Lockstitch sewing machine

[AlZilla]

I apparently also have too much time on my hands because I went and looked at the linked diagram, specifically page 7 and 8 (the list of part names), I see that the cable is obviously connected to the lifting mechanism but I don't understand why.

Look at the full diagram, there's a handle on the back of the machine (part #22) that appears to operate the release mechanism directly and a couple of rods (parts 5 & 13) that appear to connect directly to the knee lifter from the release mechanism.

I also notice that the mystery cable doesn't have a number, part number or name associated with it. And it doesn't show the lower end of the cable connected to anything.

Very odd.

(EDIT) I think we have the shoe on the wrong foot. Maybe operating the lift/release mechanism causes that cable to perform some other function.

Edited April 1, 2023 by AlZilla

[AlZilla]

OK, how about this ... does the machine have an automatic thread trimmer and it's activated by the cable when the presser foot is lifted?

[AlamoJoe2002]

Can you replace the cable with an inexpensive bicycle cable...crimp down both ends..

[Wyowally]

Interesting data and manual if indeed that's the OP's machine. IF it is, the manual says that thread tension will be released when the thread trimmer does it's thing. The cable is related to that trimmer, and is part #36 in the listing, calling it a "thread tension release wire". IF it is the machine, the wire doesn't come into use until the trimmer is used then. Now if I could just learn to sew.