Gravely Pro-walk hydro 36HR PG Owner's/Operator's Manual page 37

Replacing Mower Blades
1. Install the spacers (A), blades (B) and
bolts (C) on the spindle shafts.
2. Secure blades with a wooden block to
prevent blade rotation.
3. Tighten blade bolts to a torque of 120
lbf-ft (163 N•m).
4. Replace ignition wires on spark plugs.
Sharpen Blades
See Figure 38.
CAUTION: Avoid injury! Mower
blades are dangerous!
• Always wear gloves while
working on blades.
• Always wear safety eye
protection when grinding.
• Sharpen blades with grinder, hand file,
or electric blade sharpener.
• Keep original bevel (A) when grinding.
• Blade should have 1/64-in. (0.40 mm)
cutting edge (B) or less.
• Balance blades before installing.
Figure 38
NOTE: If mower is used under sandy soil
conditions, replace mower blades when air
lifts become eroded through at ends
(figure 39).
CAUTION: DO NOT sharpen
mower blades while on unit. An
unbalanced mower blade will
cause excessive vibration and
eventual damage to unit. Check
mower blade balance before
reinstalling blades.
NEVER weld or straighten bent
blades.
1. Remove mower blade from unit.
Discard mower blade if:
• More than 1/2 in. (1.27 cm) of metal is
removed. (Figure 39)
• Air lifts become eroded.
• Blade is bent or broken.
DO NOT Sharpen To This Pattern
DISCARD if more
than 1/2 in. (1.27 cm)
A
B
Balancing Blades
GB - 37
Sharpen To This Pattern
1. Air Lift Erosion Area
2. Cutting Edge
Figure 39
2. Sharpen mower blade by removing an
equal amount of material from each end
of mower blade. DO NOT change angle
of cutting edge or round the corner of
mower blade.
3. Check mower blade balance.
CAUTION: Avoid injury! Mower
blades are sharp. Always wear
gloves when handling mower
blades or working near blades.
1. Clean blade.
2. Put blade on nail or round pin in a vise.
Turn blade to horizontal position.
(Figure 40)
Figure 40
2
1