- •SAFETY INSTRUCTIONS
- •1. Safety indications and their meanings
- •2. Notes on safety
- •3. Warning labels
- •CONTENTS
- •1. SPECIFICATIONS
- •1-1. SPECIFICATIONS
- •1-2. Standard thread tension
- •1-2-1. Measuring tension
- •2 . MECHANICAL DESCRIPTIONS
- •3. DISASSEMBLY
- •3-1. Covers
- •4 . ASSEMBLY
- •4-1. Thread trimmer mechanism (1)
- •5 . ADJUSTMENT
- •5-1. Adjusting the needle bar height
- •5-26. Adjusting the tension of the upper shaft timing belt
- •5-31. Adjustment of inner clamping device
- •6. TROUBLESHOOTING
- •7 . OPTIONAL PARTS
- •8 . ELECTRIC MECHANISM
- •8-14-1. Troubleshooting flowchart
- •8-14-2. Problem solution and measures

SERVICE MANUAL | |
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Please read this manual before using the machine.
Please keep this manual within easy reach for quick reference.
ELECTRONIC LOCKSTITCH BAR TACKER ELECTRONIC LOCKSTITCH BELT LOOP BAR TACKER ELECTRONIC LOCKSTITCH PATTERN TACKER ELECTRONIC LOCKSTITCH BUTTON SEWER

This service manual is intended for
Carefully read the “SAFETY INSTRUCTIONS” below and the whole of this manual to understand this product before you start maintenance.
As a result of research and improvements regarding this product, some details of this manual may not be the same as those for the product you purchased.
If you have any questions regarding this product, please contact a Brother dealer.
SAFETY INSTRUCTIONS
1. Safety indications and their meanings
This service manual and the indications and symbols that are used on the machine itself are provided in order to ensure safe operation of this machine and to prevent accidents and injury to yourself or other people.
The meanings of these indications and symbols are given below.
Indications
DANGER The instructions which follow this term indicate situations where failure to follow the instructions will almost certainly result in death or severe injury.
The instructions which follow this term indicate situations where failure to follow the CAUTION instructions could cause injury when using the machine or physical damage to equipment
and surroundings.
Symbols
This symbol ( ) indicates something that you should be careful of. The picture inside the triangle indicates the nature of the caution that must be taken.
(For example, the symbol at left means “beware of injury”.)
This symbol ( ) indicates something that youmust not do.
This symbol ( ) indicates something that you must do. The picture inside the circle indicates the nature of the thing that must be done.
(For example, the symbol at left means “you must make the ground connection”.)
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2. Notes on safety
DANGER
Wait at least 5 minutes after turning off the power switch and disconnecting the power cord from the wall outlet before opening the face plate of the control box. Touching areas where high voltages are present can result in severe injury.
CAUTION
Environmental requirements
Use the sewing machine in an area which is free from sources of strong electrical noise such as
Sources of strong electrical noise may cause problems with correct operation.
Any fluctuations in the power supply voltage should be within 10% of the rated voltage for the machine. Voltage fluctuations which are greater than this may cause problems with correct operation.
The power supply capacity should be greater than the requirements for the sewing machine’s electrical consumption.
Insufficient power supply capacity may cause problems with correct operation.
The pneumatic delivery capability should be greater than the requirements for the sewing machine’s total air consumption.
Insufficient pneumatic delivery capability may cause problems with correct operation.
The ambient temperature should be within the range of 5 C to 35 C during use.
Temperatures which are lower or higher than this may cause problems with correct operation.
The relative humidity should be within 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 operation.
Avoid exposure to direct sunlight 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 from the wall outlet. Lightning may cause problems with correct operation.
Installation
Machine installation should only be carried out by a qualified technician.
Contact your Brother dealer or a qualified electrician for any electrical work that may need to be done.
The sewing machine weighs more than 52 kg. The installation should be carried out by two or more people.
Do not connect the power cord until installation is complete, otherwise the machine may operate if the foot switch is depressed by mistake, which could result in injury.
Hold the machine head with both hands when tilting it back or returning it to its original position. Furthermore, after tilting back the machine head, do not push the face plate side or the pulley side from above, as this could cause the machine head to topple over, which may result in personal injury or damage to the machine.
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 with correct operation may also occur.
All cords should be secured at least 25 mm away from any moving parts. Furthermore, do not excessively bend the cords or secure them too firmly with staples, otherwise there is the danger that fire or electric shocks could occur.
Install the belt covers to the machine head and motor.
If using a work table which has casters, the casters should be secured in such a way so that they cannot move.
Be sure to wear protective goggles and gloves when handling the lubricating oil and grease, so that they do not get into your eyes or onto your skin, otherwise inflammation can result.
Furthermore, do not drink the oil or eat the grease under any circumstances, as they can cause vomiting and diarrhoea.
Keep the oil out of the reach of children.
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CAUTION
Sewing
This sewing machine should only be used by opera- | If using a work table which has casters, the casters |
tors who have received the necessary training in safe | should be secured in such a way so that they cannot |
use beforehand. | move. |
The sewing machine should not be used for any | Attach all safety devices before using the sewing |
applications other than sewing. | machine. If the machine is used without these |
Be sure to wear protective goggles when using the | devices attached, injury may result. |
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machine. | Do not touch any of the moving parts or press any |
If goggles are not worn, there is the danger that if a | objects against the machine while sewing, as this |
needle breaks, parts of the broken needle may enter | may result in personal injury or damage to the |
your eyes and injury may result. | machine. |
Set the needle to the needle up stop position before | If an error occurs in machine operation, or if abnormal |
turning off the power. | noises or smells are noticed, immediately turn off the |
If this is not done, the wiper may strike the needle, | power switch. Then contact your nearest Brother |
which might cause the needle to break. | dealer or a qualified technician. |
Turn off the power switch at the following times, | If the machine develops a problem, contact your |
otherwise the machine may operate if the foot switch | nearest Brother dealer or a qualified technician. |
is depressed by mistake, which could result in injury. |
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When threading the needle |
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When replacing the needle and bobbin |
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When not using the machine and when leaving the |
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machine unattended |
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Cleaning
Set the needle to the needle up stop position before | Be sure to wear protective goggles and gloves when | ||||
turning off the power. |
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| handling the lubricating oil and grease, so that they | ||
If this is not done, the wiper may strike the needle, | do not get into your eyes or onto your skin, otherwise | ||||
which might cause the needle to break. |
| inflammation can result. | |||
Turn off the | power switch | before | carrying out | Furthermore, do not drink the oil or eat the grease un- | |
der any circumstances, as they can cause vomiting | |||||
cleaning, otherwise the machine may operate if the | |||||
and diarrhoea. | |||||
foot switch is | depressed by | mistake, | which could | ||
Keep the oil out of the reach of children. | |||||
result in injury. |
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Maintenance and inspection
| Maintenance and inspection of the sewing machine | If the power switch and air need to be left on when |
| should only be carried out by a qualified technician. | carrying out some adjustment, be extremely careful to |
| Ask your Brother dealer or a qualified electrician to | observe all safety precautions. |
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| carry out any maintenance and inspection of the | Hold the machine head with both hands when tilting it |
| electrical system. | back or returning it to its original position. |
| Set the needle to the needle up stop position before | Furthermore, after tilting back the machine head, do |
| turning off the power. | not push the face plate side or the pulley side from |
| If this is not done, the wiper may strike the needle, | above, as this could cause the machine head to |
| which might cause the needle to break. | topple over, which may result in personal injury or |
| Turn off the power switch and disconnect the power | damage to the machine. |
| Use only the proper replacement parts as specified | |
| cord from the wall outlet at the following times, | |
| otherwise the machine may operate if the foot switch | by Brother. |
| is depressed by mistake, which could result in injury. | If any safety devices have been removed, be abso- |
| When carrying out inspection, adjustment and main- | lutely sure to |
| tenance | and check that they operate correctly before using |
| When replacing consumable parts such as the ro- | the machine. |
| tary hook | Any problems in machine operation which result from |
| Disconnect the air hoses from the air supply and wait | unauthorized modifications to the machine will not be |
| for the needle on the pressure gauge to drop to “0” | covered by the warranty. |
| before carrying out inspection, adjustment and repair |
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| of any parts which use the pneumatic equipment. |
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3. Warning labels
The following warning labels appear on the sewing machine.
Please follow the instructions on the labels at all times when using the machine. If the labels have been removed or are difficult to read, please contact your nearest Brother dealer.
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Safety devices
Eye guard
Finger guard
3 High temperature warning displayThread
Thread
Frame side cover, etc.
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5
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 with correct operation may also occur.
Direction of operation
Thread
Frame side cover
2670Q
Eye guard
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Thread | Belt cover | ||
solenoid cover | |||
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| Finger guard |
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| 2737Q |
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