Singer 628 - Needle-Thread Tension Assembly; Removal and Disassembly; Reassembly and Replacement; Adjustments

NEEDLE-THREAD TENSION ASSEMBLY
STUD CHECK SPRING
RELEASING PIN
SET SCREW
THREAD GUARD
Removal and Disassembly
Open face plate, loosen stud set-screw and re¬
move entire tension assembly, as illustrated. Loosen
set screw in dial and remove dial. Turn adaptor to
left until it is free from the stud. Remove indicator
stop, spring, cup, and tension releasing-pin. The
check spring, tension discs, and thread guard should
be removea from ‘he stud as a unit.
Reassemoiv and Rsoiacement
Replace releasing-pm in stud. Place tension
discs on the thread guard, align coil of check spring
with holes in tension discs and thread guard, and
place assembly on stud with tail of check spring
entering top groove of sprocket on stud. Replace cup,
spring, indicator stop (with tab at bottom position),
and adaptor. Replace dial, making certain that stop
on inside of dial is in contact with left side of in¬
dicator-stop tab when dial is set at zero (0) tension.
Tiahten set screw and place entire assembly onto
machine, with check spring resting on the top sur¬
face of the check-spring stop.
Adjustments
For adjustments of the needle-thread tension,
check-spring stroke, check-spring tension, and bob-
bin-case latch tension, refer to pages 21 and 22 in
the Service Manual for C!asses600 and 603 Machines.
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