Homelite UT13126 User Manual - Page 14

MAINTENANCE  Place the new blade on the shaft against the fan assembly. Make sure it is installed with the curved ends pointing up toward the mower deck and not down toward the ground.  Replace the blade insulator and spacer, then thread the blade nut on the shaft and finger tighten. NOTE: Make certain all parts are replaced in the exact order in which they were removed.  Torque the blade nut down using a torque wrench (not provided) to ensure the bolt is properly tightened. The recommended torque for the blade nut is 450600 in. lbs. SHARPENING THE BLADE See Figure 14. For best mowing performance, the mower blade must be kept sharp. A dull blade does not cut grass evenly and overloads the motor. Under normal circumstances, sharpening the blade twice during the mowing season is usually sufficient. However, if your lawn has sandy soil, more frequent sharpenings may be required.  Following the instructions in the Replacing the Cutting Blade section, remove the mower blade. DO NOT attempt to sharpen the blade while it is attached to the mower. WARNING: When removing, inspect the blade carefully. If blade is bent or damaged, replace immediately with a new blade. Failure to replace a bent or damaged blade could cause an accident resulting in possible serious injury. � Using a fine-tooth file or stone, sharpen cutting edges on both ends of the blade, removing equal amounts of material from both ends. BALANCING THE BLADE See Figure 15. When sharpening, care should be taken to keep the blade balanced. An unbalanced blade will cause excessive vibration when the mower is running. This vibration will eventually cause damage to the mower, especially the motor. To check the blade balance:  Clamp a screwdriver horizontally in a vise as shown. NOTE: If a vise is not available, a straight nail can also be used.  Place the center hole of blade on the screwdriver (or nail) shank.  If blade is balanced, it will remain in a horizontal position. If either end of the blade drops downward, sharpen the heavy side until the blade is balanced. FAN ASSEMBLY SHAFT BLADE SPACER BLADE INSULATOR BLADE NUT Fig. 13 Fig. 14 Fig. 15 Page 14