117.959. I have one. And I have that exact same cabinet, too, but it came with a different Kenmore.
The hand wheel on most rotaries moves away from the user because a friction drive means that the rotations of motor/wheel are opposite. The rubber on a friction pulley can be shaved with a very sharp knife. This is a temporary fix, though. This machine is equipped with a spring mounted motor that allows the pulley to rest apart from the wheel so that hard spots don't form on the tire. This is what causes the sound you describe.
These are good machines -- strong and simple to run. I bought mine for $3.99 including pedal, a box of feet and attachments, and the original manual. But I've seen them for over $100. This is not a boring machine at all; actually, it has quite a bit of character.