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Ryobi RY40109 20" Mower Blade Replacement

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    1. Ryobi RY40109 20" Mower Blade Replacement, Blade: step 1, image 1 of 3 Ryobi RY40109 20" Mower Blade Replacement, Blade: step 1, image 2 of 3 Ryobi RY40109 20" Mower Blade Replacement, Blade: step 1, image 3 of 3
      • Before working with the blade, remove the battery.

      • Firmly grasp the battery, depressing the battery release and slide the battery out.

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    2. Ryobi RY40109 20" Mower Blade Replacement: step 2, image 1 of 1
      • Turn the mower upside down on a flat, stable surface.

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    3. Ryobi RY40109 20" Mower Blade Replacement: step 3, image 1 of 2 Ryobi RY40109 20" Mower Blade Replacement: step 3, image 2 of 2
      • Preventing the blade from spinning is an important safety step!

      • Use an 8" to 10" block of 2x4 to prevent the blade from spinning counterclockwise.

      • You may have to experiment a bit to position it correctly.

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    4. Ryobi RY40109 20" Mower Blade Replacement: step 4, image 1 of 1
      • Protect your hands by putting on your heavy-duty canvas gloves while working around the blade.

      • Using a 15 mm socket wrench, remove the blade nut by turning it counterclockwise.

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    5. Ryobi RY40109 20" Mower Blade Replacement: step 5, image 1 of 3 Ryobi RY40109 20" Mower Blade Replacement: step 5, image 2 of 3 Ryobi RY40109 20" Mower Blade Replacement: step 5, image 3 of 3
      • Remove the nut spacer and blade insulator.

      • Remove the blade.

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    6. Ryobi RY40109 20" Mower Blade Replacement: step 6, image 1 of 3 Ryobi RY40109 20" Mower Blade Replacement: step 6, image 2 of 3 Ryobi RY40109 20" Mower Blade Replacement: step 6, image 3 of 3
      • Identify the alignment shapes on the blade hub.

      • Install the new blade on the hub using the alignment posts.

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    7. Ryobi RY40109 20" Mower Blade Replacement: step 7, image 1 of 3 Ryobi RY40109 20" Mower Blade Replacement: step 7, image 2 of 3 Ryobi RY40109 20" Mower Blade Replacement: step 7, image 3 of 3
      • Replace the insulator, spacer, and nut.

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    8. Ryobi RY40109 20" Mower Blade Replacement: step 8, image 1 of 1
      • Re-block the blade to keep it from spinning clockwise this time.

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      • Set the torque wrench to between 310-360 in.lbs.

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    9. Ryobi RY40109 20" Mower Blade Replacement: step 10, image 1 of 1
      • Tighten the blade nut with the torque wrench by rotating the wrench clockwise.

      • You have completed the replacement! Time to mow the grass!

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Finish Line

Cancel: I did not complete this guide.

Jim Keplinger

Member since: 09/25/24

181 Reputation

1 Guide authored

Team

CSU Sacramento, Team 1-8, Laflen Fall 2024 Member of CSU Sacramento, Team 1-8, Laflen Fall 2024

CSUSAC-LAFLEN-F24S1G8

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