How to Change A Lawn Mower Blade

Although it fortunately doesn’t happen too often in the course of owning a mower, the blades in your machine, just like your lawn, need a little love. Sometimes, you’ll be able to get away with just having to sharpen them, but when the time comes for replacing, we’ve put together a quick rundown of how to change a lawn mower blade.

How to Change a Lawn Mower Blade: Getting Started

First things first, make sure you’re looking after yourself before looking after your mower. In order to avoid accidents and injuries, make sure you’ve removed all the gas from the tank, either by emptying it, or letting the mower run until it it’s out of fuel. Generally, if you’ve recently cut your lawn without refilling the tank, there shouldn’t be a whole lot left to empty or burn.

If you’re working with a corded mower, just make sure it’s unplugged, and go ahead and unplug the spark plug, too. Keep your hands on by ensuring nothing can turn on.

It should also be noted that if you did just finish mowing or letting the fuel burn out, to give your mower enough time to cool down. This shouldn’t take more than an hour.

Now that you’re working with a cooled and safe mower, you’re ready to turn it on its side. It definitely helps to be changing your blades on a flat surface, and in some cases, you may need to have something heavy enough to help support your mower’s weight.

Once everything’s in position, we recommend taking note of how each blade is positioned, so it’s easier to properly put everything back together. A simple enough way to do this is just snapping a quick pic with your phone. Then, use a socket wrench to loosen and remove the mounting bolts that are holding the blades in place, followed by the blade itself.

If you have the manual to your mower, it should have the model and size of the mower blades you’ll need, and you can pick them up from the hardware store before beginning this whole process, but if you’d rather be absolutely sure, you can always take a just-removed blade with you to the store and match it correctly to the type you need. It could also be that this is where you find out your blades just needs a sharpening more than they need to be tagged out.

In any case, once you have your new blades (or re-sharpened blades), you can refer to the photo you took of the original positioning, and remount your blades accordingly, followed by installing the and tightening the bolts as needed.

Before returning your mower to its normal position, carefully spin the blades to make sure nothing is wobbly, loose, or spinning off a normal axis.

Now that everything has been changed and checked, set your mower back down to its regular position and refuel it (unless it’s a corded mower). Give the gas about one hour to work its way through the engine before turning it on so no harm comes to your mower.

And just like that, it’s ready, set, cut.