MTD 838 Lawn Mower User Manual


 
11
5
Maintaining
Your Lawn
Mower
An unbalanced blade
will cause excessive
vibration when rotat-
ing at high speeds. It
may cause damage
to mower, and could
break causing per-
sonal injury.
When removing
the cutting blade
for sharpening or
replacement or
when sliding the belt
around it, protect
your hands with a
pair of heavy gloves
or use a heavy rag to
hold the blade.
WARNING
Blade Care
WARNING: When removing cutting
blade for sharpening or replacement,
protect your hands with a pair of heavy
gloves or use a heavy rag to hold blade.
1. Disconnect spark plug wire from spark plug. Turn
mower on its side making sure that the air filter and
the carburetor are up.
2. Remove bolt, blade bell support, blade, and blade
adapter from the engine crankshaft, Figure 5-3.
NOTE: When removing the blade, blade adapter, etc., be
careful not to remove or lose parts above it associated
with the engine pulley.
3. The blade can be sharpened with a file or on a grind-
ing wheel. Do not attempt to sharpen the blade while
it is still on the mower. When sharpening blade, follow
original angle of grind. Grind cutting edges equally to
keep blade balanced.
4. Remove blade from the adapter for testing balance.
Balance the blade on a round shaft screwdriver to
check. Remove metal from the heavy side until it
balances evenly.
WARNING: An unbalanced blade
will cause excessive vibration when
rotating at high speeds. It may cause
damage to mower, and could break
causing personal injury.
5. Lubricate the engine crankshaft and the inner surface
of the blade adapter with light oil. Slide the blade
adapter onto the engine crankshaft. Place the blade
on the adapter such that the side of the blade marked
“Bottom” (or with part number) faces the ground when
the mower is in the operating position. Make sure that
blade is aligned and seated on blade adapter flanges.
6. Place blade bell support on the blade. Align notches
on the blade bell support with small holes in blade.
Replace hex bolt and tighten hex bolt to torque: 450
in. lbs. min., 600 in. lbs. max.
To ensure safe operation of your mower, periodically
check the blade bolt for correct torque.
Belt Care
1. Disconnect the spark plug wire and ground it against
the engine.
2. Drain the fuel tank or place a piece of plastic beneath
the cap to prevent gasoline leakage.
3. Tip mower on its side (air cleaner side of engine up).
4. Remove blade, adapter, and related hardware as
instructed under “Blade Care” above.
5. Loosen self-tapping screw that secures deck baffle to
the deck, Figure 5-4.
Figure 5-3: Remove bolt, bell support, blade, and adapter to
gain access to the blade.
Figure 5-4: Loosen the screw that holds deck baffle onto deck.
Figure 5-5: Remove belt from transmission and engine pulley.