Yes that thing should spin freely
Scott,
That unit absolutely needs to spin freely or do not try to roll up your sail. Just hoist the sale in the luff groove each time until you can get a solution that works. Climbing a mast at sea to fix a jammed halyard is not a lot of fun unless you like being the weight on a pendulum 40 feet in the air.
I am concerned by your comment about your standing rigging that sounds jury rigged and your desire to climb your mast. Having worked in manufacturing facilities my entire life I have seen far too many accidents that were completely avoidable, some of which caused loss of life. One of these was a fall from ten feet where the person hit their head on the floor. Make sure if you are going aloft that you have a proper harness, bosuns chair, etc. made for the purpose. I always use a second line as a safety line, just in case. Plan it with the idea that you can not make a mistake and no second chances. If someone is hoisting you also be aware that you could drop a tool on their head, a hard hat or motorcycle helmit is a good idea, or once you are aloft and tied off get them out of the drop zone. I would not want to get hit with a screwdriver dropping from 40 feet. Not knowing what your rigging looks like I can't comment on the suitability to support you, only you can decide how much risk you are willing to take.