MTD 580 Series Operator's Manual page 15

SECTION 11: MAINTENANCE
WARNING:
ground the
performing any repairs or maintenance.
NOTE:
When tipping the unit, empty the fuel tank
and keep engine spark plug side up.
TROUBLE SHOOTING
Refer to page 18 of this manual for trouble shooting
information.
CUTTING BLADE
When removing the cutting blade for sharpening or
replacement, protect hands by using heavy gloves
or a rag to grasp the cutting blade.
1. Remove the bolt and bell washer which hold the
blade-pulley assembly to the engine crankshaft.
Remove the assembly from the crankshaft.
2. Remove the two bolts and lock nuts from the
assembly and remove the blade from the blade
adaptor and pulley.
WARNING:
Periodically
blade adapter and pulley for cracks,
especially if you strike a foreign object.
Replace when necessary.
When sharpening the blade, follow the original angle
of grind as a guide. It is extremely important that
each cutting edge receives an equal amount of grind-
ing to prevent an unbalanced blade. An unbalanced
blade will cause excessive vibration when rotating at
high speeds, may cause damage to the mower and
could break, causing personal injury.
The blade can be tested by balancing it on a round
shaft screwdriver. Remove metal from the heavy side
until it balances evenly. It is recommended that the
blade always be removed from the adapter for the
best test of balance.
Before reassembling the blade-pulley assembly to
the unit, lubricate the engine crankshaft and the inner
surface of the blade adapter with light oil (or engine
oil). Lubricating the bolt holes, bolts and inner sur-
face of the nuts is also recommended.
Installing the blade
1. Install the pulley over the blade adapter with the
"star" away from the pulley. Refer to Figure 17.
Be sure to disconnect and
spark plug wire before
inspect
2. Place the blade on the adapter with the side of
he blade marked bottom (or with part number)
facing away from the adapter.
3. Secure the blade to the assembly with two hex
bolts and lock nuts. Tighten the hex bolts to the
torque listed in the "Blade Mounting Torque"
Section below.
4. Install the blade assembly up on the crankshaft.
Secure with the hex bolt and bell washer
(cupped side of washer to blade) and tighten to
torque listed in the "Blade Mounting Torque"
section below.
Locknut
Blade
Adapter
the
Hex Bolt
Washer
Blade Mounting Torque
Blade Adapter Bolts:120 in. lbs. min., 150 in. lbs. max.
Center Bolt: 450 in. lbs. min., 600 in. lbs. max.
To ensure safe operation of your unit, all nuts and
bolts must be checked periodically for correct
tightness.
DECK
The underside of the mower deck should be
cleaned after each use to prevent a buildup of grass
clippings, leaves, dirt or other matter. If this debris is
allowed to accumulate, it will invite rust and
corrosion, and may cause an uneven discharge of
grass clippings at the next cutting.
The deck may be cleaned by tilting the mower and
scraping clean with a suitable tool (make certain the
spark plug wire is disconnected).
15
Pulley
Assembly
Locknut
Blade
Hex Bolt
Bell Hex Bolt
Figure 17