Brother TZ1 B651 Guide

Industrial Sewing Machine Repairs
MADE EASYWith QWIK-Fix Teach Yourself Guides and Manuals
Brother TZ1 B651
QFBBR TZ1B651
Artizan 196 High Road Wood Green London ENGLAND N22 8HH
www.seweazi.com
BASIC REPAIRS &
ADJUSTMENTS

COPY RIGHTS ©2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic
of any of the data provided in any of their publications
QWIK-Fix-Publications™ READ FIRST
IMPORTANT NOTICE:
PLEASE NOTE:
If it is felt that carrying out any of the instructions listed in this manual
or CD are not within the capabilities of the person about to attempt the
adjustments you must seek the assistance of a qualified engineer.
QWIK-Fix-Publications DO NOT guarantee that the enclosed instructions
will solve any or all of the readers sewing machine breakdown problems
but advise that the information is a general guide to problem solving and
general adjustments only.

Qwik-Fix-Publications™
Brother TZ1 B651
BASIC REPAIRS & ADJUSTMENTS
CONTENTS SECTION
Repairs and Adjustments
Bobbin Base Replacement 1:1
Bobbin Base Retainer 1:3
Check Spring Adjustment 2:1
Check Spring Replacement 2:2
Feed Setting 3:1
Hook Timing 5:1
Hook lateral adjustment 5:2
Needle bar Settings 6:2
Needle Insertion 6:4
Needle Types/Sizes 6:5
Needles Using The Correct Type and Size 6:6
Needle Design 6:7
Stitch Formation 12:1
Tension (Lower) 13:2
Tension (Upper) 13:3
Thread Types/Sizes 14:1
Threading 14:3
Parts Description
Inner Machine UPPER 20:5
Inner Machine LOWER 20:6
QFBBR TZ1B651

TROUBLE SHOOTING FOR LOCKSTITCH SEWING MACHINES
BOBBIN AND BOBBIN CASE PROBLEMS Section
Bobbin case falls out 17:6
Bobbin case doesn’t fit in bobbin base 17:6
Bobbins don’t fit in bobbin case 17:6
BOBBIN WINDER PROBLEMS
Bobbin winder doesn’t drive 17:6
Bobbin winder thread uneven 17:6
Bobbin winder thread loose1 17:6
Bobbin winder thread tight1 17:6
Bobbins don’t fit winder 17:6
CHECK SPRING PROBLEMS
Check spring breaks easily 17:6
Check spring jams 17:6
FEED DOG PROBLEMS
Feed dog hits needle plate 17:7
Feed dog out of alignment 17:7
HOOK PROBLEMS
Hook jams 17:7
Hook area noisy 17:7
Hook timing keeps going out 17:7
Machine jams 17:7
NEEDLE PROBLEMS
Needle plate centre bends 17:7
Needles bend 17:7
Needles break 17:7
Needles fall out of needle bar 17:7
NEEDLE BAR PROBLEMS
Needle bar jams or seizes 17:7
PRESSER FOOT PROBLEMS
Presser foot jams up 17:8
Presser foot doesn’t lift high enough 17:8
Presser foot lifts too high 17:8
Presser foot doesn’t hold materials 17:8
STITCH FAULTS
Miss stitching 17:8
Stitch uneven 17:8
STITCH LENGTH PROBLEMS
Reverse stitch is too small 17:8
Stitches too small 17:8
Stitches too large 17:8
Stitches vary in size 17:8
THREAD TAKE UP LEVER PROBLEMS
Take up lever loose 17:9
TENSION PROBLEMS
Tension lower 17:9
Tension upper 17:9
Thread slips out of tension unit 17:9
Tension release doesn’t operate 17:9
Thread catches under materials 17:9
Thread loops under materials 17:9
THREAD PROBLEMS
Thread breaks 17:9
Thread frays or shreds 17:9
QFBBR TZ1 B651

COPY RIGHTS © 2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 1:1
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS :
Bobbin Base Replacement
1. Remove the presser foot,needle plate .feed and bobbin case .
2. Turn the hand wheel towards you to observe that there are 3 screws holding the GIB plate in place
Fig 1 . Remove all 3 screws which will release the gib plate.
3. Turn the hand wheel slowly towards you until you see the hook point Fig 2.
4. With the hook point in position as Fig 3 remove the BOBBIN BASE by tilting it from the bottom. Fig 4
5. With the new base in your left hand present it at an angle Fig 4 to the hook ensuring that it locates
into the bobbin base finger Fig 5.
6. With the bobbin base located correctly turn the hand wheel towards you until you can see where the
GIB plate has to be refitted Fig 1.
7. Fit the GIB plate into position and secure the 3 retaining screws. Put a spot of mineral oil around the
base and gib plate to help smooth running in.
8. Pull machine back into its normal working position and proceed to re -assemble the presser foot,
feed and needle plate. ©
9. Fit bobbin and bobbin case.
Now test the machine for stitching quality and adjust tensions if necessary
Side Views of the Hook and Bobbin Base
Fig 1 Fig 2 Fig 3
Fig 4 Fig 5
Gib Plate
Gib Screws
Hook Point
Bobbin Base
Retainer Slot
Hook Point
New Bobbin Base
Hook
Ba
se Retainer
Hook
Bobbin Base

COPY RIGHTS ©2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 1:3
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS :
Bobbin Base Retainer
1. Push the machine forward to expose the underside of the machine.
2. Depending on the style of base retainer it should be similar to FIG 1
But may have the retaining screw the opposite side to that in the fig.
3. To replace undo the screw holding the retainer and pull the retainer away from the machine.
4. When replacing it ensure you connect the bobbin base retaining finger in the slot of the bobbin base.
©
N.B
The retainer may be in a slightly different location to the one shown here but the slot in the
bobbin base will be exactly the same and the retainer will look very similar to the one shown
below.
Fig1
Base Retainer
Screw
Bobbin Base
Bobbin Base
Retaining Finger

COPYRIGHTS © 2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 2:1
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
Check Spring Adjustment
With the machine threaded and fabric under the presser foot turn the hand wheel towards you to
produce 3 or 4 stitches. STOP
Now continue to turn the hand wheel towards you until the thread take up lever Fig 1 is at its highest
point. STOP
The thread should have pulled the check spring down from its stop or rest point.
Continue turning the hand wheel slowly towards you until the eye of the needle has just entered the
fabric. STOP
The check spring should now be resting with no more tension on it.©
If it rests too early (before the eye has entered the fabric) slacken the tension unit screw Fig 2 and turn
the tension unit to the left about 1/8th of a turn and lock the screw back up.
If it rests too late (after the eye has entered the fabric) slacken the tension unit screw
Fig 2 and turn the tension unit to the right about 1/8th of a turn and lock the screw back up.
Continue to check and adjust as required.
Fig 1 Fig 2
FIG 3
Check spring
Thread Take Up Lever
Thread Take Up Lever
Screw position is to the right of the tension unit in the
head casting.
Decrease check
Tension Unit
Check Spring adjuster Increase check

COPY RIGHTS ©2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 2:2
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
:
Check Spring Replacement
1. Remove tension unit from the machine see FIG 2
2. To remove tension stud and discs complete loosen screw on tension unit see FIG 1
3. Remove the check spring from the back of the stud.
4. Fit a new spring.
5. Refit the stud to the unit tighten the stud screw FIG 1
6. Refit the tension unit to the machine. ©
7. To complete refer to the Check Spring Timing section
FIG 1 FIG 2
Thread Take Up Lever
Screw position is to the right of the tension unit in the
head casting.
Tension Unit
Tension stud retaining screw
Tension release
pin
Check Spring

COPY RIGHTS ©2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™3:1
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH ANY ADJUSTMENTS :
Feed Dog Settings
Feed dog height plays 2 important functions:
1- To feed materials as evenly as possible to give a regular stitch length.
2- To aid the upper thread take up lever to complete the draw of the thread before the
feed drops to return to feed forward again.
The optimum setting for the feed is as Fig 1.
To adjust :
Turn balance wheel towards you until the feed is at its maximum height. STOP.
©
Push machine back on its hinges and locate the feed height fork adjuster FIG 2
Slacken screw and move feed to desired position as FIG 1. Tighten screw and test
machine.
Fig 1 Fig 2
Adjuster Screw
Hook

COPY RIGHTS ©2004 QWIK-Fix-Publications™
At no time does QWIK-Fix-Publications or its licensees permit the copying in any format written or electronic of any of the data provided in any of their
publications
QWIK-Fix-Publications™ 5:1
Brother TZ1 B651
IMPORTANT !!!
SWITCH THE MACHINE OFF BEFORE PROCEEDING WITH THE ADJUSTMENTS
Hook Timing
1. Remove the needle plate, feed dog and presser foot.
2. Insert a new needle(Long groove to the front. facing you)
3. Set the needle bar alignment to the central position
4. Turn the hand wheel towards you(NEVER AWAY FROM YOU) until the needle reaches the bottom of its stroke. Fig
1STOP!
5. Continue turning the hand wheel towards you until the needle has lifted approximately 2/3mm from the bottom of its
stroke. Fig 2.STOP!
6. At this point the hook point should be in line with the centre of the needle Fig 3.If it is the hook timing is correct and
proceed to the next section 5:2 lateral hook adjustment. If the timing is incorrect continue as follows.
7. Slacken the screws that hold the hook to the drive shaft and “PINCH TIGHTEN” one screw.
8. Turn the hand wheel towards you until the needle reaches the bottom of its stroke Fig 1.STOP!
9. Continue turning the hand wheel towards you until the needle has risen 2/3mm from the bottom of its stroke Fig 2.STOP!
10. Rotate the hook so that the point aligns centrally to the needle Fig 3..ENSURE THAT THE AIR GAP BETWEEN THE
HOOK POINT AND THE NEEDLE IS NO MORE THAN 0.02mm Fig 4 (paper thickness) Tighten all screws. That’s how
easy the hook timing is….
11. Proceed to section 6:2 needle bar height adjustment.
Fig 1 Fig 2 Fig 3 (side view) Fig 4 (side view)
Needle bar
Needle
Bottom Of
Needle
bar Stroke
2/3mm Lift
Bottom
Timed
Hook
Eye of
Needle
Air Gap
Max
0.2mm
Hook
Point