I was guessing the 60's but that's crazy if it's from the 30's ! Thank you for the link. Turns out it was half empty..filled up and spent about 1/2 hour bleeding. Works perfectly and doesn't leak. Although I think there is a screw missing on fill plug / vent. Anyway there had to be a floor jack...
Was given this jack. Goes up slowly and definitely feels like air is in system oil appears to be low and leaks. But she still lifts a 32gvwr dump truck...so can't complain ! Question, too add fluid and purge air. Just fill in large port on cylinder while lowered then raise and with plug...