HOW TO REPLACE LAWN MOWER BLADES: DO’S AND DON’TS

The quality of your lawn mower’s blades has a huge effect on not only how it cuts but also the health of your lawn. As you mow, you may hit a rock or branch that damages the blade so badly that you must change it. Here’s a quick look at how to replace lawn mower blades yourself and save a few bucks.

Gear Up

Before you begin, there are a number of items you’ll need to gather, including: • A replacement lawn mower blade for your mower’s make and model • Adjustable or socket wrench (to remove bolt holding the blade on) • Shop towels

Safety First

Over time, your mower’s blade will become chipped from hitting rocks, branches and other debris. When a blade is severely damaged, it will need to be replaced entirely. Start by removing the spark plug to prevent an accident start-up, then turn the mower on its side. To prevent fuel from leaking out, be sure to turn it so the carburetor is on top.

Before you start to take the blade off, always wrap the sharp ends of the blade in shop towels to protect yourself from injury. Removing the blade is as simple as holding it steady and loosening the anchoring nut. We recommend using a block of wood wedged against mower deck and the blade to prevent the blade from turning.

Out With the Old

Grab a wire brush and clean up the head of the nut or bolt holding the blade. Next use an adjustable or socket wrench to loosen the bolt in the center. For stubborn bolts a cordless impact can make quick work of the job. Before removing the blade, use a permanent marker note which direction the sharpened side is facing. Once you have the bolt off, slide the blade and retaining bracket off the shaft. Now is a great time to give your mower deck a good cleaning if you have time.

Mount the New Blade

With the new blade wrapped in your shop towel, place the blade on the shaft, followed by the retaining bracket, and reinstall and tighten the bolt. Although most mower blades are designed so they can only be installed with the correct side facing down, make sure the sharp side of the blades is facing the same way as your old blade. With the mower back on its wheels, start the engine to make sure there’s no vibration and that the mower is cutting properly. Vibration will indicate an issue with your installation, such as a loose bolt or crooked blade.

Changing the blade on your mower is a quick and easy process. Performing this maintenance yourself rewards you with the satisfaction of a job well done. With a couple shop towels and a wrench, you can get your damaged blade swapped out in no time.

Check out all the lawn & garden products available on NAPA Online or trust one of our 16,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on how to replace lawn mower blades, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.