I am perty good at fixing things. The lady next door ask me to look at her sister sewing machine. She said she took it to the sewing machine repair shop and they told her it was not worth the cost to fix it.
Well now it is a challenge. I cleaned everything oiled it and reassembled it. New needle (twice) new thread, bobbin, rethreaded many times.
It will sew a few stitches then skip a stitch then it might sew more then the thread would break. I would switch it to zig zag and the needle zig zaged but the stitch was straight. Does anyone have any experience with this machine or is it not worth fixing?

Are you sure the needle is in right? I think the needle goes in sideways, with the thread from left to right.

Looking at the book it says the flat side of the needle faceing away from you.

You could have thread and lint in the tension disks. Try to check this. Good Luck

The ZZ thing sounds like the tension is too tight. That'll cause the thread breaking, too. Check the book to see what direction the needle theads. I have three machines set up in my family room. The Elna threads front to back, the vintage Necchi threads left to right and the Singer 301 threads right to left. I need a back to front to complete the circuit.

Also check to see which direction the bobbin needs to spin.