This is true of most sewing machines of that era. I had a Montgomery Ward machine that sat in a closet for about 30 years, took it out, threaded it, put a bobbin in it and started sewing. it was a wonderful machine.
Unfortunately, I truly abused it and broke it but good. I didn't mean to abuse it - I did what i did out of ignorance. Lesson learned.
Be careful of thrift store buys unless they are very low dollar priced. Sometimes they simply don't work. Other times, all the machine needs is a good cleaning and a bit of oil. The thing is, you can't tell until you try to sew with it. If the machine costs almost nothing and you are somewhat handy, then spend the money. You can usually find manuals on line, so that's not usually a problem.