I could manage a slight wiggle from the machine, but that was it. Even with the clutch engaged, the main wheel kept going without moving anything. I couldn’t see any lint (anywhere - which made me wonder if it had actually been used) or any obvious jams. It did have a heavy grease or motor oil on all the parts that should move. It had hardened to a horrible wax like substance which I suspect did more harm than good.
So I took it apart the wheel to see if the clutch was working. Aside from more wax/grease, it seemed to be fine. I couldn’t turn the shaft, so I decided to put it back together and try something else.
Next, I spray WD40 on all the gucked up parts. Don’t worry, I rinsed it out with sewing machine oil afterwards. Still no luck getting it to move, but now there is the sound of metal on metal. Hmm…
I followed my ears, and found that it was coming from the bobbin area.
… and found the problem.
Such a small bit of thread and yet it prevented the machine from working. I suppose this means that the machine must have been used at some point in the past.
I reassembled everything, oiled with sewing machine oil, and ran the machine. Listening for anywhere it is running rough, applied more oil, ran the machine some more.
Now it runs very smoothly. I just have to make some thread guides (the only parts missing) before I can try sewing on it. I won't know 100% if it works until then, but fingers crossed.