Gravely 991091 ZT HD60 Owner's/Operator's Manual page 23

Sharpen the Mower Blades
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.
• Air lifts become eroded.
• Blade is bent or broken.
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 the
mower blade.
3. Check mower blade balance.
Slide mower blade on an unthreaded
bolt. A balanced blade should remain in
a horizontal position. If either end of
mower blade moves downward, sharpen
the heavy end until blade is balanced.
4. Install mower blade(s) on unit.
5. Tighten the bolts to a torque of 115 –
160 lbf-ft (156 – 217 N•m).
DO NOT Sharpen to This Pattern
2
4
DISCARD if more than
1/2 in. (1.27 cm)
3
4
Sharpen to this pattern
1. Cutting Edge
2. Square
Corner
Figure 10
1
1
OT0792
3. Air Lift
Erosion
4. Air Lift
GB - 23
BATTERY
WARNING: AVOID INJURY.
Read and understand entire
Safety section before proceeding.
WARNING: Battery posts,
terminals and related accessories
contain lead and lead
compounds, chemicals known to
the State of California to cause
cancer and reproductive harm.
Wash hands after handling.
Unit comes equipped with a maintenance-
free battery that requires no regular
maintenance except cleaning the terminals.
Remove Battery
1. Shut OFF engine. Engage parking
brake. Remove the ignition key.
2. Place seat in the service position (See
Maintenance Schedule on page 19).
3. Disconnect cables from battery
(negative, then positive) (Figure 11).
4. Remove hold down and remove battery.
Replace Battery
1. Replace battery and secure with battery
hold down.
2. Reconnect cables to battery (positive,
then negative). Position boot over
positive terminal.
3. Return seat to operating position.
Clean Battery
Keep battery and its terminals clean. Inspect
every 100 operating hours or monthly for best
performance.