How to Repair the Pulley Belt on a Self-Propelled Lawn Mower
- 1). Disconnect the spark plug. Remove the two screws holding the cover of the mower deck in place. Push the two sides of the cover inward and pull up to remove it from the mower.
- 2). Loosen, but do not remove, the belt tension screw, which is located near the transmission. As you loosen the screw, the belt will sag. Tip the lawn mower onto its side.
- 3). Remove the bolt with a wrench, holding the cutting blade in place. Remove the cutting blade from the lawn mower.
- 4). Slip the belt off the engine pulley. Pull it out through the hole on the top of the mower deck.
- 5). Slip the new belt around the engine pulley on the bottom of the mower. Pull it to the front of the lawn mower and slip it over the transmission pulley.
- 6). Put the cutting blade back on the mower. Replace the bolt. Hold the blade in place and tighten the bolt with a wrench.
- 7). Flip the mower right side up. Tighten the belt tension screw until the belt is snug on the pulleys. Place the mower deck cover back on the lawn mower. Secure it with screws.
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