Murray 201012X83E Operator's Manual page 20

LAWN MOWER
Always observe safety rules when perform-
ing any maintenance.
TIRES
• Keep tires free of gasoline, oil, or insect
control chemicals which can harm rubber.
• Avoid stumps, stones, deep ruts, sharp
objects and other hazards that may
cause tire damage.
BLADE CARE
For best results, mower blade must be kept
sharp. Replace a bent or damaged blade.
A CAUTION: Use only a replacement blade
approved by the manufacturer of your mower.
Using a blade not approved by the manu-
facturer of your mower is hazardous, could
damage your mower and void your warranty.
TO REMOVE BLADE
• Disconnect spark plug wire from spark
plug and place wire where it cannot
come in contact with plug.
• Turn lawn mower on its side. Make sure
air filter and carburetor are up.
• Use a wood block between blade and
mower housing to prevent blade from
turning when removing blade bolt.
NOTE: Protect your hands with gloves
and/or wrap blade with heavy cloth.
• Remove blade bolt by turning counter-
clockwise.
• Remove blade and attaching hardware
(bolt, lock washer, hardened washer).
NOTE: Remove the blade adapter and
check the key inside hub of blade adapter.
The key must be in good condition to work
properly. Replace adapter if damaged.
TO REPLACE BLADE
• Turn lawn mower on it's side. See engine
manual for proper direction of turning
over the engine.
• Use a wood block between blade and
mower housing to prevent blade from
turning when removing blade bolt.
• Protect your hands with gloves and/or
wrap blade with heavy cloth.
• Remove blade bolt, Iockwasher, flatwasher.
• Remove blade and blade adapter.
• Inspect the key inside blade adapter.
Replace adapter if damaged.
IMPORTANT: Blade bolt is Grade 8 heat
treated.
• Install new or sharpened blade with
trailing edge up toward the engine.
• Position blade on blade adapter. Align
the two (2) holes in blade with raised
lugs of adapter.
• Reassemble blade bolt, lock washer
and flat washer into blade adapter and
crankshaft in exact order as shown.
• Position block of wood between blade
and mower housing.
• Tighten blade bolt securely. Recom-
mended tightening torque is 35-40 ft. Ibs.
IMPORTANT: Blade bolt is heat treated.
If bolt needs replacing, replace only with
approved bolt shown in the Repair Parts
section of this manual.
Blade adapter Key
Lockwasher
de
bolt Hardened
washer
J \
Trailing edge
Crankshaft
Crankshaft
TO SHARPEN BLADE
NOTE: We do not recommend sharpening
the blade - but if you do, be sure the blade
is balanced. An unbalanced blade will
cause excessive vibration and eventual
damage to lawn mower and engine.
• The blade can be sharpened with a file
or on a grinding wheel. Do not attempt
to sharpen while on the mower.
• To check blade balance, drive a nail into
a beam or wall. Leave about one inch of
the straight nail exposed. Place center
hole of blade over the head of the nail. If
blade is balanced, it should remain in a
horizontal position. If either end of the
blade moves downward, sharpen the
heavy end until the blade is balanced.
GRASS CATCHER (IF SO EQUIPPED)
Grass catcher may be hosed with water
but must be dry when used.
_,CAUTION: Under normal usage, the
catcher material is subject to deterioration
and wear and should therefore be checked
to ensure compliance with original
manufacturer specifications.
ENGINE
Read the maintenance section of your
engine manual.
LUBRICATION
Change the oil after the first two hours of oper-
ation and every 25 hours thereafter or at least
once a year if the lawn mower is not used for
25 hours in one year. Refer to engine manual.
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