You most likely found the answer but if anyone else is interested and if you were talking about the mandrels on the mower deck you will need an impact wrench and compressor to remove the pulley from the mandrel. The best way to do it is with the mandrel still in the mower deck and the blade still on it. Have it facing down to the ground (normal position) and use the impact driver with the correct size socket (in reverse of course)and remove the nut. If the pulley is stubborn you can tap it with a rubber mallet or a dead blow hammer to loosen it. If that doesn't work you need to get a wheel puller/remover kit from your local auto parts store. Then remove the mandrel form the deck. Good luck!