Craftsman Rotary Lawn Mower 917.379120 Owner's Manual page 11

LAWN MOWER
Always observe safety rules when per-
form ing any main te nance.
TIRES
• Keep tires free of gasoline, oil, or insect
control chemi cals which can harm rubber.
• Avoid stumps, stones, deep ruts, sharp
objects and other hazards that may
cause tire damage.
DRIVE WHEELS
Check front drive wheels each time be fore
you mow to be sure they move freely.
The wheels not turning freely means
trash, grass cuttings, etc. are in the drive
wheel area and must be cleaned to free
drive wheels.
If necessary to clean the drive wheels, be
sure to clean both front wheels.
1. Remove hubcaps, locknuts & washers.
2. Remove wheels from wheel ad just ers.
3. Remove any trash or grass cuttings
from inside the dust cover, pinion and/
or drive wheel gear teeth.
4. Put wheels back in place.
NOTE: If after cleaning, the drive wheels
do not turn freely, contact a Sears or other
qualifi ed service center.
BLADE CARE
For best results, mower blade must be
kept sharp. Re place a bent or dam aged
blade.
TO REMOVE BLADE
1. Disconnect spark plug wire from spark
plug and place wire where it cannot
come in contact with plug.
2. Turn lawn mower on its side. Make
sure air fi lter and carburetor are up.
3. Use a wood block between blade and
mower hous ing to prevent blade from
turning when re mov ing blade bolt.
NOTE: Protect your hands with gloves
and/or wrap blade with heavy cloth.
4. Remove blade bolt by turning counter-
clockwise.
5. Remove blade and attaching hard ware
(bolt, lock wash er & hardened wash er).
NOTE: Remove the blade adapter and
check the key inside hub of blade adapter.
The key must be in good con di tion to work
properly. Replace adapter if damaged.
TO REPLACE BLADE
1. Position the blade adapter on the en-
gine crank shaft. Be sure key in adapter
and crankshaft keyway are aligned.
2. Position blade on the blade adapter
aligning the two (2) holes in the blade
with the raised lugs on the adapter.
3. Be sure the trailing edge of blade (oppo-
site sharp edge) is up toward engine.
4. Install the blade bolt with the lock
washer and hardened washer into
blade adapter and crankshaft.
5. Use block of wood between blade and
lawn mower housing and tighten the
blade bolt, turning clockwise.
• The recommended tightening torque is
35-40 ft. lbs.
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
Blade
Blade
bolt
Hardened
washer Trailing edge
TO SHARPEN BLADE
NOTE: We do not recommend sharp en ing
blade - but if you do, be sure blade is balanced.
Care should be taken to keep the blade bal-
anced. An un bal anced blade will cause even-
tual damage to lawn mower or engine.
• The blade can be sharp ened with a fi le
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 ex posed. 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 purchased as an accessory)
• The grass catcher may be hosed with
water, but must be dry when used.
• Check your grass catcher often for dam-
age or de te ri o ra tion. Through normal
use it will wear. If catcher needs replac-
ing, replace only with ap proved replace-
ment catcher shown in the Repair Parts
section of this manual. Give the lawn
mower model number when ordering.
11
Crankshaft
keyway
Crank
shaft
Blade adapter