Thanks for the info, Nancy. I like the fact that it states the year of manufacture on the bottom--wish all companies did/had done that.
Regarding the cleaning of the motor before you used it ... it's a precautionary measure--not that you did any damage. As DT (DesertTortoise) discovered--although his is an extreme case--there might be some nasty stuff inside your motor, the brushes may need replacing, the fans may have metal fatigue, et cetera. Another thing I would do is take the cleaner outside, install the hose into the blower port, and ensure that there is nothing lodged inside; dropping a golf ball through it is another way to check for clogs. To check for a hose's air-tightness attach it to the blower port, mist a diluted dish soap solution around the outside of it, turn the machine on, and cover the open end of the hose with the palm of your hand. Bubbles will form around any leaks. In that case, you can seal the leaks with liquid rubber such as Plasti Dip (search the archives using the keywords: "Plasti Dip" or "Woven Hose Repair" to learn the procedure).
Yes, your machine is definitely a vintage treasure. Enjoy!