- 1). Wait to change your blades until after you have mowed and come close to draining your gas tank of fuel. Turn off the fuel valve and pull the spark plug wire to ensure the mower won't start during the blade-replacement process. Put on work gloves to protect your hands from cuts while handling the blades.
- 2). Flip your mower over on its right side, being sure that the carburetor faces up to avoid any fuel leakage. Position a wooden block between the blade you're removing and the mower deck assembly to prevent the blade from turning as you loosen it.
- 3). Use a 14-mm socket wrench to remove the blade bolts and washers, which you should set aside. Slide off the blades from the blade holder. Replace those blades with sharpened blades that you have purchased from your mower's manufacturer.
- 4). Reinstall the washers and blade bolts. Use a torque wrench to tighten the blade bolts to a torque of between 36 and 43 foot lbs. Flip the mower upright. Turn on the fuel valve and reconnect the spark plug wire.
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