Other Riding mower & tractor Information
How to Sharpen a Lawn Mower Blade
It’s easy to tell when the blade on your lawn mower is dull: the tips of the grass blades are tattered and brown. You can sharpen the blade yourself, or take it to a hardware store to have it sharpened. To sharpen it yourself, safely, follow these steps:
- If you have a gas powered mower, disconnect the spark plug wire. Carefully tilt the lawn mower on its side with the fuel tank's fill hole facing up.
- Put on work gloves to protect your hands from being cut. To immobilize the blade, wedge a wood block between the blade and a solid area of the mower housing.
- Remove the bolt and washer, and inspect the bolt. If it’s damaged, replace it with one the manufacturer approves, rather than a standard bolt (you can order it from Sears PartsDirect). Blade bolts often are specially designed and heat-treated to prevent failure. Any failure of the blade assembly during use could throw a blade and cause a lot of damage.
- Remove and inspect the blade. If it’s bent, dented or badly chipped, get a manufacturer-approved replacement. A damaged blade cuts grass poorly and can make the mower vibrate excessively.
- Secure the blade in a vise and sharpen the blade with a file, or sharpen it on a bench grinder. Follow the existing angle of the cutting edge and, if using a file, file in only one direction.
- After sharpening, check that the blade is balanced. Drive a finish or casing nail into a wall and hang the blade horizontally, through the center hole. If one end dips, grind more from that end.
- Use a torque wrench to reattach the blade, tightening the bolt to the torque specified in the owner’s manual — most blade bolts require around 45 to 55 foot-pounds of torque.
- Reinstall the spark plug.