White 671 - Troubleshooting Machine Operation

CHECK-UP
FOR
SMOOTH SEWING
MACI4INE
WORKlN
EAVlLY
If the machine
works hard after
standing idle for some
time, apply a little
kero
sene in place
of
oil. Then run the
machine rapidly to
clean
the
bearings,
and
oil with
sewing machine oil.
The use of inferior oil
is usually
the
cause of
the
machine working
heavily.
THREAD BREAKS
If the
needle thread
breaks,
it is probably due to one of the
following
causes:
The
machine being
improperly
threaded.
The
tensions being too
tight.
The
needle being
bent or having
a blunt point.
The
thread being too coarse for
the size of
the needle.
(see
page 23)
The thread
take-up
spring broken.
If the
lower thread breaks,
adjust the bobbin
tension
(Fig. 18)
also
see that
the
inside of
the bobbin case
and
the
underneath
part of
the tension
spring
are
free
from lint.
21