Move the deck adjustment lever to the bottom notch on the rear fender. This lowers the deck to give more room to work on the mower's pulley system.
Remove the sheet metal screws that hold all the belt guards onto the mower deck. With the screws removed, place the guards off to the side.
Place yourself in front of the lawn tractor and find the pulley connected to the driveshaft at the bottom of the engine. Remove the belt guard that mounts over the pulley with a socket and ratchet.
Pull the old belt off the pulley on the front of the lawn tractor. Find the pulley mounted to the spring-loaded bracket on the mower deck. Push the pulley away from the belt and slip the belt over the pulley. Remove the belt from the pulleys on the deck.
Place the new belt onto the pulleys and pull the belt forward so you can install it onto the front pulley extending from the engine. Push the idler pulley away from the belt, slip the belt over the pulley and let go of the pulley to create tension on the belt.
Place the belt guard over the front pulley and secure it with the bolts and socket.
Place the belt guards onto the mower deck and secure them with the sheet metal screws and screwdriver.