Remove the front and rear cover (see page 9~11). 2. Remove the two setscrews and remove the zigzag width motor protector plate. Cut off the binder. 3. Remove the two zigzag rod setscrews. 4. Remove the two setscrews and remove the zigzag width motor. To...
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Replacing the feed motor to remove: 1. Remove the front cover and rear covers (see page 9~11). 2. Remove the snap ring (e-3). 3. Remove the two setscrews and remove the feed motor. Cut off the cord binder. Replacing the feed stitch motor snap ring (e-3) snap ring (e-3) feed motor setscrew (a) setscr...
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Adjusting buttonhole lever position to adjust the buttonhole lever guide: 1. Set the machine in buttonhole sensor adjusting mode. (see below. The led should display "h" or "l".) 2. Remove the face cover and loosen setscrew (a). 3. Lower the buttonhole lever. Loosen the setscrew and position the butt...
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Adjusting the bobbin winder switch setscrew switch fixing plate approx. 07. To 1.3 mm (bobbin winding) bobbin winder arm to adjust the bobbin winding switch 1. Remove the front cover (see page 6 - 7). 2. Set the bobbin winder arm in the sewing position and loosen the setscrew. Adjust the clearance b...
Page 33: Oiling
Oiling factory lubricated parts will provide years of household sewing without routine oiling, but you should still check for possible lubrication needs whenever servicing machines. Oil: use good quality sewing machine oil at the points (a, b, c, d, e, f,g,h,i,j & k) indicated by the black arrows. G...