Janome MC8900 QCP Service Manual
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Janome MC8900 QCP Service Manual

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SERVICE MANUAL
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PARTS LIST
MC8900 QCP

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Summary of Contents for Janome MC8900 QCP

  • Page 1 SERVICE MANUAL & PARTS LIST MC8900 QCP...

  • Page 2: Table Of Contents

    INDEX CHANGING EXTERNAL PARTS Face cover ............................1 Top cover .............................1 Belt cover ............................2 Machine base ............................3 Base cover ............................3 Bed cover ............................3 Free arm cover ............................4 Front cover ............................5 Rear cover ............................6 REPLACING ELECTRONIC COMPONENTS Printed circuit board A .........................7 Printed circuit board F .........................8 Switching power supply unit ........................9 Driving motor .............................10...

  • Page 3: Changing External Parts

    Changing External Parts (1) 　 Face cover Face cover Setscrew A To remove: 1. Remove the setscrews A. Remove the face cover. To attach: 1. Follow the above procedure in reverse. Top cover Top cover Setscrew B Carrying handle To remove: 1.

  • Page 4: Belt Cover

    Changing External Parts (2) 　 Belt cover Setscrew A Belt cover To remove: 1. Remove the setscrews A. Setscrew B 2. Loosen the setscrews B and C. 3. Remove the belt cover. To attach: 1. Follow the above procedure in reverse. Setscrew C Setscrew C...

  • Page 5: Machine Base

    Changing External Parts (3) Setscrew A Machine base Setscrew A Machine base To remove: 1. Remove the setscrews A. 2. Remove the machne base. To attach: 1. Follow the above procedure in reverse. Setscrew A Setscrew A Base cover Setscrew B Base cover Setscrew B To remove:...

  • Page 6: Free Arm Cover

    Changing External Parts (4) Needle plate release lever Free arm cover Needle plate To remove: 1. Remove the machine base and base cover (see page 3). Press the needle plate release lever to remove the needle plate. Free arm cover Setscrew 2.

  • Page 7: Front Cover

    Changing External Parts (5) Front cover Setscrew A Setscrew A To remove: 1. Remove the top cover, belt cover, base cover, machine base and free arm cover (see pages 1-4). 2. Loosen the setscrews A (inside of the machine base). Setscrew B 3.

  • Page 8: Rear Cover

    Changing External Parts (6) Setscrews A Rear cover Rear cover To remove: 1. Remove the top cover, mahine base, base cover and free-arm cover (see pages 1, 3 and 4.) 2. Remove the setscrew A. Setscrews B 3. Remove the setscrew B. Setscrews C Rear cover 4.

  • Page 9: Replacing Electronic Components

    Replacing electronic components Printed circuit board A Setscrew NOTE: Do not disconnect the connectors by pulling on cord. To disconnect the connectors, grasp the connector, not the cord. To remove: 1. Remove the front cover. 2. Grasp the connector directly with your fingers and pull. Do not pull the lead wire, as this may damage the contact sleeve inside the connector.

  • Page 10: Printed Circuit Board F

    Replacing electronic components Printed circuit board F o remove: 1. Remove the front cover (see page 5). 2. Disconnect the connectors from the circuit board A (see page 7). 3. Remove the CS rings. 4. Remove the setscrews, and the circuit board F. To attach: CS rings 1.

  • Page 11: Switching Power Supply Unit

    Replacing electronic components Switching power Switching power supply unit supply connector Cord guide plate Setscrew A To remove: 1. Remove the belt cover, the top cover and the front cover (see page 1, 2 and 5). 2. Loosen the setscrew A. Remove the cord guide plate. 3.

  • Page 12: Driving Motor

    Replacing electronic components Driving motor To remove: 1. Remove the belt cover, the top cover and the front cover (see pages 1, 2 and 5). 2. Remove the motor belt. 3. Disconnect the driving motor connector from the printed circuit board A. 4.

  • Page 13: Thread Tension Unit

    Replacing electronic components Setscrew A Thread tension unit To remove: 1. Remove the belt cover and the top cover (see pagesf 1 and 2). 2. Remove the front cover (see page 5). 3. Disconnect the Solenoid 1 thread tension release connector from the printed circuit board A (see page 7).

  • Page 14: Mechanical Adjustment

    Mechanical adjustment Feed dog height When the foot pressure dial is at “7” and the presser foot A is lowered, the highest position of the feed dog should be 0.80 to 0.90 mm from the surface of the needle plate. Adjustment 1: 1.

  • Page 15: Needle Drop Position

    Mechanical adjustment Needle drop position When the straight stitch is selected, the needle should be positioned in the center of the needle plate hole. When the needle drop position is set at "0.0" and "9.0", the clearance between the side of the needle and the needle hole should be 0.2 mm or more.

  • Page 16: Presser Bar Height

    Mechanical adjustment Presser bar height The clearance between the presser foot and the surface of the needle plate should be 6 mm when the presser foot is raised. The presser foot (zigzag foot A) should be pararell to the slot of the feed dog teeth when attached. To adjust: 1.

  • Page 17: Hook Timing

    Mechanical adjustment Hook timing The amount of ascending travel of the needle bar from its lowest position to the position (Needle drop position 0.0) where the tip of the rotary hook exactly meets the right side of the needle should be 3.70 to 4.00 mm (Needle drop position 0.0) To adjust: Needle #14...

  • Page 18: Needle Bar Height

    Mechanical adjustment Needle bar height The distance between the upper edge of the needle eye and the hook race should be in the range of 1.6 to 2.0 mm when the tip of the hook meets right side of the needle in the needle drop position "0.0" as the needle ascends from its lowest position.

  • Page 19: Clearance Between Needle And Tip Of The 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 -0.1 to +0.05 mm. Adjustment 1 1. Remove the top cover (see page 2). Needle plate hole 2.
  • Page 20 Adjustment 2 1. Remove the bed cover (see page 3). 2. Turn the power switch ON, and select the zigzag stitch pattern 9. Setscrew C Setscrew A Adjust the stitch width at its maximum (9.0). 3. Remove the presser foot, needle plate and bobbin holder.

  • Page 21: Presser Bar Lifter Switch Position

    Mechanical adjustment Presser bar lifter switch position adjustment To check: 1. While pressing the needle up/down and lock stitch buttons, turn the power switch on. 2. Turn the jog dial to select "06. Sensor". Presser foot lifter Bobbin Press the confirm button. switch 3.

  • Page 22: Backlash Between Hook Drive Gear And Lower Shaft Gear

    Mechanical adjustment Backlash between hook drive gear and lower shaft gear The rotary play of the hook should be 0.8 mm or less when the tip of rotary hook is within the width of feed dog. 1. Remove the base cover and bed cover (see page 2 and 3). 2.

  • Page 23: Upper Shaft Shield Plate Position

    Mechanical adjustment Upper shaft shield plate position When the machine is set for zigzag stitch, the needle should start to swing 7.2 to 8.2 mm above the surface of the needle plate. To check: 1. Attach the needle #14. 2. While pressing the needle up/down and lock stitch Needle #14 buttons, turn the power switch on.

  • Page 24: Upper Thread Tension

    Mechanical adjustment Upper thread tension The standard upper thread tension should be 75 to 90 grams when pulling the thread (while polyester thread size 50) at the speed of 110 mm/sec with the tension at "AUTO" (Be sure the presser foot is lowered). 1 Set the thread tension dial to "AUTO".

  • Page 25: Needle Threader Plate

    Mechanical adjustment Needle threader plate If the hook of the threader plate is damaged, change or adjust the part as follows: To remove: 1 Push down the needle threader knob and pull the needle threader plate (A) down to remove it (see Fig.

  • Page 26: Thread Drawing Lever

    Mechanical adjustment Thread drawing lever The standard height of the thread drawing lever from the surface of bobbin holder should be in the range of 5.5 – 6.0 1. Remove the presser foot, the needle plate and the Thread drawing lever bobbin holder.

  • Page 27: Upper Feed Dog (1)

    Mechanical adjustment Upper feed dog (1) The clearance between the upper feed link shaft and upper feed lower shaft should be 2.5 mm when the upper feed adjusting dial is set to "0". To check: 1 Remove the belt cover and base cover (see page 1 and 2).

  • Page 28: Upper Feed Dog (2)

    Mechanical adjustment Upper feed dog (2) The clearance between the dual feed foot and upper feed dog should be 4 mm when the stitch length is set at "0". * Check the upper feed dog (1) (see page 26) before this adjustment. To check: 1.

  • Page 29: Upper Feed Dog (3)

    Mechanical adjustment Upper feed dog (3) The tip of the needle height should be 0 to 1 mm above the surface of the needle plate when the toe of the dual feed foot touch the needle plate. To check: Fig. 2 1.
  • Page 30 To adjust: Setscrew select straigh stitch (D1). 1. Turn the power switch on and (Be sure that the machine is not locked.) Turn the drop feed lever to drop the feed dog. Press the adjusting key and set the stitch length at "0". Turn the upper feed adjusting dial to set the dial at "0".

  • Page 31: Buttonhole Lever Adjustment

    Mechanical adjustment Buttonhole lever adjustment To prepare: 1. While pressing the needle up/down and lock stitch buttons, turn the power switch on. The LCD screen display "Factory adjust", then adjusting screen will appear. 2. Turn the jog dial to select "06. Sensor". Press the confirm button.

  • Page 32: Thread Cutter

    Mechanical adjustment Thread cutter The distance between the end of thread cutter plate slit and the edge of moving cutter should be in the range of 0.4 to 1.2 To check: 1. Remove the bed cover and free arm cover (see page 3, 4). 2.

  • Page 33: Solenoid Position Adjustment

    Mechanical adjustment Solenoid position adjustment When the tension disk is closed, the clearance between the plunger and the end of yoke should be 2.0 mm. TOP VIEW [To check] 1. While pressing the needle up/down and lock stitch buttons, turn the power switch ON. The LCD screen display “Factory adjust”, then adjusting screen will appear.

  • Page 34: Stretch Stitch Feed Balance

    MECHANICAL ADJUSTMENT Stretch stitch feed balance Adjust the stretch stitch balance dial C at the setting mark D. The measurement of five of test patterns should be in the range of 33 to 39 mm as shown. To adjust: 1. While pressing the needle up/down and lock stitch buttons, turn the power switch on.

  • Page 35: Needle Plate Switch

    Mechanical adjustment Needle plate switch Fig. 1 To check and adjustment: Needle plate sensor 1. Prepare the needle plate and the needle plate for straight stitch. 2. Insert the needle plate base plate under the fixed cutter ◎ spacer and the slide plate positioning plate. Press the mark to attach the needle plate.
  • Page 36 To check: While pressing the needle up/down and lock stitch buttons, turn the power switch on. The LCD screen display "Factory adjust", then adjusting screen will appear. Turn the jog dial to select "06.Sensor". Needle plate attached: 2. Be sure that "Needle plate" indicates Bobbin "ZZ Plate"...

  • Page 37: Diagnosis Test

    DIAGNOSIS TEST NOTE: 1. Be sure that the power switch is turned off when replacing parts. 2. The language on the LCD is English only. Preparation 1. Shift the bobbin winder spindle to the right. 2. Slid the drop feed lever to the right (away from you) to raise the feed dog. 3.
  • Page 38 STEP 1 (LCD DISPLAY) [CORRECT CONDITION] [FAULTY CONDITION] 1) LCD display and LED blink at 1 The step 1 screen does not appear. second interval. LCD or LED does not blink. 2) Sewing light turns ON. –REMEDY– Press the reverse stitch button to Replace circuit boards F or A.
  • Page 39 STEP 4 (SPEED CONTROL LEVER AND FOOT CONTROL) SLIDE VOLUME [FAULTY CONDITION] [CORRECT CONDITION] The display does not change or indicates Move the speed control lever slowly. incorrect value. The display shows when the lever is: At the left end: 000-008 At the right end: 1012-1024 –REMEDY–...

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Mc8200 qc

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