How to Sharpen a Lawn Mower Blade

Sharpening your lawn mower’s blade is not a difficult process, but it does involve a number of steps and is important if you want to ensure good performance. That is why the experts at Ben Nelson Golf and Outdoor Equipment have created this guide to safely and efficiently sharpening your lawn mower’s blade.

Safely Remove the Blade

Before attempting to remove the blade, make sure that the lawn mower’s engine is off. If you want to be extra safe, remove the spark plug to ensure that there is no chance that the engine will start by accident. We also suggest marking the bottom of the blade with paint or a piece of tape to make it easier to remember which side is which. 

Your next step will be to tilt the lawn mower on its side with the carburetor facing up. Put a 2x4 between the blade and the lawn mower deck's skirt to help the blade resist the board when you take the bolt off. Unscrew the bolt using a breaker bar or a long-handle wrench.

Inspect the Condition of the Blade

Inspect the blade before you start sharpening. We recommend having a replacement blade on hand so that you can compare it to the current blade. If the current blade needs to be replaced, this will make swapping it out all the more easy. 

Your lawn mower’s blade should have a straight cutting edge and a thick trailing edge. The cutting edge should also be free of dents and chips. If your current blade exhibits any of these signs of wear and tear, it is time to replace it. 

Sharpen the Blade

Sharpening should be done with a file that is at least ten inches long. Begin your strokes at the top side of the cutting edge and push downwards with firm, smooth movements. Twenty to thirty strokes should be sufficient. Avoid oversharpening, as this can throw the blade off balance. 

Balance the Lawn Mower Blade

An unbalanced lawn mower blade is likely to vibrate and strain the blade's shaft. To balance the blade, put a nail in a board and use the blade's bolt hole to set it on the nail. If the blade tips to a certain side, file that side down until things are even. You should only file the blade down a little at a time, so the process can take some time. Be patient, go slowly, and keep checking until things are balanced out. 

We here at Ben Nelson Golf and Outdoor Equipment hope you found this information to be helpful. To view our selection of lawn mowers, visit one of our three locations. You can find us in Madison, Mississippi and Biloxi, Mississippi, as well as in Memphis, Tennessee. We are proud to serve communities like Hattiesburg, Mississippi.