I keep dragging home 401s - I've found them in all manner of derelict condition.
When you clean a 401 you don't want to soak it in a pan like you might one with out wiring. I take a can and put kerosene in it and just paint it on the moving parts. Someone on here suggested putting a disposable diaper down to catch the drips. Some times people used 3 in one oil on those machines - if so it will be pretty gummed up. Keep painting on the kerosene to dissolve the old oils. The stitch selector transmission clogs up and doesn't move if it has been over oiled. There is a piece that moves back and forth on the needle bar - and one near the cam stack - those can clog up with dead oil. Once you get it cleaned up use Tri-flow oil. There is a lot of info on the web site. If you want you can pm and I will answer???