Singer 591UTT User manual

SINGER
591 UTT
Service
Manual
From the library of: Superior Sewing Machine & Supply LLC

CONTENTS
Page No.
Description 1
UnderbedThread Trimmer 2-15
Principal Parts 2-3
DriveSystem of Thread Trimmer 2
Pullingand TrimmingUnit 2
Tension Releaseand MovableSlack Thread Regulator 3
Descriptionof TrimmingOperation 3-6
Timing and Setting 6-15
Adjustment of NeedleStop Positions 6-8
Timing—Actuation of Trimmer Solenoid 8
Timing —Completion of Actuation of Trinuner Solenoid 8-9
Setting of Trimmer Solenoid 9
Setting of Stationary Knife 9
Setting of Thread Puller 9-10
Adjustment of Pressure of Thread Puller Against Stationary Knife 10-11
Timing and Setting of Thread Puller Action Cam 11-12
Timing of Tension Release Action Cam 12
Setting of Thread PuUerAction Cam AdjustingPlate 13
Adjustment of Gap Between Tension Discs 13-14
Timing of Tension Release 14
Adjusting the Length of Needle Thread End 14-15
Adjustment of Thread Wiper 15
Back Tack Device 16-21
Principal Parts 16-17
Description of BackTacking Operation 18
Setting and Adjustment
of BackTack Device 18-21
Setting of Back Tack Solenoid 18
Setting of Feed Rock Shaft DrivingFrame 19
Setting
of Feed Rock Shaft DrivingFrame Action Shaft and Collar 19
Setting of Feed Rock Shaft DrivingFrame Action Lever 19-20
Feed Rock Shaft DrivingFrame Spring Tension 20
Setting of Feed Rock Shaft Driving Frame Stopper Spring 20
Setting of Push Button Switch 20
Adjustment of Push Button SpringTension 21
Cords and Connections 21
* A Trademark of THE SINGER COMPANY
Copyright© 1981 THE SINGER COMPANY
All Rights Reserved Throughout the World
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DESCRIPTION
An electro-mechanical underbed thread trimming unit, which is an integral part of the machine, is incorporated in the "B"
variety machines.
The machine is driven by a needle positioner motor, and its sensor and controlbox relay the electronic commands to the
built-in solenoids of the machine.
The needle and bobbin threads are trimmed below the throat plate after the sewing operation.
A threadwiper "Wipes" the needle thread to proper positionfor startingthe next sewing operation.
In addition to the under bed thread trimming unit, a back tackingsystem is incorporatedin the "G"
variety machines. The
automatic back tack switch and control box relay the electronic commandsto the built-insolenoidfor automatic back tacking
at start and at end of stitching. The push button switch provided adjacentto the needle barpermitsback tacking in the midst
of the sewing operation.
This manual should be used in connection with the Service Manual Form U3208 for the regular 591 machine. It informs
especially regarding the operation and maintenance of the underbed thread trimmer and back tacking device and their drive
systems.
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UNDERBED THREAD TRIMMER
PRINCIPAL PARTS
Drive System of Thread Trimmer
THREAD PULLER ACTION LEVER LINK
THREAD PULLER ACTION LEVER
THREAD PULLER
THREAD PULLER ACTION CAM ADJUSTING PLATE
TENSION RELEASE ACTION PLATE
STATIONARY
KNIFE
/WVW/
ROTATING
HOOK SHAFT
THREAD PULLER BRACKET
THREAD PULLER ACTION
CAM FOLLOWER
TENSION RELEASE ACTION CAM
THREAD
PULLER
ACTION
CAM
THREAD PULLER ACTION PLATE
Fig. 1
Pulling and
Trimming Unit
STATIONARY KNIFE
Fig. 2
THREAD PULLER
TENSION RELEASING WIRE
TRIMMER SOLENOID
THREAD PULLER ADJUSTING BLOCK
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Tension Release and Movable Slack Thread Regulator
SLACK THREAD REGULATOR
ACTION PLATE
MOVABLE SLACK
THREAD REGULATOR
Fig. 3
DESCRIPTION OF THE TRIMMING OPERATION
1. When the foot treadle is returned to its neutral position
upon completion of the sewing cycle, the machine
stops approximately Smm (.118") beyond the bottom
dead center of the needle (Fig. 5, hook point in the
loop of needle thread) when the sensor plate A (red)
reaches a point shown in Fig. 6.
2. Heeling the foot treadle will start the machine to run
at the trimming speed (200 r.p.m).
SENSOR PLATE A
TENSION RELEASING
CAM
TENSION RELEASING WIRE
Fig. 4
Fig. 5
Fig. 6
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The trimmer solenoid is energized when the sensor
plate B (yellow) reaches a point shown in Fig, 7.
SENSOR PLATE B
Fig. 7
When the cam follower on the thread puller action plate slips into the recessed portion of the thread puller action cam
adjustingplate, the thread puller is activated to move through the loop (Fig. 8) to a point shown in solid line in Fig.9,
and the needle and bobbin threads are positioned as shown also in Fig. 9. Simultaneously, the thread puller action plate
pushes the tension release action plate making its pin ride on the tension release action cam. Immediately when the pin
rides on the tension release action cam,the electroniccommandrelayedfrom the sensorplate C (yellow,Fig. 10) cuts off
the current supply to the trimmersolenoid. The above motion makes the tension releasing camrotate untiljust beforethe
tension discs are released.
Fig. 8
NEEDLE
THREAD
BOBBIN
THREAD
©
Fig. 9
n
SENSOR PLATE C
Fig. 10
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5. As the needle thread is cast off the rotating hook, it
catches on the hook portion of the thread puller.
(Fig. 11)
6. The tension release action plate pin reaches the inclina
tion on the tension release action cam and starts re
leasing the tension discs immediately after the needle
thread catches on
the thread puller.
Fig. 11
7. While the above takes place,the camfolloweron the thread pulleraction plate reachesthe inclinationon the thread puller
action camand the thread puller beginsto pull the bobbin and needlethreads toward the stationary knife.
8. The bobbin and needle threads are severed when the
cutting edge of the thread puller closes in against the
cutting edge of the stationary knife. (Fig. 12 and 13)
9. When the threads are trimmed, the spring biased
tension release action plate moves back to its rest
position disengaging its pin from the tension release
action cam and thus completesits function of releasing
and holding the needle thread tension open.
10. The trimmer and tension releasing mechanisms return
to their rest positions upon completion of the
trimming operation and the machine stopsin the upper
needle position. When the sensor plate D (yellow)
reaches a point shown in Fig. 14.
200 type - Approximately 1mm (.039") before take-
up leverreachesits upper dead center.
300 type — Take-up leverat its upper deadcenter.
SENSOR PLATE D
Fig. 14
CUTTING EDGE OF
THREAD PULLER
Fig. 12
CUTTING EDGE OF
STATIONARY KNIFE
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11. Upon completion of the trimming operation, the
thread wiper makes a swivelling movement to place
the needle thread in proper position for starting the
next sewing operation.
TIMING AND SETTING
When checking the operation of the trimmermechanism by manual actuation of the mechanisms.
a. Be sure to tum machine pulley over toward front of machine.
b. Push thread pulleraction plate toward cam when take-upleveris almost at its lower dead center.
NOTE: The thread puller may strike the needle and damage itself and the needle unless the thread puller action plate it
pushed toward the cam as described above since the rotatinghook shaft makes two revolutions against onecycle
of the needle bar.
Be sure to check that the machine is correctly adjusted before making adjustments to the trimmer mechanism. (Refer to
ServiceManual Form U3208 for regular 591 machine).
Check and adjust the trimmer mechanism in the order instructed in this manual since it is interlocked with many other area.
Adjustment of Needle Stop Position
When checking and making adjustments of needle stop positions, be sure to disconnect the trimmer and wiper connectors
from the control box.
Needle Stop Positions
a. Lower Needle Position
The lower needle position is approximately 3mm (.118") beyond the bottom dead center ofthe needle. This 1st position
does not call for absolute accuracy and minor adjustments may be made ifthe threads cannot be properly trimmed dueto
skip stitching.
b. Upper NeedlePosition
The upper needle position of the 200 type machine is approximately 1mm (.039") before the take-up lever reaches its
upper dead centerand the upper needle position of the 300 type machine is when the take-up lever is at itsupper dead
center.
Adjust upper needle positionas accurately as possible by running andstopping machine several times to checkfor correct
position.
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Adjustments
AH sensors are correctly timed andset before leaving the factory. If, however, this timing or setting has been disturbed and
retiming or resetting becomes necessary, adjust bycorrectly positioning the sensor plates.
1. The positions of the sensor plates (for upper and lower needle positions and for controlling the trimmer solenoid) in
relation to the sensor set screw should be as shown in Fig. 15. To adjust the position of a sensor plate, loosen screw on
end of the sensorandturn sensor plateasrequired,then tightenthe screw.
SENSOR PLATE C —
(TRIM. SOLENOID "OFF")
SENSOR SET SCREW
Fig. 15
39'
SENSOR SET SCREW
SENSOR PLATE D
(UPPER NEEDLE POS.)
149'
SENSOR PLATE A
(LOWER NEEDLE POS)
SENSOR PLATE B
(TRIM.SOLENOID "ON")
Position sensor on hub of machine pulley so that its second set screw (set screw which appears immediately after the first
set screw when sensor is rotated over toward the operator) is alignedwith the second set screw of the machine pulley and
firmly tighten the two set screws. (See Fig. 16)
ALIGN SET SCREW
MACHINE PULLEY
MACHINE PULLEY SET SCREW
SENSOR SET SCREW
Fig. 16
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3. Use sensor retainer supplied withthe machine andbe sure it is correctly secured in position.
Note: The sensor plate for upper needle position should not be reset inorderto solve the problem of tension releasing
mechanism not being released when needle stopsin the upper needle position.
Thisadjustment
should bemadeby resetting the sensorunit on the hub of machine pulley asinstructed below.
a. Loosen the two set screws holding the sensor unit and while holding the sensorwithonehand,turn machine pulley
slightly over toward the front of machine.
b. Hold sensorin this position and temporarily tighten the first screw.
c. Run machine and checkwhether the tension releasing mechanism is released when the needle stops in the upper
position. Repeat above, if necessary.
d. Firmly tighten both first and second set screws.
Timing — Actuation of Trimmer Solenoid
The trimmer solenoid is actuated when the take-up lever reaches a point lOmm (.394") before its lower dead center. The
timing of this actuationis controlled by the sensor plateBin the sensor unit. (Referto item3 underDescription of Trimming
Operation).
Timing — Completion of Actuation of Trimmer Solenoid
The current supply to the trimmersolenoid is cut off completing its actuation when the tension release action plate pinis in
the
range fi shown in Fig. 17.Thistimingis controlledby the sensorplate Candwhenadjustmentisnecessary, reset thissensor
plate.
Turn machine pulley until the clearance between tension release action plate pin and tension release action cam is approxi
mately 1mm(.039") (Fig. 17) and whileholdingthe machinepulley in this position, set sensorplate C asshownin Fig. 18.
TENSION RELEASE ACTION CAM
TENSION RELEASE ACTION
PLATE PIN
APPROX. 1.0 mm
Fig. 17
Fig.
18
SENSOR PLATE C
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Note: This timing must be adjusted as accurately as possible. If timing is too fast, the thread puller will not operateto trim
the threads. If the
timing is slow, it will cause the take-up lever to slow downon its upward strokeandstop anywhere
before or beyond the correct upper stop position.
Setting of Trimmer Solenoid
The trimmer solenoid is correctly set on the machine before
the machine leaves the factory. If, however, this setting
has been disturbed and resetting becomes necessary, adjust
as instructed below. (Fig. 19)
To adjust setting, loosen the two screws holding the
trimmer solenoid bracket and move bracket as required to
set:
Angle — Plunger on trimmer solenoid should be aligned
with trimmer solenoid link.
Stroke — Clearance between flange of plunger and sole
noid should be 4mm
(.157")
Setting of Stationary Knife
The stationary knife should be set so that there is a
clearance of 0.3mm (.012") between its cutting edge and
the right side of the feed dog. (Fig. 20)
To adjust, loosen the two screws holding the stationary
knife and move knife to the left or right as required, then
firmly tighten the screws.
When replacing the feed dog, be sure this clearance is
provided as instructed above.
Note: If the clearance mentioned above is too large, the
length of thread end under the fabric will become
longer.
Setting of Thread Puller
When the thread puller is in its rest position, its rightedge
should be parallelwith the edge
of bed asshownin Fig.21.
TRIMMER SOLENOID LINK
PLUNGER
BRACKET
SCREW
TRIMMER SOLENOID
Fig. 19
FEED DOG
STATIONARY KNIFE
O.Srnm
Fig. 20
THREAD PULLER
Fig. 21
MUST BE
PARALLEL
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Tomakethisadjustment, loosen the set screw andturn eccentric bushing, asrequired, then tightenthe set screw. (Fig.22)
ECCENTRIC BUSHING SET SCREW
THREAD PULLER ACTION
LEVER SET SCREW
CKMAAAA/'
Fig. 22
ECCENTRIC BUSHING
Thethreadpullerbracketshouldbe set so that the tip of thread puller will passby the centerof the needle. (Fig.23)
Oncompoundfeed
M/CS. stitchlengthshouldbe set at 10SP.I. when making thischeck.
To adjust loosen the two screws holding the thread puller bracket and move bracket as required,then firmlytighten the two
screws.
NEEDLE
MOUNTING SCREW HOLES
Fig. 23
Note: When replacing the feed dog with a new one, use only Singer part. Further,the feeddogshouldnot be setlowerthan
the standard height because it may cause the thread puller to interfere withthe underside of the feed dog.
Adjustment of Pressure of Thread Puller Against Stationary Knife
The pressure of thread puller against stationary knife should be held as light as possible and never be greater than actually
required. (The force required to actuate the thread puller when applied to point A, Fig. 24 should be approximately 1kg.)
10
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To adjust the pressure, loosen set screws holding the eccentric studand thread pulleraction lever and move pressure adjusting
block as required by turning the eccentric stud. Tighten set screws.
ECCENTRIC STUD
THREAD PULLER ADJUSTING BLOCK
ECCENTRIC STUD SET SCREW
THREAD PULLER ACTION LEVER SET SCREW
Fig. 24
Timing and Setting of Thread Puller Action Cam
The clearance between the highest point of thread puller action camand follower portion of thread pulleraction plate should
be 0.5 mm (.020") (Fig. 25)
To make this adjustment, follow the adjustment procedure noted hereunde.r.
1. Loosen the two set screws holding the thread puller action cam and the two tension release action cam set screws.
2. Tum thread pulleractioncamuntil its highest pointislocatedopposite the follower on threadpulleractionplateand slide
thread puller action cam to the left or right as required to provide the 0.5mm (.020") clearance specified above, then
temporarily tighten the set screws.
3. Push tension release action cam lightly against the right end of thread puller action cam and temporarily tighten the set
screws.
4. Firmly tighten the set screws when thread puller action cam has beencorrectlytimedasinstructedinthe following para
graph.
THREAD PULLER
ACTION PLATE
0.5mm
TENSION RELEASE
ACTION CAM
THREAD PULLER
ACTION CAM
TIMING
MARK
Fig. 25
Fig. 26
(FOR DROP FEED MACHINE)
11
Fig. 27
(FOR COMPOUND FEED MACHINE)
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The timing mark on the thread puller action cam must align withthe timing mark on the thread puller action plate when
distance from top of needle bar coimecting stud, needle bar on its downward stroke, to underside of arm at needle end is
66.6mm (2.622") in the case ofdrop feed 200type machine and 69.2mm (2.724") inthe case ofdrop feed 300type machine.
(Figs.25 and 26)
On compound feed machines, the timming mark on the thread puller action cam must align with the timming markon the
thread puller action plate whendistance fromtop of needlebar connecting sud,needlebar on its down stroke,to lowerend of
needle bar frame is 79.7mm (3.138")in the case of 200type machine and 77.0mm (3.031")inthe case of300type machine.
(Figs. 25 and 27)
Adjust timing as instructed below.
1. Loosen the two set screwsholding the thread puller action cam.
2. Tum machine pulley over toward front of machine until the needle bar is beyond upper dead center and descends to
the point shown in Fig. 26 or 27.
3. Tum thread puller action cam until its timing mark is aligned withthe timing mark onthe thread puller action plateand
while holding the threadpulleractioncam pressed lightly against the tension release actioncam, firmly tighten the two
set screws.
Timing of Tension Release Action Cam
The tension release action cammust be set so that the tension release action plate pin is disengaged fromthe tension release
action cam immediately after thread trimmingis completed. (Fig. 28)
To make this adjustment, follow the instmctions noted below.
1. Loosen two set screwsand tum the tension releaseaction cam as required.
2. When correct position has been located, firmly tighten the two set screws while holding the tension release action cam
pressedlightly against the thread puller action cam.
THREAD PULLER
(MOVABLE KNIFE)
STATIONARY KNIFE
TENSION RELEASE
ACTION CAM
TENSION RELEASE
ACTION PLATE PIN
Fig. 28
Note: When replacing the feed dog with a new one, be sure to check the timing of tension release action cam and readjust
if necessary.
12
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Setting of Thread Puller Action Cam Adjusting Plate (Timing (start of activation) of thread puller)
The thread pulleraction cam adjusting plate should be set so that its step portion will align with the follower on the thread
puller action plate when distance from top of needle bar connecting stud to underside of arm at needle end, needle bar in
ascent,is 69.5mm (2.736") in the caseof drop feed 200 type machine and 72.5mm(2.854") in the case of drop feed 300 type
machine. (Figs. 29 and 30)
On compoundfeed machines, the thread pulleraction camadjusting plateshouldbe setso that its step portion will align with
the follower on the thread puller action plate when distance from top of needle bar connecting stud to lower end of needle
bar frame, needle bar in ascent, .is 83.2mm (3.276")inthe case of 200type machine and 78.3mm (3.083")inthe case of300
type machine. (Figs. 29 and 31)
This timing will be acceptable for the majority of threads, however in some instances it may be necessary to depart slightly
from this standard setting.
THREAD PULLER ACTION
CAM ADJUSTING PLATE
THREAD PULLER
ACTION PLATE
Fig. 29
rg)
Fig. 30
(FOR DROP FEED MACHINE)
Fig. 31
(FOR COMPOUND FEED MACHINE)
Adjustment of Gap Between Tension Discs (Figs. 32 and 33)
The gap between the two tension discs should be 0.8 —1.0mm (.032 —.039") whilethe tension is released. This gap willnot
increase even if the presser bar is pushed up as far as it willgo.
Adjust gap as instructed below.
1. Check that the tension (complete) is correctly set in position.
2. Loosen the set screw holding the tension releasing cam bracket and move bracket to the left or right as requireduntil
desired gap has been achieved.
3. Hold bracket in this position and firmly tighten the set screw.
13
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TENSION RELEASING
CAM
\
TENSION RELEASING
CAM BRACKET
TENSION RELEASING CAM
BRACKET SET SCREW
I©,? ' /
TENSION RELEASING WIRE
CONNECTING PLATE
J
Fig. 32
TENSION RELEASING WIRE
TENSION RELEASING WIRE
GUIDE TUBE CLAMPING PLATE
Fig. 33
Timing of Tension Release
To adjust the timing of releasing the tension when presser bar is raised by hand or by knee operation, loosen the two tension
releasing wire connecting plate screws and move connecting plate upor down as required.
If timingislate, moveconnectingplate downward.
If timingisfast, move connecting plateupward.
Firmly tighten the two screws when correct timing has been achieved. (Fig. 32)
The tension discs should begin to separate, or release the needle thread tension, just before the thread puller begins to make
its return stroke to trim the threads.
When adjustingthis timing:
1. Check timing of tension release action cam. (Refer to Timing of Tension Release Action Cam adjustment procedure)
2. Loosen the two screws holding the tension releasing wire guide tube clamping plate and move guide tube to the left or
rightasrequired and firmly tightenthe screws. (Fig.33)
(To advance timing, move guide tube to the right and to retard the timing, move guide tube to the left.)
Adjusting the Length of Needle Thread End
To adjust the starting length of needle thread end with
pre-tension, loosen the pre-tension cap screw and turn pre
tension cap clockwise to shorten the thread end, and turn
pre-tension cap counterclockwise to lengthen the thread
end. (Fig. 34)
14
SHORTER
LONGER
Fig. 34
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Note; When using the pre-tension to adjust the length of needle thread end, every care must be taken not to causeill effect
to sewing performance.
To adjust the starting length of needle thread end with movable slack thread regulator, loosen the two set screwsholding the
slack thread regulator action plate and move action plate up or down as required, then firmly tighten the set screws.(Fig. 35)
(Move the slackthread regulatoraction plate up to shorten and down to lengthen the needlethread end)
SHORTER
LONGER
SLACK THREAD REGULATOR
ACTION PLATE
Fig. 35
Adjustment of Thread Wiper
The thread wiper does not require minute adjustment however care should be taken so that
1. The wiper wiU not interfere with the right hand side of the presser foot when presser foot is raised.
2. there is at least 1.0mm (.039") clearance between wiper and point
of needle when wiper is operated when needle is in
upper stop position.
15
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BACK TACK
SOLENOID LINK
APPROX.
0.7mm
PLUNGER
BACK TACK
SOLENOID
FEED ROCK SHAFT
DRIVING FRAME ACTION
SHAFT BRACKET (LEFT)
.o f^EED ROCK SHAFT
FRAME ACTION SHAFT COLLAR DRIVING FRAME ACTION [
SHAFT BRACKET (RIGHT)
FEED ROCK SHAFT DRIVING
FRAME ACTION SHAFT
5.0mm STROKE
BACK TACK SOLENOID
BRACKET
FEED ROCK SHAFT
DRIVING FRAME
HINGE PIN (LEFT)
BACK TACK SOLENOID BRACKET SCREW
Fig. 36
FEED ROCK SHAFT
DRIVING FRAME
ACTION LEVER
STOPPER
1 .OiiitB CLEARANCE
FEED ROCK SHAFT
DRIVING FRAME
ACTION LEVER
'V\ !,| „i
V
1.5mm
FEED ROCK SHAFT
DRIVING FRAME
FEED ROCK SHAFT
DRIVING FRAME
HINGE PIN (RIGHT)
"O
z
o
>
r-
TJ
>
30
H
CO
DO
>
O
7^
>
O
o
m
<
o
m
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PRINCIPAL PARTS (Continued)
FEED REVERSE LEVER HINGE STUD CRANK
FEED ROCK SHAFT
• DRIVING FRAME
I ACTION LEVER
STOPPER
FEED ROCK SHAFT DRIVING
FRAME ACTION LEVER
SCREWDRIVER
FEED ROCK SHAFT DRIVING FRAME ROLLER
FEED ROCK SHAFT DRIVING FRAME SPRING
STOPPER SPRING REGULATING SCREW
17
\
FEED REVERSE LEVER HINGE
STUD CRANK CONNECTING LINK
! FEED ROCK SHAFT
DRIVING FRAME
FEED ROCK SHAFT DRIVING
FRAME STOPPER SPRING
LOCK NUT
Fig. 37
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DESCRIPTION OF BACK TACKING OPERATION
Backtacking with the back tack deviceis done by means of a built-in back-tack solenoid.
When an electronic command from the control box(for automatic back tacking) and/orthe push button switch is relayed to
the back-tack solenoid, the solenoid causes the feed rock shaft driving frame action lever fastened to the right endof driving
frame action shaft to rotate and push the feed rock shaft driving frame upward and hold it inthis position until back tacking
is completed. While the above takes place, the feed reverse lever remains immovable due to the slot provided on thejoint
portion of the feed reverse lever hinge stud crank connecting link which is connected to the feed rock shaft driving frame.
The feed rockshaft driving frame stopper lever provided on the feed reverse lever hinge studcrankhasbeen designed to control
the
reverse stitch length to same stitch length asset for forward stitchwiththe feed regulating dial on the feed reverse lever.
The automatic back tack switch connected to the control box permits automatic back tacking at start and at end of stitching
independently. The numberof stitchesin reverse iscontrolledby the control box.
Back tacking canbe done at any desired position during the sewing operation by depressing the pushbutton switch provided
adjacent to the needle bar. The machine will continue to sew in reverse while the push buttonis depressed, however, when the
machine is stopped, the protective circuit automatically cutsoff the current supply to the solenoid after 12 seconds even when
the push button is continuously depressed.
SETTING AND ADJUSTMENT OF BACK TACK DEVICE
Setting of Back Tack Solenoid (Fig. 36)
The back tack solenoid is correctly setinthe machine before the machine leaves the factory. If, however, this setting has been
disturbed and resetting becomes necessary, reset as instructed below.
Setting
Setthe back tack solenoid sothat there isa clearance of about 0.7mm (.03") between the flange ofits plunger andthe rotating
hook shaft when plunger is pushed toward the shaft.
When assembling the back tack solenoid linkto the solenoid, be sure the solenoid iscorrectly positioned laterally and correctly
angled sothatthe link can operate smoothly and without any binding inthe groove provided onthe plunger.
Adjustment
Loosen the two screws holding the back tack solenoid bracket and adjust position of solenoid as required and re-tighten the
screws.
18
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