Welcome. Neat machine. We like pictures. Instructions on how to post pictures on QB can be found at
https://www.quiltingboard.com/attach...020-01-17-.pdf
You will probably need to reduce or compress your pictures so that the file size is smaller than 1
.9MB.
I downloaded a manual for your machine from
https://www.singer.com/support and put in 764. There were some other machines in the results. I downloaded the W764. It looks like a classic 15 class hook shuttle and race cover. If I'm understanding correctly, you haven't been able to get it back together. I don't know if I can explain it very well, but will try.
Raise the needle bar to the highest position.
Take the post of hook shuttle in your left hand so the hooky, forky (of course, these aren't the technical terms, but most descriptive LOL) type end is at the bottom
Kind of twist post of hook shuttle so the aforementioned end goes around the race end (the crescent moon shaped part).
Once the hook shuttle is arranged around the race, you should be able to place the race cover over with the notch at the top (closest the needle plate).
Twist the clamps over the knobs on the race cover.
Load bobbin case with a bobbin as instructed in the manual.
Should you download the manual, the diagram shown on page 30 of the pdf is an exploded view of the assembly,
Janey - Neat people never make the exciting discoveries I do.
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