A productive evening
My Adler Contessa de Luxe now works! It has a lovely font. I cleaned it, changed (respooled) the ribbon, and made a few little adjustments. It still has two problems: one of the sticky keys is still sticky (the others aren't anymore), and the bell doesn't work most of the time. But I'm happy, it's the first machine I actually repaired.
I don't know, at least not yet. I've only been doing this for two years, maybe they didn't have time to gunk up.
I use the oil I buy to lubricate sewing machines. Not only I oil everything that is metal against metal, I rub some of it on every spot it I consider it needs protection from rust.
I stopped worrying about too much oil when I read on a typewriter repair course from I don't know what decade that after drying in an oven to put it in an oil bath to lubricate and protect metal surfaces. I won't go to those extremes but made me realise that if I put too much oil worst thing it could happen is that the typewriter will need a new cleaning next year.
Thanks. I agree with the "worst thing" comment. I can always clean the machine again!