MTD 80 Lawn Mower User Manual


 
11
5
Maintaining
Your Lawn
Mower
WARNING
When removing
the cutting blade
for sharpening or
replacement, protect
your hands with a
pair of heavy gloves
or use a heavy rag to
hold the blade.
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.
Blade Care
WARNING: When removing the cutting
blade for sharpening or replacement,
protect your hands with a pair of heavy
gloves or use a heavy rag to hold the blade.
Periodically inspect the blade adapter for cracks,
especially if you strike a foreign object. Replace when
necessary. Follow the steps below for blade service.
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 the bolt and the blade bell support which
hold the blade and the blade adapter to the engine
crankshaft. See Figure 4.
3. Remove blade and adapter from the crankshaft.
4. The blade can be sharpened with a file or on a
grinding wheel. Follow the original angle and grind
each cutting edge equally. Do not attempt to sharpen
the blade while it is still on the mower.
5. Place the blade on a round shaft screwdriver to check
for balance. 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.
6. To reassemble, lubricate the engine crankshaft and
the inner surface of the blade adapter with light oil.
Slide the blade adapter onto the engine crankshaft.
7. Place the blade on the adapter such that the side
of the blade marked “Bottom” (or with part number)
faces ground when the mower is in the operating
position. Make sure that the blade is aligned and
seated on blade adapter flanges.
8. Place blade bell support on the blade. Align notches
on the blade bell support with small holes in blade.
9. 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.
Off-Season Storage
The following steps should be taken to prepare your lawn
mower for storage.
Clean and lubricate mower thoroughly as described in
the lubrication instructions.
Refer to engine manual for correct engine storage
instructions.
Coat mower’s cutting blade with chassis grease to
prevent rusting.
Store mower in a dry, clean area. Do not store next to
corrosive materials, such as fertilizer.
When storing any type of power equipment in a poorly
ventilated or metal storage shed, care should be taken to
rust-proof the equipment. Using a light oil or silicone, coat
the equipment, especially cables and all moving parts of
your lawn mower before storage.
Figure 4
Hex Bolt
Blade
Bell
Support
Blade
Blade Adapter
Crankshaft