How to Remove and Replace a Push Lawn Mower Blade

Spring is here, which means it’s time to start mowing your lawn!  Before you get started, it’s worth taking a moment to replace your push lawn mower blade. Typically, blades wear out every 1-2 years and must be replaced to achieve the best possible cut.

To get an immaculate lawn, our experts at AppliancePartsPros.com have put together this ultimate guide to removing and replacing a lawn mower blade. In 15 minutes or less, you’ll have a new blade installed for a clean, even cut that’s the envy of the entire neighborhood.

Need a lawn mower blade replacement? Shop for all the lawn mower parts you need on AppliancePartsPros.com.

Need a new lawn mower blade? Search below using your specific model number to identify the exact part needed:

When it’s time to replace your lawn mower blade

When in doubt, replace your lawn mower blade. They only cost about $15-$35 a pop and it’s worth getting a nice cut for your lawn all season long while you save money.

Some red flags that you should replace your blade ASAP include:

• The cut is unclean and/or uneven.
• The blade vibrates excessively while mowing.
• The blade is in poor condition (bent, scratched, rusted, etc.).
• The blade is 2+ years old.

If one or more of these statements is true, you should definitely remove and replace your lawn mower blade this spring.

How to buy the correct replacement lawn mower blade

To start, buy the replacement blade that you need. How do you know what blade to get for your mower? Check for key information about your mower blade in the operator’s manual. Specifically, you should look for:

• The OEM number: This is the number of the blade assigned by the manufacturer. You can use this number to easily find the right blade.

• Model name and number: If you can’t find the OEM number, use the model name and number to get the appropriate blade.

• Length and center hole design: Without the OEM number or model, you can use the blade length (measured diagonally) and center hole design (circle size, rounded rectangle, H-pattern, Y-pattern, or 5-point, 6-point or 7-point star) to get a product that will work with your lawn mower.

For example, you can type in any of this information below into our search engine at Appliance Parts Pros.com to see if your lawn mower blade is available for purchase. Two of our most popular blades include the Husqvarna Walk-Behind Lawnmower Blade and the Husqvarna 4-in-1 Blade.

Once you purchase the right blade for your mower, have it handy to install.

What you’ll need to replace a lawn mower blade

Time: 15 minutes or less

Parts

• New lawn mower blade

Tools

• Wrench or ratchet
• Vice grips, C-clamp or block of wood
• 2 Ziplock bags
• Work gloves

How to remove and replace a lawn mower blade

1. Check your operator’s manual for any model specifics

Before you replace a lawn mower blade, take a look at your operator’s manual for any specifics you should know about your model. The instructions for replacing a blade will vary depending on the mower model, so don’t skip this step.

2. Remove the spark plug wire

Make sure the lawn mower won’t start up while you maintenance it. After all, manually turning the sharpened blade is the same motion the machine makes to power up.  Most mowers are gas-run, so you’ll need to remove the spark plug wire for safety. You can find this towards the front of the mower. It looks like a little black boot. Put on your work gloves for protection and disconnect the spark plug wire. To ensure it doesn’t make contact and start up the mower, you can wrap a Ziplock bag around the plug. This will give you extra security.

3. Ensure no fuel leaks

Next, you’ll want to ensure your lawn mower doesn’t leak out fuel as you replace the blade. There are a few ways to do this. You could run down the gas before replacing the blade so this isn’t an issue.  Or you can simply remove the fuel tank cap, add a Ziplock bag over the opening and then screw the cap back on. This will stop fuel from leaking out as you maintenance the mower. For extra protection, add a mat under your mower to protect your driveway from leakage.

4. Tip the mower on the correct side

Now that the mower is secured, you should tip it on the correct side with the air filter facing up. This is often the same side that grass blows out of. For most mowers, this is the right side (as you stand behind the mower).  By tipping it on the right side, you’ll protect the air filter as you replace the lawn mower blade.

5. Lock the blade in place

You’ll need to lock the blade in place so that it doesn’t spin and you don’t cut yourself while removing it.  This can be easily done either by locking vice grips or a C-clamp to the side of the mower, so that the blade can’t turn when you loosen it. Or, if you prefer, simply wedge a block of wood in the mower undercarriage so that the blade can’t move.

6. Loosen the bolt and washer

Take a wrench or ratchet and start loosening the bolt that holds the blade in place. As a general rule of thumb, you should turn it left or counterclockwise to loosen it.  Once it’s loose enough, remove the bolt and the washer that retain the blade.

7. Make note of the blade’s right side up

Before you remove the lawn mower blade, make note of which side is positioned upwards. It’s easy to mix up the sides and replace the blade upside-down.

Pro tip: Take a photo of the blade before you remove it, so that you can compare if you get confused.

Now remove the blade and get ready to swap it.

8. Replace the blade in the correct position

Now pick up your new replacement lawn mower blade and position it according to the photo you took in the previous step. The blade center hole should line up and the wings should be facing the same way as the old blade.

9. Tighten the blade to the correct torque

Replace the washer and the bolt. Give the bolt a good twist by hand before picking up your wrench to finish tightening. If you have a torque wrench, even better. You can tighten the blade according to the operator’s manual. Either way, tighten the blade so it’s not at risk of spinning off anytime soon.

10. Restore your mower to its original state

Congratulations, you’ve successfully replaced your lawn mower blade! Now it’s time to put your lawn mower back to its original state:

• Tip your mower back to the upright position.
• Remove the Ziplock bag from the fuel tank and recap it.
• Remove the Ziplock bag from the spark plug and reattach it.
• Get mowin’! Your lawn mower is now ready to achieve a clean cut all season long.

Maintain your lawn mower on an annual basis

To keep your lawn mower in tip-top shape, you should keep up maintenance beyond replacing lawn mower blades. For example, some items you should perform every year include:

• Change the oil
• Clean the air filter
• Replace the spark plug
• Fog the engine
• Wash the lawn mower (especially the undercarriage)

As you maintain your lawn mower like a pro, you may need some lawn mower parts to finish the job. At Appliance Parts Pros.com, we’ve got a wide range of parts available so you can complete maintenance and get the sparkling lawn you’re looking for.

Lawn mower blade FAQs

How often should you replace your lawn mower blade?

As a general rule, you should swap your lawn mower blade every 1-2 years. For the best cut, it’s ideal to change it every season or when it develops a dull blade.

Which way do you turn the bolt to remove a lawn mower blade?

You should turn the bolt to the left or counterclockwise to remove a lawn mower blade. Remember to lock the blade in place with a vice grip, C-clamp or block of wood before attempting to loosen it.

Which side of the lawn mower blade is up?

Ideally you should make a note of the right side up when you remove the old blade. If you forgot to do this, here are a few clues to guide you:

• The manufacturer may have added a sticker or stamp indicating which side goes up.
• The cutting edge should face the grass blades, while the dull edge should face the mower.
• The wings or tapers should face up towards the underside of the mower.
• If the blade wobbles after you tighten it, you may have it upside-down.

Finally, once you have the blade the right side up, you might add a sticker of your own so that it’s easy for you to identify the right side in the future.

How do you remove a lawn mower blade that is stuck?

A lawn mower blade that’s stuck usually has an over-tightened bolt. To remove it, you’ll need extra leverage. You can use a ratchet or breaker bar to get more length as you try to loosen the bolt.

Should you sharpen your own lawn mower blade?

For most DIY repairmen, sharpening your own lawn mower blade isn’t worth it. Blades today come in complex shapes, with wings and inset cuts that can be difficult to sharpen. Unless you’re a professional with the right tools, it’s usually best to buy new blades.