How to Repair a Lawn Mower Pully
- 1). Park the lawn mower on a level surface. Wash the mower deck with fresh water to clean any grass cuttings and dirt from the deck before servicing.
- 2). Place two or three 4 by 4 blocks under the mower deck to prevent the blades from spinning while removing the pulley nut. With blocks in place, lower the mower deck to the lowest setting. Ensure the wooden blocks rest between the mower blades, and not underneath them.
- 3). Remove the pulley nut with a ratchet and socket of the proper size. With the nut removed, use a hammer to slightly tap upward on the pulley at opposite sides. The pulley will loosen, and then release from the shaft.
- 4). Inspect the key stock on the shaft for damage or wear. If either defect is apparent, replace the key stock by removing it with a small pry bar or pliers. Install the new key stock of the same size into the key way.
- 5). Lightly grease the shaft and install the new pulley. Line the pulley up with the key stock and lightly tap pulley into place with a hammer. Use care not to damage the pulley by hitting it too hard while installing.
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