Gravely Promaster 992066, 992067, 992068, 992069, 992070, 992071, 992072 Owner's/Operator's Manual page 18

2. Put seat in service position.
3. Remove any dirt that may be around the
cap/dipstick on the hydraulic reservoir.
4. Remove cap/dipstick.
5. Check hydraulic oil level mark on cap/dipstick.
6. Add 15W50 Synthetic oil as needed. Do not overfill.
Change Hydraulic Fluid and Filter
Change the hydraulic oil filter and hydraulic oil every 500
hours. Use Mobil 15W50 synthetic oil for best component
life.
1. Clean around dipstick cap and dipstick. Remove
dipstick.
2. Place container under oil filter to catch oil.
3. Remove oil filter.
4. Allow tank to drain.
5. Lubricate rubber gasket on new oil filter with clean
hydraulic oil.
6. Spin new oil filter onto filter housing until it makes
contact. Tighten oil filter another 1/2 turn.
7. Add new oil to the oil tank. It will take about 4
quarts. Use Mobil 15W50 synthetic oil for best
pump and wheel motor life.
8. Properly dispose of waste oil.
MOWER BLADES
Remove
CAUTION: Use sturdy gloves or padding to
protect hands when working with mower
blades.
1. Turn the engine off. Remove the ignition key.
Remove the ignition wire from the spark plugs.
2. Remove the bolts, lock washer, flat washers, and
blades from the spindle shafts.
Replace
1. Put the blades, flat washers, lock washers, and the
bolts back on the spindle shafts.
2. Tighten the bolts to a torque of 115-120 lbf-ft
(156-162.6 N•m).
3. Replace the ignition wire on the spark plugs.
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 115-120 lbf-ft
(156-162.6 N•m).
DO NOT Sharpen to This Pattern
2
DISCARD if More
Than 1/2 in. (1.27 cm)
3
4
Sharpen to This Pattern
1. Cutting Edge
2. Square Corner
GB - 18
1
4
1
3. Air Lift Erosion
4. Air Lift
Figure 8
OT0792