Honda HRA21 Owner's Manual page 28

BLADE REMOVAL AND SHARPENING
* Wear heavy gloves CO protect your hands.
Before tilting the mower, remove the spark plug
cap.
1. Tilt the mower so the carburetor side is up.
Loosen the blade bolts to remove the blade.
* Never tilt the mower so the carburetor side is down.
It will result in hard starting.
2. Sharpen the blade cutting edges with a file. File
the top side only. Maintain the original bevel for a
fine cutting edge. File both ends evenly to main-
tain blade balance.
NOTE:
Use only a genuine HONDA replacement blade or
equivalent.
3. Clean away any dirt and grass from around the
blade shaft.
4. Install the blade so that the blade bolts are securely
tightened with specified torque.
Torque: 4.5 - 5.5 kg m (32.5 - 39.8 ft lb)
IJP
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