An important maintenance item that is often overlooked by homeowners is to periodically sharpen or replace the mower blades on their lawn tractors. Husqvarna recommends that this be done every 25 hours of mower operation for their tractors. Most homeowners only think about sharpening or replacing their blades after they have become dull and there is a noticeable decrease in cutting efficiency, which in turn causes increased wear and tear on the tractor. Blade replacement is easy on a Husqvarna, and you will be rewarded with a tractor that cuts much cleaner and faster.
Things You'll Need
SAE socket set
Flashlight (if needed)
Torque wrench (if available)
Replacement cutting blades (model specific)
Park the tractor on a flat, dry surface. Disconnect the spark plug wire from the plug to prevent the engine from accidentally starting while you are working around the cutting blades.
Raise the mower deck to the highest position by pulling the attachment lift lever all the way towards you. The lever is located on the right side of the tractor, between the steering wheel and the engine shroud. Turn the height adjustment knob on the dashboard clockwise to raise the mower deck to its full "up" position.
Put the tractor in low gear by pulling the transmission lever as far rearward as it will go. The lever is located on the right rear tire fender. Engage the parking brake by pushing it as far toward the ground as it will go.
Spread a drop cloth beneath the mower deck. Put on heavy work gloves and eye protection. Crawl under the tractor with a flashlight, a 5/8-inch SAE socket wrench and a clean rag.
Locate the three cutting blade attachment bolts, which are in the center of each cutting blade. Use the flashlight if necessary to find the bolts, which are likely covered with debris and caked-on grass; wipe them off with a clean rag.
Attach the 5/8-inch socket wrench to the nearest cutting blade attachment bolt and turn it counterclockwise. You may need to bang the wrench sharply with the heel of your hand to break the bolt free. Unscrew the bolt while maintaining a grip on the blade with your other hand. Remove the blade once the bolt comes free. Repeat this process for the other two blade attachment bolts and remove the blades.
Attach a new blade to the mandrel, which is the part to which the old blade was attached. Align the blade properly on the mandrel (it only fits one way), making sure that the "This Side Up" warning stamped on the blade's surface is facing away from the ground. Insert and tighten the 5/8-inch blade attachment bolt. If you have a torque wrench, torque the bolt to 45 to 55 foot pounds.
Repeat the blade attachment process for the other two blades. Tighten each bolt to 45 to 55 pounds of torque. Return the tractor to operating condition by following the reverse order of the blade-removal steps.
Eye protection will keep grass clippings and other debris out of your eyes while you work under the mower deck.
Keep a grip on the mower blade when the bolt is removed to prevent the blade from falling on you as you work.