Although this has recently been refurbished and now sports four fine sails, there is still an issue with the cap rotation. This is currently being fixed.
Today there has been a man on a hoist undercoating the cap - rather him than me! This photo was taken from our front garden. The man is visible more clearly if you click to enlarge the photo. He is painting the cap. Imagine doing this on the end of a rope, this far off the ground, and managing not to spill a drop of paint!
See http://www.burwellmuseum.org.uk/ .