This is a Singer 221 Featherweight sewing machine that belonged to my Grandma. It was made sometime around September 1947.
The original motor was this "Catalog 3-100," rated for 100–110 volts. I ended up swapping it out for a new Alphasew motor.
The Featherweight motors that have lubrication holes should be greased with petroleum jelly (Vaseline), not oil or any other kind of grease. For $2.59 I bought enough to last several lifetimes. Here I've loaded it into a syringe for easy application:
The oil can clip holds on snugly to a bottle of Tri-Flow oil. Because the applicator straw is so easy to lose, I made a "holster" for it on the side of the bottle. First I put some yellow heat-shrink tubing around the entire straw so it would be easier to see and hold on to. Then I placed a short length of nylon guitar string inside a larger piece of red heat-shrink tubing and sealed it together at the bottom.
To put the straw away, I push the guitar string completely through the inside of the straw. This pushes out any remaining oil and keeps the whole thing held tight. Any remaining oil drips stay inside the red tubing.