Originally Posted by Rodney

There are links to Muv's videos in the sticky on cleaning old machines. Take some time and read the sticky and watch the videos. They will take a lot of the mystery out of cleaning these old machines. After that, clean all the dust, dirt and lint that you can find out then oil the snot out of it with either sewing machine oil or tri-flow. Don't be tempted to use other products. Put oil in every hole you see on the body of the machine. Remove the nose plate and open the bobbin cover. Oil everything inside that looks like it should move. Now do the hard part. Walk away for a day or two. After a good long wait go back and see if anything starts moving. It didn't seize up overnight, it may take some time for the oil to work it's magic and get things freed up again.
201s are true rotary machines. There will be a couple sets of gears on the underside that will need grease. A light synthetic grease like Tri-flow grease is a good choice or use Singer grease if you can find some. Download an owner's manual from Singerco.com. There should be lubrication instructions inside.
Good luck with it. You'll have one of Singer's best machines when you're done.
Rodney