Bolens 131-410A - Manual (Page 17)

MAINTENANCE
\
WARNING {
Disconnect spark plug wire and
ground it against the engine before
performing any repairs or mainte­
nance.
CUTTING BLADE
A. Removal for Sharpening or Replacement
WARNING
^
1 .
2 .
3.
Be sure to disconnect and ground
the spark plug wire before working
on the cutting blade to prevent
accidental engine starting.
Remove the large bolt and lock washer which
holds the blade and adapter to the blade spin­
dle. See figure 30.
Remove the blade and adapter from the spin­
dle. Be careful not to lose the key on the spin­
dle.
If the blade or blade adapter needs replacing,
remove the two small bolts, lock washers and
nuts which hold the blade to the adapter. See
figure 30.
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 and may cause
damage to the mower.
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.
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 blade spindle.
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.
C. Reassembly
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.
BELTS
Check that belts are free of oil or dirt. Wipe the
belts periodically with a clean rag.
NOTE
To insure safe operation, ALL nuts
and bolts must be checked periodi­
cally for correct tightness.
ENGINE OIL
Check oil level before starting engine and after
every 5 hours of operation or each period of use.
Refer to separate engine manual.
Change oil after first 5 hours of operation.
Thereafter change every 25 hours. Change oil
while engine is warm.
17