Cub Cadet 439 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 rotating at high
speeds. It may cause dam
-
age to mower, and could
break causing personal
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, Figure 5-2.
3. Remove blade and adapter from the crankshaft,
Figure 5-2.
4. 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 the blade,
follow the original angle of grind. Grind each cutting
edge equally to keep the blade balanced.
5. 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.
6. 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 the ground when the mower is in the operating
position. Make sure that the blade is aligned and
seated on the 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.
Replacing Rear Flap
1. To remove rear flap, cut off the flat end of the wire rod
which secures it to the deck, Figure 5-3.
2. Attach the new flap and new rod to deck, bending the
ends of the new rod over to secure to deck.
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.
Do not use a pressure washer or garden hose to
clean your unit.
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 5-2: Remove the bolt, support, and adapter to access
the blade.
Figure 5-3: Cut wire to remove rear flap.