DeWalt DW12A-O1T9739 Instruction Manual page 17

PRODUCT CARE, cont'd
3. Turn mower on its side keeping the muffler side
down and making sure that the air filter and the
carburetor are facing up.
4. Remove bolt (a) and blade bell support (b) which
hold the blade and the blade adapter to the engine
crankshaft
(Figure 16).
5. Remove blade (c) and blade adapter (d) from the
crankshaft
(Figure 16).
6. Remove blade from the blade adapter for testing
balance.
a. Balance the blade on a round shaft screwdriver
to check.
b. Remove metal from the heavy side until it
balances evenly.
NOTE: When sharpening the blade, follow the original
angle of grind. Grind each cutting edge equally to
keep the blade balanced.
WARNING: An unbalanced blade will cause
excessive vibration when rotating at high
speeds. It may cause damage to engine and
blade could break causing personal injury.
7. Lubricate the engine crankshaft and the inner
surface of the blade adapter with light oil (Figure
16 inset).
a. Slide the blade adapter (d) onto the engine
crankshaft.
b. Place the blade on the adapter such that the side
of the blade marked "Grass Side" (or with part
number) faces the ground when the mower is in
the operating position.
c. Make sure that the blade is aligned and seated on
the blade adapter flanges.
8. Place blade bell support (b) on the blade (c). Align
notches on the blade bell support with small holes
in blade.
9. Replace hex bolt (a) and tighten hex bolt to
torque: Min. 37.5 ft-lbs (50.8 N-m), Max. 50.0 ft-lbs
(67.8 N-m).
NOTE: To ensure safe operation of your mower,
periodically check the blade bolt for correct torque.
Belt Care
A damaged or worn belt may prevent the mower from
self-propelling. Periodically inspect the belt and pulley
system for damage or wear. If necessary contact an
authorized Service Center to have belt replaced.
NOTE: Several components must be removed in order
to change the mower's drive belt. See an authorized
Service Center to have belt replaced.
17
d
b
a
Figure 16
c