Bobbin in white featherweight won't stay in
 

I am new to the featherweight world, as I recently purchased a lovely machine that was operating with a nice stitch. I ordered a new belt, thoroughly cleaned it, oiled it, put the new belt on. Now the bobbin won't stay in. The thread comes up to the top and the wheel turns freely. I have studied the diagrams regarding reassembly of the bobbin case, and everything looks right. The bobbin doesn't seem to "click" when I put it in. Does anyone have any ideas? If I try to sew, the needle goes up and down and then the bobbin falls out.

Is the finger in the bobbin assembly in the notch? There's a notch under the feed dog plate that the finger needs to be in to work correctly. Is it threaded from right to left?

Yes to both.

Are you sure you wound a correct bobbin? An incorrect bobbin will not fit right in the case and would do what you're describing.

If you are sure the finger is in the right place, then how much oil did you use? More than one drop will cause issues with the bobbin. Take a q-tip and wipe it out. If that doesn't help, get a different bobbin.

When u are putting the bobbin in do not hold the latch open, or it wont snap.

It is the same bobbin and thread that I used when I got it. I have purchased some new bobbins, maybe I will wind one of those and see. I was very careful w the oil, actually I was worried that I didn't use enough, but I will double check that also. I'll be back! Thanks.

Ok, so I changed the bobbin , it still did it. But then I was showing my DH how the bobbin (case) didn't click to stay in, and it did!! It has a perfect stitch, sounds great. I did clean some additional grime out of the cracks of the bobbin case,....maybe that did the trick. I hope it doesn't reoccur, but all is well now. Thanks so much for all your suggestions.

Glad you got it worked out. Gunk can always be the culprit:>

You may want to take a good look at the bobbin case. It may have gunk, like Candace mentioned, or old oil, or it may be missing a screw or spring. (I'm guessing without seeing a pic. :) ) I have a blog article here:
http://www.archaicarcane.com/2013/03/spring-has-sprung/ that may help. It shows how to take the whole thing apart and clean it up and reassemble. Just be careful, there are a few small parts, and they jump.