You don't need any fancy special tools, a long flat head screwdriver and a large crescent wrench is all. Use the screwdriver in the bolts in the pulley behind the fan to hold it in place. Then, you should have enough leverage with the large crescent wrench to turn it. If not you can hit the wrench with a hammer until it comes loose. You may need someone else to hold the screwdriver when you hit it. Ya Da