Singer class 251 - Needle Thread Take-Up Spring Adjustment; Presser Bar Height Setting

From the library of Superior Sewing Machine & Supply LLC - www.supsew.com
36
TO REMOVE NEEDLE
BAR
LINK
AND
THREAD TAKE-UP
Remove
needle
bar
link
and
thread
take-up
in
the
following
manner:-
1.
Remove
face
plate
and
arm
hole
plug
A3,
Fig.
50
from
ma-
chine.
DO NOT
DISTURB
Z2
Y2
2.
Remove
needle
bar,
upper
needle
bar
bushing,
presser
bar
and
guide
bracket
T,
Fig.
51
as
instructed
on
page
35.
3. Loosen
set
screw
Y2,
Fig.
50
in
needle
bar
crank,
reaching
with
a
screwdriver
through
the
hole
in
the
arm,
opened
by
re-
moval
of
plug
A3,
and
turning
DO NOT
DISTURB
U2
machine
pulley
as
required.
Fig.
so.
Needle
Bar
Crank
4.
Using
wrench
146057
(through
same
hole)
and
turning
machine
pulley
as
required,
loosen
the
large
hexagon
head
clamping
screw
Z2, Fig.
50,
on
the
needle
bar
crank.
CAUTION:
DO
NOT
DISTURB the smaller
hexagon
head
position screw
U2, Fig.
50,
which
holds
the
needle
bar
crank
at
its
correct
position
on
the
horizontal
arm
shaft.
•;
~~3
G3
03
F3
W 4
~
J3
Fig. 5
I.
Needle
Bar
Link
and
Thread
Take-up
H3
t
.5.
Loosen
small
set
screw
B3, Fig.
51
in
the
rear
of
the
arm
of
the
machine.
6.
Insert
a
face
plate
screw
E3,
Fig.
51
in
the
tapped
hole
in
center
of
stud
C3, Fig.
51
and,
while
holding
back
the
needle
bar
link
inside
the
head
at
G3,
Fig.
51,
pull
upon
the
screw
E3
until
the
stud
C3
is
removed.
Remove
face
plate
screw
from
stud.
7. Back
ti1e
end
of
the
take-up
H3,
Fin.
51
toward
the
inside
of
the
machine
turning
the
ma-
chine
pulley,
as
required
until
the
takr>-up
is
free
of
the
slot
provided
for
it.
8. The
needle
bar
link
G3
and
take-up
HJ
con
now
be
pulled
free
of
the
needle
bar
crank
WITHOUT
DISTURBING
THE
NEEDLE BEAR-
INGS F3, Fig.
50.
..
37
NOTE:
If
the
needle
bearings
F3, Fig.
50,
are
accidentally
disturbed,
they
must
be
re-assembled
so
that
there
are
exactly
18
bearings
in
each
of
the
two
assemblies.
TO
REPLACE
THE
NEEDLE BAR LINK
AND
THREAD TAKE-UP
Replace
the
needle
bar
link
and
thread
take-up
in
the
following
manner:-
1.
Make
sure
that
the
wearing
plate
J3
is in
place
on
the
face
of
the
needle
bar
crank,
as
shown
in Fig.
51.
Place
the
needle
bar
link
G3
and
take-up
H3
in
the
head
of
the
machine
so
that
the
stud
in
the
center
of
the
linkage
slips
into
the
hole
provided
for
it in
the
needle
bar
crank,
as
shown
in
Figs.
50
and
51.
2.
Slip
the
upper
end
of
the
take-up
H3
through
the
slot
provided
for
it in
the
head
of
the
machine.
3.
Insert
stud
C3
through
needle
bar
link
G3
and
into
its
hole
in
the
machine
casting
so
that
the
flat
on the stud faces the
rear
of
the
machine.
The
mark
03
on
the
stud
indicates
the
position
of
this
flat.
Fig.
51
shows
the
stud
with
the
mark
D3
in
the
correct
position
.
4.
When
the
stud
C3
is
fully
and
correctly
inserted,
turn
the
set
screw
B3
inward
lightly
against
the
flat
on
the
stud
C3.
5.
Insert
a
screwdriver
through
the
hole
in
the
front
of
the
head
of
the
machine
and
turn
machine
pulley
as
required
to
reach
set
screw
Y2
in
needle
bar
crank.
While
tightening
screw
Y2,
turn
stud
W4
by
hand
to
find
its
flat,
then
slightly tighten
set
screw
Y2
in
needle
bar
crank.
Make
certain
that
assembly
F3
is
firmly
against
wearing
plate
J3.
Produce
a
very
slight
side
play
by
pushing
take-up
lever
H3
gently
right
and
left;
then
securely
tighten
screw
B3.
6.
Using
wrench
146057
through
same
hole
and
turning
machine
pulley
as
required,
tighten
hexagon
head
screw
Z2.
7.
Securely tighten
set
screw
Y2.
8.
Replace
guide
bracket
T in
head
of
machine,
as
shown
in
Fig.
51.
9.
Replace
and
adjust
presser
bar,
upper
needle
bar
bushing
and
needle
bar
with
their
accessories,
as
instructed
on
pages
19
and
35.
10.
Replace
and
securely
tighten
arm
hole
plug
A3.
11.
Replace
the
face
plate
(see
instructions
at
bottom
of
page
19).