It would be a good idea to gently work the focus cam back and forth over its whole travel fifty times or so to ensure that the oil works in properly. What you are doing here is rejuvenating the old lube which has gone all crusty by dissolving it in the new oil. That is an acceptable technique unless the old lube has picked up a lot of grit.
Congratulations on your Leningrad. This is in my opinion the very best of FSU cameras, well made, and with features found nowhere else. Parallax-correcting moving framelines in a finder good for 35, 50, 85, and 135mm lenses, and a genuine, clear, split image rangefinder instead of the coincident image RF found in all screwmount Leicas, Canons, Nikons, and other FSU cameras. Leitz only got the clue for this kind of RF with the M series. It is a pity it never found its way into another FSU camera.
And of course its major trick is the spring winder, which is noisy but effective. The wind spring is also very strong, so I would suggest that repeatedly firing it with no film in it would probably be a bad idea.
It is certainly a unique-looking camera, and will inspire comment when you carry it around!
Cheers,
Dez
