Bolens 122-336-120 - Manual (Page 13)

1. Remove the large bolt and lock washer which
holds the blade and adapter to the engine
crankshaft.
2. Remove the blade and adapter from the
crankshaft. Be careful not to lose the key on
the crankshaft.
3. If the blade or blade adapter needs replacing,
remove the two small bolts, lock washers and
nuts which hold the blade to the adapter.
B. Sharpening
Remove the cutting blade by following the direc­
tions of the preceding section.
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 grinding to prevent an unbalanced blade. An un­
balanced 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 for balance by balancing
it on a round shaft screwdriver. Remove metal
from the heavy side until it balances evenly.
NOTE
It is recommended that the blade
always be removed from the adapter
for the best test of balance.
C. Reassembly
Before reassembling the blade and the blade
adapter to the unit, lubricate the engine
crankshaft and the inner surface of the blade
adapter with light oil. Lubricating the bolt holes,
bolts and inner surface of the nuts with light oil is
also recommended. A 4 oz. plastic bottle of light
oil
lubricant is available. Order part number
737-0170. Engine oil may also be used.
When replacing the blade, be sure to install the
blade with the side of the blade marked “Bottom”
(or with part number) facing the ground when the
mower is in the operating position. Make certain
key is in place on the crankshaft.
Blade Mounting Torque
3/8" Dia. Bolt 375 in. lb. min., 450 in. lb. max.
, 5/16" Dia. Bolt 150 in. lb. min., 250 in. lb. max.
To insure safe operation of your unit, ALL nuts
and bolts must be checked periodically for correct
tightness.
DECK
The underside of mower deck should be cleaned
after each period of use as grass clippings, leaves,
dirt and other matter will accumulate. This ac­
cumulation of grass clippings, etc., is undesirable
as 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 for­
ward or on its side and scraping clean with a
suitable tool or by washing with a stream of water
from a garden hose.
A
CAUTION
Do not direct the stream of water at
a hot engine as damage to the
engine may result.
ENGINE OIL
Check oil level before starting engine and after
every 5 hours of operation.
ADD oil as necessary to keep level to FULL to
point of overflowing.
Before removing oil fill plug, clean area around
plug to prevent dirt from entering oil fill hole.
Engine should be in a level position when check­
ing oil.
Change oil after first 5 hours of operation. There­
after change every 25 hours. Change oil while
engine is warm. Oil may be drained thru oil fill
hole by tipping the unit on its side. Oil capacity
1V4 pints.
AIR CLEANER
Service air cleaner every 25 hours under normal
conditions. Clean every few hours under extreme­
ly dusty conditions. Poor engine performance and
flooding
usually indicates that the air cleaner
should be serviced. See figure 23.
1. Remove screw.
2. Remove air cleaner carefully to prevent dirt
from entering carburetor.
3. Take air cleaner apart and clean.
a. WASH foam element in kerosene or a liq­
uid detergent and water to remove dirt.
b. DRY foam completely by wrapping and
squeezing in a cloth.
c. SOAK foam with engine oil. Squeeze to
distribute and remove excess oil.
4. Reassemble parts and fasten to carburetor.
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