background image

This sewing machine should only be used

by operators who have received the
necessary training in safe use beforehand.

The sewing machine should not be used

for any applications other than sewing.

Turn off the power switch at the following

times. The motor will keep turning even
after the power is switched off as a result
of the motor s inertia. Wait until the
motor stops fully before strating work.

When threading the needle.
When replacing the needle and

Bobbin.

When not using the machine and when

leaving the maching unattended.

Attach all safety devices before using the

sewing machine. If the machine is used

without these devices attached. Injury may

result.

Do not touch any of the moving parts or

press any objects against the machine while
sewing, as this may result in personal
injury or damage to the machine.

If an error occurs in maching, or if

abnormal noises or smells are noticed,
immediately turn off the power switch.
Then contact your nearest dealer or a
Qualitfied technician.

If the machine develops a problem.

contact your nearest dealer or a qualified
Technician

Turn off the power switch before carrying

out cleaning. The motor will keep turning even
after the power is switched off as a result of
the motor s inertia. Wait outil the motor stops
fully before starting work.The machine may
operate if the treadle is pressed by mistake,

CAUTION

Sewing

Cleaning

Maintenance and inspection

Be sure to wear protective goggles and

gloves when handling the lubricating oil, so
that no oil gets into your eyes or onto your
skin, otherwise inflammation can result.
Furthermmore, do not drink oil under any
circumstances, as it can cause vomiting and
diarrhoea. Keep the oil out of the reach of
children.

Maintenance and inspection machine

should only be carried out by a qualified
technician.

Ask you dealer or a qualified electrician to

carry out any maintenance and inspection of
the electrical system.

Turn off the power switch and disconnect

the power cord from the wall outlet at the
following thime.otherwise the machine may
operate if the treadle is pressed by mistake,
which could result in injury. However.The
motor will keep turning even after the power
is switched off as a result of the motor s
inertia. Wait until the motor stops fully before
staring work.

When carrying

out inspection.

adjustment and maintenance.

When replacing consumable prats such

as the rotary hook.

Any problems in machine operation which

result from unauthorized modifications to the
machine will not be covered by the warranty.

If the power switch need to be lefton when

carrying out some adjustment,be extremely
care full to observe all safety precautions.

When checking the rotary hook lubrication,

do not toutch moving pads such as the rotary
hook,needle and needle bar with your finger
or paper nor push them with other objects.
otherwise injury or damage to the machine
may result.

Use only the proper replacement pads as

specified by our company.

If any safety devices have been removed.

be absolutely sure to re-install them to their
original positions and check that they operate
Correctly before

using the machine.

Summary of Contents for ZJ2842-BD

Page 1: ......

Page 2: ......

Page 3: ... the range of 45 to 85 during use and no dew formation should occur in any devices Excessively dry or humid environments and dew formation may cause problems with correct operaton Avoid exposure to direct sunlught during Use Exposure to direct sunlight may cause problems with correct operation In the event of an electrical storm turn off the power and disconnect the power cord form the wall outlet...

Page 4: ......

Page 5: ...t be done For example the symbol at left means you must make the ground connection Machine installation should only be carded out by a qualified technician Be sure to connect the ground If the ground connection is not secure you run the risk of receiving a serious electric Shock Contact you dealer or a qualified electrician for any electrical work that may need to be done The sewing machine weighs...

Page 6: ......

Page 7: ...hen handling the lubricating oil so that no oil gets into your eyes or onto your skin otherwise inflammation can result Furthermmore do not drink oil under any circumstances as it can cause vomiting and diarrhoea Keep the oil out of the reach of children Maintenance and inspection machine should only be carried out by a qualified technician Ask you dealer or a qualified electrician to carry out an...

Page 8: ... Moving parts may cause injury Operate with safety devices Turn off main switch be fore threading changing bobbin and needle cleaning etc Moving parts may cause injury Operate with safety devices Turn off main switch be fore threading changing bobbin and needle cleaning etc Be sure to connect the ground If the ground connection is not secure you run the risk of receiving a seriois electric shock D...

Page 9: ......

Page 10: ......

Page 11: ......

Page 12: ...ber of stitches quick reference guide 26 7 SEWING 27 7 1 Sewing 27 7 2 Backtacking 27 8 THREAD TENSION 28 1 NAMES OF MAJOR PARTS 1 2 MACHINE SPECIFICATIONS 3 3 OPTINONAL PARTS 5 4 TABLE PROCESSING DIAGRAM 7 5 INSTALLATION 9 5 1 Installing the oil pan 10 5 2 Installing the machine head 11 5 3 Installing the knee lifter assembly 11 5 4 Installtion 13 5 5 Conexion de los cables 15 5 6 Installing the ...

Page 13: ...g the rotary hook 56 12 2 Replacing the upper thread tension assembly 59 13 TROUBLESHOOTING GUIDE 61 8 1 Adjusting the thread tension 28 8 2 Adjusting the presser foor pressure 29 9 CLEANING 30 10 STANDARD ADJUSTMENTS 31 10 1 Adjusting of the feed dog height 31 10 3 Adjusting the thread tension spring 32 10 4 Adjusting the needle and rotary hook timing 34 10 4 1 Needle rotary hook point gap 34 10 ...

Page 14: ...erse Stitching lever Sftitch length dial Needle plate Thread pillar Face plate Bobbin winder Machine pully Belt cover Reverse Stitching lever Sftitch length dial Needle plate Thread pillar Finger guard Thread take up cover Finger guard Thread take up cover ...

Page 15: ...2 ...

Page 16: ...3 ...

Page 17: ...4 ...

Page 18: ...or the rotary hooks in boxes Part code Part code Part code Part code Part code Part code Applicable model Applicable model Applicable model Applicable model Applicable model Applicable model He rotary hook point is reinforced to improve its durability This type is suitable for sewing materials that are hard to make loops on the surface like stretcht materials and that requiers making contact with ...

Page 19: ...read tension spring typr Thread take up spring strength Thread take up spring strength B4 177B B4 177B A B4 177B B Standard Weak Very weak Very weak Double Standard part at time of shipment2842 2845 2872 and 2875 Standard part at time of shipment2842 2845 2872 and 2875 Reference Tension spring force when spring height 12mm Standard Approx 49N Approx 5kgf Weak Approx 17 64N Approx 1 8kgf Very weak ...

Page 20: ... below A A 40 2 45 2 45 15 5 0 5 15 5 0 5 30 30 14 R 1 0 181 40 110 181 0 0 3 0 0 3 29 5 0 0 3 0 0 3 520 5 0 0 3 0 0 3 80 6 0 3 0 0 3 0 29 29 2 R10 2 R10 180 80 6 0 3 0 0 3 0 15 0 1 15 0 1 80 5 0 3 80 5 0 3 223 0 3 223 0 3 59 35 28 4 R20 4 R10 69 190 20 7 40 62 76 1200 181 R10 535 A A 35 35 174 174 A A 40 2 45 2 45 15 5 0 5 15 5 0 5 30 30 14 R 1 0 181 40 110 181 0 0 3 0 0 3 29 5 0 0 3 0 0 3 520 5 ...

Page 21: ...8 Kg Kg ...

Page 22: ... such as televisions radios or cordless telephones otherwise such equipment may be affected by electronic interference from the sewing machine The sewing machine should be plugged directly into an AC wall outlet Operation problems may result if extension cords are used Do not set up this sewing machine near other equipment such as televisions radios or cordless telephones otherwise such equipment ...

Page 23: ...10 ...

Page 24: ...lted back 1 Insert the knee lifter complying bar 2 Insert the two hinges into the holes in the machine bed 3 Clamp the hinges onto the rubber Cushions in the work table and then place the machine head onto the head cushions which are on top of the oil pan coners 4 Tap the pillow into the table hole Tap the pillow securely into the table hole If the pillow is not pushed in as faras it will go the m...

Page 25: ...e when the knee lifter plate is fully pressed 8 After adjustment is completes securely tighten the nut 2 Loosen rge nut 3 Turn the screw to adjust so that the amount of play in the knee lifter is approximately 2mm when the knee lifter plate is gently pressed 4 Securely tighten the nut 5 Loosen the nut 6 Turn the screw until the distance between the end of the screw and the knee lifter is approxima...

Page 26: ...13 1 Control box 2 bolts 5pcs 3 Spring washers 5pcs 4 Washers 5purchase 1 Control box 2 bolts 5pcs 3 Spring washers 5pcs 4 Washers 5purchase 5 Nut 6 Connecting rod 5 Nut 6 Connecting rod ...

Page 27: ...14 1 Power switch 2 Screws 2pcs 1 Power switch 2 Screws 2pcs 1 2 2 1 2 2 1 Operation panel 2 Screws 2pcs Use for tightening rear cover 1 Operation panel 2 Screws 2pcs Use for tightening rear cover ...

Page 28: ...15 ...

Page 29: ...connected The machine may operate if the treadle is depressed by mistake which could result in injury Do not connect the power cord until all cords have been connected The machine may operate if the treadle is depressed by mistake which could result in injury Be sure to connect the ground If the ground connection is not secure you run a high risk of receiving a serious electric shock and problems ...

Page 30: ...cable tie 1 otherwise may cause the cords to become disconnected which can cause problems with operation of the control box controles Bind the cords in such a way that the connector does not get pulled out All cords that come out from the control box should be secured to the cord holder 3 using the repeat cable tie 1 otherwise may cause the cords to become disconnected which can cause problems wit...

Page 31: ...and also after long periods of nn use Use only the lubricating oil Nisseki Sewing Lube 10 spectified by ZOJE Minimum lubrication speciflcations Pour lubricating oil into the oil 1 about once every six mouths Semi dry specifications Pour lubricating oil into the oil cover 1 about as often as grease is applied 1 Tilt back the machine head 2 Pour lubricating oil into the oil cover 1 until the oil lev...

Page 32: ...ng oil level drops below the bottom reference line 2 of the oil gauge window 1 be sure to add more oil 1 If the lubricating oil level drops below the bottom reference line 2 of the oil gauge window 1 be sure to add more oil ...

Page 33: ...that the direction of the machine pulley matches the direction of the arrow If the direction of rotary is reversed change the direction of ratation to the correct to the corret direction while referring to the instruction manual for the motor 1 Turn the machine pulley to move the needle bar to its highest position 2 Loosen the screws hold the needles with their long groove facting inward insert th...

Page 34: ...ng of the lower thread is completed the bobbin presser arm will return automatically If the thread cannot be wound on evenly loosen the screw and move the bobbin winder guide to the side where there is less thread Turn the adjustment screw to adjust the bobbin winding amount To increase the winding amount Tighten the screw To decrease the winding amount Loosen the screw Note The amount of thread w...

Page 35: ...tion 3 Return the rotary hook latch to its original position 4 Turn the machine pulley to rotary the ratary hook until the tension spring is visible 5 Pass the thread throungh slit A in the rotary hook and then pass it at under through tension spring 6 Pull out the thread to a length of approximately 50mm 7 Close the slide plates 4 Turn the machine pulley to rotary the ratary hook until the tensio...

Page 36: ... the cap into the rotary hook 5 Push latch of the rotary hook flat 6 Close the bed slide 1 Insert the bobbin into the cap so that the winding direction is as shown in the illustration 2 Thread the thread by one of the following methods in accordance with the shape of the cap being used 1 Pass the thread through slot A and under the tension spring 2 Pass the thread through slot B and C and then thr...

Page 37: ... The position of the finger guard is adjustable Be sure to lower it once threading has been completed Pass the thread correctly between the tension discs Pass the thread correctly between the tension discs Cotton thread Cotton thread Arm thread guide Arm thread guide Synthetic thread Synthetic thread Felt Felt Arm thread guide Arm thread guide If synthetic thread is used use the felt included in t...

Page 38: ...needle bar from moving otherwise damage to the machine may result NOTE If using this machine in place of a single needle machine remove the needle which is not being used In such cases do not use the procedures given below to stop the unused needle bar from moving otherwise damage to the machine may result NOTE 1000 Operate the stop lever after the needle has penetrated the material and has moving...

Page 39: ... 8 4 0 3 7 3 0 4 8 4 0 3 7 3 0 4 4 3 5 2 9 2 5 2 2 4 4 3 5 2 9 2 5 2 2 4 6 3 4 2 7 2 3 2 0 1 7 4 6 3 4 2 7 2 3 2 0 1 7 3 5 2 8 2 2 1 9 1 6 3 5 2 8 2 2 1 9 1 6 4 6 3 0 2 3 1 8 1 5 4 6 3 0 2 3 1 8 1 5 3 8 2 5 1 9 1 5 1 3 3 8 2 5 1 9 1 5 1 3 3 2 2 1 1 6 1 3 3 2 2 1 1 6 1 3 2 7 1 8 1 3 2 7 1 8 1 3 2 7 1 5 2 7 1 5 1 8 1 2 1 8 1 2 1 5 1 1 No of stitches No of stitches Sewing angle Sewing angle R To stop...

Page 40: ...e pulley by hand toward you until the lower threads come out onto the feed dog 2 Pull the lower threadds toward you and check that they pull out smoothly 3 Turn on the power switch 4 Depress the treadle to start sewing When the reverse stitching lever is pushed thecloth feed dirction will be reversed and when it is returned to its original position the feed direction will change back to normal Whe...

Page 41: ...too strong or lower thread tension too weak Lower thread tension The tension of the lower lower thread varies with the kind of cloth and thread and can be adjusted by turning the lower thread tension adjustment Screw Lower thread tension The tension of the lower lower thread varies with the kind of cloth and thread and can be adjusted by turning the lower thread tension adjustment Screw Less tensi...

Page 42: ...ed 1 Lower the presser foot 2 Adjust by turning the thread tension nut Upper thread tension After the lower thread tension has adjusted adjust the upper thread tension so that a good even stich is obtained 1 Lower the presser foot 2 Adjust by turning the thread tension nut Use Use Presser foot pressure Presser foot pressure Adjustment screw hight Adjustment screw hight For thin material For thin m...

Page 43: ...aps from inside the rotary hook 5 Replace the bobbin or the cap The following cleaning operations should be carried out each day in order to maintain the performance of this machine and to ensure a long service life Furthermore if the sewing machine has not been used for along period of time carry out the following clearing procedures before using it again The following cleaning operations should ...

Page 44: ...ate 4 Tighten the screw Lubrication 18 Lubrication the sewing machine according to the procedure on page 18 Lubrication 18 Lubrication the sewing machine according to the procedure on page 18 1 16 2 3 4 1 Check that the upper threads have been threaded correctly Refer to page 16 2 Check that the end of the needle is not broken If the end of the needle is broken the needle should be replaced 3 Lowe...

Page 45: ...tighten the nut Refer to page28 0 147 0 343 15 35 1 2 3 4 1 2 3 0 147 0 343 15 35 1 2 3 4 1 2 3 2 1 5 3 4 6 7mm 0 147 0 343 15 35gl 1 5 6 7 Less Less More More Less Less More More 9 8 2 6 Thread take up spring tension The standard tension for thread take up spring L andthread take up spring R is 0 147 0 343N 15 35g for both spring Thread take up spring L 1 Open the face plate 2 Loosen the screw 3 ...

Page 46: ...n the screws 1 2 3 Thread take up spring operation timing The standard operation take up spring L and thread take up spring R is the middle position within the operating range of the thread take up spring guide 1 Loosen the screw 2 Loosen the knob and then turn the left and right thread take up spring guided to adjust the tension 3 Tighten the screw and then tighten the knob 1 2 3 Thread take up s...

Page 47: ...hten screw NOTE 8 7 9 1 2 3 5 1 3mm 4 6 3 0 05mm 5 1 Tilt back the machien head 2 Loosen screws 3 Move the ratary hook base to the left or right so that the clearance between the needke and the rotary hook tip is 1 3mm 4 then turn the adjusting screw 6 to adjust so that the clearnce between the needle and the ratary hook tip 3 is 0 05mm 5 Aftering adjusting securely tighten screws and 1 2 3 5 1 3m...

Page 48: ...dle bar to its lowest position Reference line at the top of the needle bar must be aligned with the lower edge of the needle bar supporter at this time 4 Loosen the screw and move the needle bar up and down to adjust the height 5 Tighten the 8crew 6 Turn the machine pulley and check that the needle goes into the middle of the needle hole in the feed fog 2842 2872 1 2 3 4 5 6 2842 2872 Needle bar h...

Page 49: ...ip must be 1 1 5mm when the rotary hook tip is aligned with the center of the needle 15 Install the feed dog 16 Install the needle plate 7 Remove the needle plate 8 Remove the feed dog 9 Set the stitch length to either 2 appros 2mm or 3 appros 3mm on the scale depending on the model and spectifications of the machine Refer to the table 10 Turn the machine pulley to raise the needle bar by Hmm from...

Page 50: ...37 Stitch Length Stitch Length Needle bar height H Needle bar height H Insert the needle clamp all the way into the needle bar Insert the needle clamp all the way into the needle bar ...

Page 51: ...ok tip is 10 After adjustment is completed insert the needle bar clamp into the hole of the needle bar 1 Remove the needle plate 2 Remove the feed dog 3 Set the stitch length to eighter 2 approx 2mm on 3 approx 3mm or the sclale depending on the model and specifications of the machine refer to the table 4 Turn the machine pulley to raise the needle bar by Hmm from its lowest position refer to the ...

Page 52: ...39 ...

Page 53: ...2 Remove the thread from all points from the thread take up to the needle 3 Remove the needle and the bobbin 4 Use the lifting lever to lift the presser foot 5 Turn on the power switch 6 Run the machine at the normal sewing speed for approximately 1minute without sewing any naterial foliowing the same start stop pattern as when actually sewing 7 Place the lubrication amount check sheet 2 to the le...

Page 54: ...6 Check the position of the A mark on the machine pulley 7 Replace the belt cover 8 Install the needle 1 Remove the needle 2 Remove the belt cover 3 Tilt the machine head back and remove the timing belt 4 Turn the machine pulley until the A mark is aligned with the red dot 5 While holding the upper shaft so that it won t move align the mark in the lower belt pulley with the reference line in the a...

Page 55: ...The adjustment is good if the amount of oil shown at left is scattered during approximately 10 seconds After turning the lubrication adjustment screw to adjust the lubrication amount operate the machine for 5 10 minutes before checking the lubrication amount 1 Remove the needle 2 Remove the bobbin or the cap 3 Turn on the power 4 Instrt a piece of white paper into the left side of the rotany hook ...

Page 56: ... The adjustment is good if the amount of oil shown at lft is scattered during approximately 10 seconds After turning the lubrication adjustment screw to adjust the lubrication amount operate the machine for 5 10 minutes before checking the lubrication amount 1 Remove the needle 2 Remove the bobbin or the cap 3 Turn on the power 4 Instrt a piece of white paper into the left side of the rotany hook ...

Page 57: ... 5mm to the Inside of the needle center lines Securely tighten the screw Asjuarinf the return position Stop the machine while needle bar is at its highest position Turn off the power switch Set the stitch length to 2 on the scale Adjusting the forward and back position Loosen the screws and move the solenoid up and down to adjust so that the tips of the thread wiper are 0 3 0 5mm forward of the th...

Page 58: ...is too little the thread wiper may not be able to hook the threads depen ding on the kind of thread Set the thread wiper as close to the needles as possble provided that the threads will positively pass through the work Also check that the needle set screws will not contact the thread wiper Loosen the screw and turn the thread wiper supporter to adjust so that the cle arance between the tip of the...

Page 59: ...and and then remove the needle plate 3 Remove the holed screws and remove the movable knife 4 Remove the screws and remove the fixed knife If the knives becone blunt sharpen the fixed knives as shown The noving knife cannot be sharpened with an ordivary whetstone If it becones blunt replace it with a new one If the knives becone blunt sharpen the fixed knives as shown The noving knife cannot be sh...

Page 60: ...fe with your finger so that they are at the positions shown in the illustration 7 Tightcn the screw 11 1 Turn the machine pulley by hand untill the ooedres are pulled the way in the arrow direction 2 Lightly secure the moveble knife with screw Install the movable knife on the top of the bobbin thread clamp spring 3 Press down on the top of the movable knife and slide the movable knife Flrmly tight...

Page 61: ...above and adjust with nut as necessary If adjustmcnt is not possible replace the tension release wire If the thread slips out of the needle hole after thread cutting or if the tension disc remain open adjust as follows A If the thread slips out of the needle hole The tension release lever is not working properly during thread cutting 1 Press the thread trimming solenoid and turn the sewing maching...

Page 62: ... Adjustment method 1 Turn the machine pulley until the A mark is in line with the red dot 2 Turn the glisten parcel until the guild light is turned on 3 Turn the glisten parcel a little make sure the A mark is in line with the red dot when the needle is up stop position 1 Turn on the power 2 Stop the machine while the needle bar is at its hightest position 3 The pulley reference line should be vis...

Page 63: ...e sure the gap from the top of the needle plate to the bosom of the needle clamp is approximately 16mm 1 Turn the power on 2 Press the treadle and then release the treadle to neutral 3 Make sure the gap from the top of the needle plate to the bosom of the needle clamp is approximately 16mm ...

Page 64: ...ark on the machine pulley scale must be in line with the red dot on the machine head The permissible deviation of the T mark from the center of the red dot is 2mm 1 Remove the timming belt 2 Turn the machine pulley until the T mark is in line with the red dot 3 With the thread trimming solenoid depressed turnn the lower belt wheel in the arrow direction until it is hard to turn 4 Keep the machine ...

Page 65: ...6 Remove the presser foot 7 Remove the needle p ate 8 Remove the feet dog 9 Tilt back the machine head 1 Turn the machine pulley to move theneedle bar to its highest position 2 Remove the needle 3 Remove the slide plate 4 Remove the needle calmp 5 Raise the presser foot by using the presser foot lifter 6 Remove the presser foot 7 Remove the needle p ate 8 Remove the feet dog 9 Tilt back the machin...

Page 66: ...ft A A B B C C 1 Attach the needle clamp 2 Attach the needle 3 Attach the feed dog 2842 2845 1 Turn the machine pulley and check hat the needle goes into the middle of the needle hole in the feed dog 2 Loosen and align the needles so that the needles will fall in the centers of the needle holes in the feed dog 1 Attach the needle clamp 2 Attach the needle 3 Attach the feed dog 2842 2845 1 Turn the...

Page 67: ...hat the clearance between the needle and the rotary hook tip is 0 05mm After adjusting securely tighten screws and 4 Check the needle bar height Turn the machine pulley to move the needle bar the its lowest position and adjust so that reference line is aligned as shown in the machine head 5 Tilt back the machine head 6 Adjust the clearance between the needle and the rotary hook tip 1 Loosen screws...

Page 68: ...position 9 Attach the needle plate 10 Attach the presser foot 7 adjust the needle bar lift amount 1 Set the stitch length to eight 2 approx 2 mm or 3 approx3ram on the scale depending on the model and specifications of the machine Refer to the table on pages 33and34 2 turn the machine pulley to move the neelde ar to its lowest position and adjust so that reference line b is aligned as shown in the...

Page 69: ...ws 12 Turn the machine pulley to move the needle bar to its highest position 13 Remove the rotary hook 1 2 3 4 5 6 7 8 9 10 11 12 13 1 Turn the machine pulley to move the needle bar to its highest position 2 Remove the needle 3 Remove the slide plates 4 Raise the presser foot with the presser foot lifter 5 Remove the needle foot 6 Remove the needle plate 7 Remove the feed dog 8 Remove the opener 9...

Page 70: ...oo high tighten all three screws less than fully and then turn them all again to tighten them fully NOTE 1 2 3 34 b 1 Insert the new rotary hook into the mounting hole 2 Install the needles 3 While refering to pages 34 adjust so that the rotary hook tip is aligned with the center of the needle when the needle bar is raised from ist lowest poaltionI until reference line at the botton of the needle ...

Page 71: ...nd the opener is 0 2mm when the opener is pulled as far as it will go in the direction of the arrow 12 Tighten the set screw 13 Install the slide plates 14 Add 1 2 drops of oil to the left and right rotary hook races 15 Adjust the rotary hook Iubrication amount while referdng to page 39 9 Loosen the set screws and move the rotary hook up and down to adjust so that the clearance between the matary ...

Page 72: ...ust the tension of the thread take up spdng Refer to page32 3 Tighten the screw 4 Close the face plate 1 2 3 1 2 32 3 4 1 Openthefaceplate 2 Loosen the screw 3 Loosen the screw and then remove the upper thread tension assembly 1 Install the new upper thread tension assembly and tighten it with the screw 2 Adjust the tension of the thread take up spdng Refer to page32 3 Tighten the screw 4 Close th...

Page 73: ...60 22 24 14 22 24 14 1 1 2 2 3 3 8 13 13 16 11 23 22 13 13 16 11 23 22 ...

Page 74: ...ce the needle Is the needle properly installed If it is incorrect install the needle correctly Is the machine properly threader If it is incorrect thread the thread correctly Is the rotary hook properly Iubricated If the oil level is below the lower reference line in the oil sight glass add more oil Is dust or thread in the rotary hook Clean the rotary hook Is the upper thread tension too strong o...

Page 75: ...62 2842 2872 2842 2872 4 4 5 5 6 6 2 6 2 6 13 13 16 21 2 5 13 13 16 21 2 5 32 16 25 20 21 16 25 20 21 ...

Page 76: ...perly threaded If it is incorrect thread the thread correctly Is the thread take up spring operationg range too small Adjust the operationg range of the thread take up spring Is the needle thread tension and bobbin thread tension too low Adjust the upper and lower thread tension Is the bobbin scratched If the bobbin is damaged smooth it with an oiled grindstone or replace it Is the machine properl...

Reviews: