No it is not destined for the trash. There is a problem but it's not insurmountable. I've tried googling that Kenmore model and couldn't find any pics of the machine. I've got a number of 158 series Kenmores and find them to be a most acceptable group of machines.
Yours is sewing. So just take it slow and be patient. Work on it when you can, put it back on the shelf when the frustration gets to much.
I had one 15 clone that took me 2 years of working on it off and on to get it fixed right. I ended up buying another machine that was mechanically identical and using it to put the first one right. It sews just fine now.
In your other thread you have the top tension out, so check the release pin. Make sure it's free to move without any resistance. If it feels tight or binds then take the pin out and soak the tension in denatured alcohol and clean it good. Then continue with it.
Have you read the tension instructions in the TFSR manual? {
http://www.tfsr.org/publications/tec...machine_manual }? There is a lot of info in there.
Now, changing direction for a moment.
Remove the bobbin case. Put a full bobbin in it and thread it through the case tension. Hold the tension over your left hand by the string. If the case falls away the tension is too loose, tighten it a tiny bit at a time. If not, gently bounce the case. Does it drop away a little bit with each bounce? If not, the tension is too tight, loosen it a tiny bit after each test. The tension should be set so the case will drop away a bit with each bounce. I always set my bobbin tension this way first, then go on to the top tension.
Without having the machine in front of me, this is about all I can say. I hope it helps. Always feel free to ask questions. It's how we learn.
Joe