How to Adjust a Walk Behind Mower That Pulls
- 1). Remove the screws that secure the belt drive cover onto the top front of the mower deck, then lift the cover off the deck to expose the drive belt and transmission. In some cases, you must squeeze the sides of the cover before it will pop off the deck.
- 2). Locate the tensioner setscrew on the transmission next to the pulley mounted on the end of the transmission.
- 3). Turn the setscrew clockwise to increase tension on the belt. Do not over-tighten the belt as it can cause undo tension in the transmission and decrease performance.
- 4). Place the cover onto the mower deck and secure it with the screws and screwdriver.
- 5). Test the mower. If the belt still slips when you engage the transmission, remove the cover and tighten the belt further. Repeat this until the mower propels smoothly without belt slippage.
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