Bolens TMO-33920A - Manual (Page 19)

AIR CLEANER
Under normal operating conditions, the air cleaner,
located on top of the carburetor, must be serviced after
every ten hours of use. Under extremely dusty
operating conditions, the air cleaner must be serviced
after every hour of operation. To service the air cleaner,
refer to the separate engine manual packed with your
unit.
CLEANING ENGINE AND BLADE HOUSING
Any fuel or oil spilled on the machine should be wiped
off promptly. Grass, leaves, and other dirt must not be
left to accumulate around the cooling fins of the engine
or on any part of the machine.
Clean the underside of the blade housing after each
mowing.
SPARK PLUG
The spark plug should be cleaned and the gap reset
once a season. Spark plug replacement is recommend­
ed at the start of each mowing season; check engine
manual for correct plug type and gap specification.
CUTTING BLADE
A. Removal for Sharpening or Replacement
AC
WARNING
1
.
2
.
3.
Be sure to disconnect and ground
the spark plug wire and remove
ignition key before working on the
cutting blade to prevent accidental
engine starting. Protect hands by using
heavy gloves or a rag to grasp the
cutting blades.
Remove the large bolt and lock washer which holds
the blade and adapter to the blade spindle.
Remove the blade and adapter from the spindle.
Be careful not to lose the key on the spindle.
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 directions
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 unbalanced 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 spindle 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.
FUEL FILTER
Your unit is equipped with a replaceable in-line fuel
filter.
Replace filter whenever contamination or
discoloration is noticed. Order replacement filter
through your engine authorized service dealer.
DRIVE BELT REMOVAL AND REPLACEMENT
AC
WARNING
t
Disconnect the spark plug wire and
ground it against the engine. Block
the wheels of the unit.
NOTE
Figures 25 and 28 through 30 are shown
with the unit tipped up for clarity.
It is not necessary to tip the unit
to remove the belts.
However, if tipping the unit is desired,
remove the battery from the unit. To
prevent gasoline leakage, drain the
gasoline, or remove the fuel tank cap,
place a thin piece of plastic over the
neck of the fuel tank and screw on the
cap. Be certain to remove the plastic
when finished changing the belts. Block
unit securely.
19