Janome 4300QDC Service Manual
  1. Manuals
  2. Brands
  3. Janome Manuals
  4. Sewing Machine
  5. 4300QDC
  6. Service manual

Janome 4300QDC Service Manual

Hide thumbs Also See for 4300QDC:
Table of Contents

Advertisement

Quick Links

See also: Instruction Book
First Edition: 19 September 2018
SERVICE MANUAL
MODEL: 4300QDC

Advertisement

Table of Contents
loading

Related Manuals for Janome 4300QDC

Summary of Contents for Janome 4300QDC

  • Page 1 First Edition: 19 September 2018 SERVICE MANUAL MODEL: 4300QDC...

  • Page 2: Table Of Contents

    INDEX What to do when ..........................1-3 Changing External Parts Face Cover ............................. 4 Free arm Cover ............................. 5 Front Cover ............................6-7 Rear Cover ............................. 8 Mechanical Adjustment Presser Bar Height ..........................9 Needle Drop Position ..........................10 Adjustment of Hook Timing ........................11 Adjustment of Needle Bar Height ......................

  • Page 3: What To Do When

    What to do when Condition Cause How to fix Reference 1. Skipping 1. Needle is not inserted properly. Insert the needle properly. Stitches 2. Needle is bent or worn. Change the needle. 3. Incorrectly threaded. Rethread. 4. Needle or thread are Use the recommended sewing needle inappropriate for the fabric and thread.
  • Page 4 Condition Cause How to Fix Reference 3. Breaking 1. Initial sewing speed is Start with medium speed. upper too fast. thread. 2. Thread path is incorrect. Use the proper thread path. 3. Needle is bent or dull. Replace with a new needle. 4.
  • Page 5 Condition Cause How to fix Reference 6. Noisy 1. Backlash between hook gear Eliminate the backlash. operation and lower shaft gear is too great. 2. Lower shaft gear is loose. Eliminate the looseness. 3. Inappropriate belt tension. See part removal and replacement P.

  • Page 6: Changing External Parts

    Changing ExtErnal Parts FaCE CovEr to remove: 1. Loosen the setscrew q and lift the face cover to disengage the rib on the inside. Remove the face cover w. to attach: 2. Follow the above procedures in reverse.

  • Page 7: Free Arm Cover

    Changing ExtErnal Parts FrEE arm CovEr to remove: 1. Loosen the setscrew q and w. Move the free arm cover e to the left. Remove the free arm cover. to attach: Follow the above procedures in reverse.

  • Page 8: Front Cover

    Changing ExtErnal Parts Front CovEr (1) to remove: 1. Remove the face cover and free arm cover (See page 8 and 9). 2. Remove the setscrews (A) q (2 pcs.). 3. Remove the setscrews (B) w (6 pcs.), back cover e. 4.
  • Page 9 Changing ExtErnal Parts Front CovEr (2) 1. Disengage the front cover and rear cover hooks. 2. Remove the front cover. to attach: Follow the above procedures in reverse.

  • Page 10: Rear Cover

    Changing ExtErnal Parts rEar CovEr To remove: 1. Remove the face cover and free arm cover (See page 4 and 5). 2. Remove the setscrews (A) q (5 pcs.). 3. Remove the setscrews (B) w (6 pcs.) and back cover. 4.

  • Page 11: Mechanical Adjustment

    mEChaniCal adjustmEnt PrEssEr bar hEight The distance between the bottom of the presser foot in up position and the needle plate should be 6.0 mm. 1. Remove the face plate and needle. 2. Lower the feed dog below the needle plate. Place a block 6 mm thick under the presser foot and lower the presser foot lifter w.

  • Page 12: Needle Drop Position

    mEChaniCal adjustmEnt nEEdlE droP Position Set the stitch pattern to “ ”. The standard needle drop position should be at center of the needle plate hole q. Select zigzag stitch “ ”, and set the stitch width at “5.0”. The clearance between the needle and the edge of the needle hole should be at least 0.2 mm on either side.

  • Page 13: Adjustment Of Hook Timing

    mEChaniCal adjustmEnt adjustmEnt oF hook timing The amount of ascending travel of the needle bar from its lowest position to the position ( ) where the tip of the rotary hook exactly meets the right side of the needle should be 3.25 to 3.55 mm. 1.

  • Page 14: Adjustment Of Needle Bar Height

    mEChaniCal adjustmEnt adjustmEnt oF nEEdlE bar hEight Before proceeding with this adjustment, check the hook timing (refer to page 11). The distance between the upper edge of the needle eye and the tip of the hook should be in the range of 1.6 to 2.0 mm when the tip of the hook timing meets right side of the needle in the left needle position ( ) as the needle ascends from its lowest position.

  • Page 15: Clearance Between Needle And Tip Of Rotary Hook

    mEChaniCal adjustmEnt ClEaranCE bEtWEEn nEEdlE and tiP oF thE rotary hook * The clearance between the needle and the point of hook should be –0.10 to +0.05 mm. adjustment procedure: 1. Remove the needle plate and bobbin holder. Attach the master needle. Turn the power switch on and set the zigzag width at maximum.

  • Page 16: Feed Dog Height

    mEChaniCal adjustmEnt FEEd dog hEight The highest position of the feed dog should be between 0.80 to 0.90 mm from the surface of the needle plate. 1. Lower the presser foot and turn the power switch on. 2. Turn the handwheel toward you to set the feed dog at the highest position. 3.

  • Page 17: Top Tension

    mEChaniCal adjustmEnt toP tEnsion The top tension should be between 65 to 80 gf when pulling the thread up in the direction of arrow. * Use polyester sewing thread #50 (White). * If it is not within the above limit, adjust as follows. 1.

  • Page 18: Stretch Stitch Feed Balance

    mEChaniCal adjustmEnt strEtCh stitCh FEEd balanCE to check: 1. Enter the self-diagnostic mode (see below). Attach the Satin stitch foot F. Place a fabric under the presser foot. Lower the presser foot. 2. Press the locking stitch button to start test sew, and check the results (the standard figure length of 5 pieces of figure 8 is 33 to 39 mm).

  • Page 19: Replacing The Electronic Components

    rEPlaCing thE ElECtroniC ComPonEnts CirCuit board-a ConnECtion notE: Do not disconnect the connectors by pulling on cord. To disconnect, grasp the connector, not the cord. q Printed circuit board F (white) !0 Power switch (WHITE) w Printed circuit board L2 (White) !1 DC Motor (white) e Program (Black) !2 Stitch width motor (green)

  • Page 20: Self-Diagnostic Test

    sElF-diagnostiC tEst Preparation: 1. Turn the power switch off. 2. Move the bobbin winder spindle to the left. 3. Raise the feed dog. 4. Set the speed control lever to the left. 5. Remove the presser foot and raise the presser foot lifter. 6.
  • Page 21 sElF-diagnostiC tEst stEP and ProCEdurE CorrECt Condition dEFECtivE Condition itEms t ChECk Turn on the power switch while Sewing lamp and LCD backlight lit. Sewing lamp does not lit. LCD displays “----”. LCD backlight does not lit. FunCtion oF simultaneously pressing the LCD does not display.
  • Page 22 sElF-diagnostiC tEst stEP and ProCEdurE CorrECt Condition dEFECtivE Condition itEms to ChECk Buzzer does not sound. LCD displays “05”. Move the presser foot lifter up and Presser foot symbol does down. PrEssEr When the presser foot lifer is lowered, not appear. Foot liFtEr If the result is correct condition, buzzer sounds and LCD displays...
  • Page 23 sElF-diagnostiC tEst stEP and itEms to ProCEdurE CorrECt Condition dEFECtivE Condition ChECk Attach the foot control to the LCD displays “08”. The foot control symbol machine. does not appear. Foot Depress the foot control as far as Buzzer does not sound. Control it goes, then release it.
  • Page 24 sElF-diagnostiC tEst stEP and ProCEdurE CorrECt Condition dEFECtivE Condition itEms to ChECk Turn the handwheel toward you to LCD displays “12”. Thread cutter motor does raise the needle bar at its highest not work. The thread cutter symbol will blink, and thrEad position.
  • Page 25 sElF-diagnostiC tEst Buzzer sounds after few seconds when the self-diagnostic test has been finished. The test result has been determined. CorrECt: Buzzer sounds and LCD displays “00” dEFECtivE: Caution buzzer sounds and LCD displays the defective part number. Refer to page 19 to 21 and fix the defective part. The defective part number.

  • Page 26: Circuit Board-A

    rEPlaCing thE ElECtroniC ComPonEnts CirCuit board-a to rEmovE: 1. Remove the front cover. (See pages 6 to 7) 2. Pull out connectors from the circuit board-A. 3. Remove the screws (4pcs.) and the circuit board-A. to attaCh: 1. Follow the above procedures in reverse. notE: Do not disconnect the connectors by pulling on cord.

  • Page 27: Driving Motor

    rEPlaCing thE ElECtroniC ComPonEnts driving motor to rEmovE: 1. Remove the front cover. 2. Remove the setscrews (2pcs.) and the driving motor and the belt. to attaCh: 1. Install the driving motor and the motor belt. Tighten them with setscrews (2pcs.) lightly. 2.

  • Page 28: Switching Regulator Unit

    rEPlaCing thE ElECtroniC ComPonEnts sWitChing rEgulator unit to rEmovE: 1. Remove the front cover and the rear cover. 2. Remove the setscrews A (3 pcs.) and the switching regulator. 3. Remove the setscrews B (4 pcs.). to attaCh: 4. Follow the above procedures in reverse. Switching regulator Setscrew A...

  • Page 29: Adjusting Buttonhole Lever Position

    mEChaniCal adjustmEnt adjusting buttonholE lEvEr Position to adjust thE buttonholE lEvEr guidE: 1. Enter the diagnostic test of buttonhole sensor mode. (See page 18 and 19. The LCD should display 03 and BH symbol.) 2. Remove the face cover (see page 4) and loosen the setscrew q. 3.

Table of Contents