Maintenance Instructions
D21d
Checking and Servicing
76
CAUTION
ALWAYS wear eye protection and gloves
when sharpening a blade.
Wing
Tip
Do Not Grind or
Sharpen on Underside
Intersection
Wear Area
Sharpen at
Original 30° Angle
30°
Mower Blade Profile for Sharpening
6. Check blade balance by positioning the blade
horizontally
on a blade balancer or use a nail
or shaft through the center hole. If either end
of the blade rotates downward, grind (remove)
metal on that end until the blade will balance.
The blade is properly balanced when neither
end drops. Balance of a blade is generally
maintained by removing an equal amount of
material from each end of the blade when
sharpening.
Blade Balancer
Blade Balanced on Magnetic
Wall-Mounted Balancer
7. Mount the blade with wing tips pointing up into
the housing.
For gear-driven decks
reinstall
the blade, washer, lock washer, and nut.
Tighten the nut to 60 lb·ft (81 N·m).
For
belt-driven decks
reinstall the spacer (if ap-
plicable), blade, washer, and bolt.
Tighten
the bolt to 70 lb·ft (95 N·m).
NOTE:
When reinstalling blades on
GHS
models, remember, the blades counter-rotate
and the LH and RH blades must not be
switched. Check for proper blade rotation
before installing blades on the deck. Refer to
Blade Rotation
illustrations shown in
Clog-
ging Checklist on page 50
for correct blade
rotation.
Drive Belts
Raise the body and inspect the condition of the five
(5) belts (4 belts on SD models)
every 25 hours
of
operation—engine PTO drive, jackshaft drive,
hydrostatic ground drive, GHS blower drive, and
engine alternator belt. If the belts show
signs of
cracking or deteriorating,
the belts should be
replaced.
Refer to
Drive Belts on page 79.
Mower Deck Gearbox Oil Seals
The mower deck gearbox seals should be inspect-
ed
every 25 hours
for evidence of oil leaking;
particularly the lower oil seal on the blade drive
gearbox.
This seal is protected by the trash guard
on the blade hub and seal protector plate on the
housing, but is still vulnerable to seal damage due
to operating in an adverse environment. The mow-
er blade must be removed for inspection of the
seal, so it is recommended to
inspect the gear-
box seals when blades are removed for sharp-
ening.
If an oil leak is noted, the seal should be
replaced and the gearbox assembly relubricated.
Refer to
Mower Deck Gearbox Lubrication on page
62.
Fuel Lines and Clamps
Every year,
inspect the fuel supply line from the
tank to engine for deterioration or damage. Also,
inspect the fuel line
clamps for tightness.
Good
preventive maintenance calls for complete
replacement
of fuel lines and clamps
every two
(2) years.
NOTE:
This procedure is of special importance for
the diesel engine due to poor performance when
air is injected with the fuel.
