Janome JW7630, Service Manual

Page 1: ...SERVICE MANUAL MODEL JW7630...

Page 2: ...G SYNCHRONIZATION 16 TENSION RELEASE MECHANISM 17 NEEDLE THREAD TENSION 18 STRETCH STITCH FEED BALANCE 19 REPLACEMENT AND ADJUSTMENT OF THE NEEDLE THREADER PLATE 20 CONNECTOR DIAGRAM 21 SELF DIAGNOSTI...

Page 3: ...13 2 Fabric not moving 1 Incorrect f d Height 2 f d Is in down position 3 Thread on bottom side of fabric is jammed up 4 Feed dog teeth are worn See mechanical adjustment feed dog height Raise the f...

Page 4: ...wing See mechanical adjustment needle drop position Change the needle See mechanical adjustment Clearance between needle and hook See mechanical adjustment Zigzag synchronization Guide the fabric gent...

Page 5: ...the face cover TO INSTALL 3 Insert the 2 ribs of the face cover into the rear cover and tighten the setscrew then attach the cap TOP COVER TO REMOVE 1 Remove the face cover 2 Remove the setscrew B C a...

Page 6: ...the base and the arm leg Install the base with the 4 setscrews A and the 2 setscrews BED COVER TO REMOVE 1 Set the drop lever to the left and remove the 2 setscrews C remove the bed cover TO INSTALL...

Page 7: ...ER TO REMOVE 1 Remove setscrew A and the needle plate 2 Remove the bed cover see page 4 3 Remove setscrew B and the Free arm cover TO INSTALL 4 Follow the above procedure in reverse Setscrew A Setscre...

Page 8: ...6 SERVICE ACCESS 4 BELT COVER TO REMOVE 1 Remove the setscrews A B and remove the belt cover TO INSTALL 2 Install the belt cover with the setscrews A and B Setscrew A Setscrew B Belt cover...

Page 9: ...he lead wire as this may damage the contact sleeve inside the connector TO INSTALL 4 To install the front cover follow the above procedure in reverse NOTES TO CONNECT THE CONNECTORS 1 Be sure that the...

Page 10: ...tscrews A B C and D then remove the setscrew E 3 Remove the rear cover To remove the cover detach the presser foot lifter section first with the presser foot lifter in the down position TO INSTALL 4 F...

Page 11: ...dog window on the needle plate should be parallel 1 Remove the face cover and raise the presser foot Loosen the setscrew to adjust the presser foot height 6 0 mm and the presser foot alignment 2 Tigh...

Page 12: ...m then check the needle drop position 2 If the needle drop position is not in the center of the needle plate hole when the straight stitch is selected or if the clearance between the needle and edge o...

Page 13: ...scending travel of needle from its left and lowest poosition 1 Remove the needle plate and bobbin holder 2 Turn on the power switch 3 Select the pattern simple zigzag Maximum zigzag width 4 Turn the h...

Page 14: ...set thestraight stitch pattern no 2 left needle position 3 Remove the bed cover 4 Turn the handwheel toward you and set the needle bar at the lowest position 5 Loosen the setscrews on the lower shaft...

Page 15: ...eel toward you and adjust the clearance between test pin and the point of the hook in the left and right needle position to 0 1 to 0 05 mm by moving the hook set plate up or down 3 Tighten the setscre...

Page 16: ...rew 3 Turn the lower shaft bushing eccentric bushing clockwise B if there is too much play in the hook race Turn the lower shaft bushing eccentric bushing counterclockwise A if there is too little pla...

Page 17: ...pressure dial at 3 and lower the presser foot 2 Turn on the power switch 3 Remove the bed cover 4 Turn the handwheel toward you to set the feed dog at the highest position 5 Loosen the setscrew A and...

Page 18: ...ard you slowly with your hand until the needle start to sewing Loosen the setscrew and turn the upper shaft shield plate in the direction of A If the swing point is higher than 7 5 mm B If the swing p...

Page 19: ...of A move the tension release plate 1 until it touches tension disk supporter In this condition tighten the set screw A 4 Raise the presser foot lifter and check the tension release mechanism 5 Set th...

Page 20: ...l is set at 4 measured with a 50 white polyester thread being pulled at aproximately 110 mm sec If the tension is outside the standard range adjust as follows ADJUSTMENT 1 Set the tension dial at 4 2...

Page 21: ...witch on and select the stitch pattern 2 Set the slit of the feed balancing dial to the standard setting mark on the front cover 3 Put a piece of paper under the presser foot and lower it Turning the...

Page 22: ...O REMOVE 1 Push down the needle threader knob and pull the needle threader plate A down to remove it see FIG 1 2 To install the needle threader plate line the groove up with the pin B and push it up t...

Page 23: ...ck them NOTE TO CONNECT THE CONNECTORS 1 Be sure that the color of each connector corresponds to the color of the connector post on the printed circuit board PCB to which it is connected 2 Position th...

Page 24: ...d PRELIMINARY TEST Turn on the power switch If any of following problems occur take the recmmended actions in the order they are shown The machine does not respond when the power switch is turned on 1...

Page 25: ...erse button within 2 5 seconds the machine automatically reverts to normal sewing mode Press needle up down button LED displays 02 for one second Press needle up down button LED displays 03 for one se...

Page 26: ...and lower the needle to its highest and lowest position When the needle is at the highest position LED displays LH When the needle is at the lowest position LED displays LH When the needle is halfway...

Page 27: ...rom the left to the right then return it to the left CORECT CONDITION When the speed control lever is at the left LED displays 00 The indicated value hexadecimal increases as you move the speed contro...

Page 28: ...shed turn off the power switch Press needle up down button LED indicates 12 for one swcond Press foot control LED indicates dc Machine runs at the speed set by the speed control lever Full left 80 100...

Page 29: ...achine socket and power transformer connectors pull them while pushing them toward the a board to unlock them TO INSTALL 4 To install follow the above procedure in reverse NOTE When installing board A...

Page 30: ...volume moves smoothly back and forth REPLACING PRINTED CIRCUIT BOARD F TO REMOVE 5 Remove the front cover unit 6 Unplug the printed circuit board F connector and remove the four CS rings 7 Remove the...

Page 31: ...ge 7 and 8 2 Remove the two setscrews then remove the DC motor and belt TO INSTALL 3 Lightly tighten the two screws 4 Put the motor belt on the pulley and adjust the belt deflection to about 7 to 9 mm...

Page 32: ...etscrews and lift off the cover on printed circuit board A 3 Remove the fuse Pry it out with a screwdriver TO INSTALL 4 Follow the above procedure in reverse NOTE 1 Replace the printed circuit board A...

Page 33: ...rear cover see page 7 and 8 2 Remove the two setscrews and remove the machine socket TO INSTALL 3 To install the machine socket follow the above procedure in reverse NOTE Pull out the cord in front of...

Page 34: ...To install the transformer follow the above procedure in reverse NOTE Place the rear end of the transformer on the transformer support Slide the two transformer wire tubes to the side of transformer...

Page 35: ...width motor follow the above procedure in reverse NOTE 1 The setscrew B of zigzag rod should be tightened to 5 7 kg of torque 2 Check to ensure that the upper shaft sensor mounted on the zigzag width...

Page 36: ...g E 3 3 Remove the two setscrews and remove the feed motor TO INSTALL 4 To install the feed motor follow the above procedure in reverse NOTE Adjust the stretch stitch patterns see page 22 REPLACING TH...

Page 37: ...D display changes from l to H 7 Next turn the adjusting screw to the right until the LED display changes from H to l 8 Check the LED When the clearance of the buttonhole foot is 1 4 mm the LED display...

Page 38: ...arm and the switch fixing plate to o 7 to 1 3 mm 3 Tighten the setscrew 4 Install the front cover TO CONFIRM Turn the power switch on The LED displays when the bobbin winder spindle is set the bobbin...

Page 39: ...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 GREASE Use white grease...