ok first you have to remove the crank assembly.
now you're going to have to use 6ft of hard wire (music wire works well) and fish the wire thru the joint pulley where the pole bends. (if your umbrella bends)
Now use another piece of wire about 12" long with a small hook on one end to catch the longer wire once you see it at the top pulley.
bend a hook on the 6ft wire tape new rope or a piece of thread and attach it to the new rope and pull it thru.
the rest should be easy. Good luck! Unc
Uncle Steve, July 2009