Removing And Installing The Mowing Blade; Sharpening The Mowing Blade; Storage And Periods Of Inoperation (Winter Break) - Viking MB 448 TX Instruction Manual

– if the measured values are achieved at
one or more points or are outside the
permissible limits.
If the multi-blade available as a special
accessory is installed on the lawn mower,
different wear limits apply (see instruction
manual for accessory).
12.5 Removing and installing the
mowing blade
Removing:
● Use a suitable wooden block (1) to
counterhold mowing blade (2).
● Unscrew the blade fastening screw (3).
Remove the mowing blade (2), blade
fastening screw (3) and retaining
washer (4).
Installation:
Risk of injury!
The mowing blade (2) must only be
installed as shown. The tabs (7)
must face downwards and the
curved wings must point upwards.
Observe the specified torque when
tightening the blade fastening
screw, as the secure attachment of
the cutting tool depends on this.
Additionally secure the blade
fastening screw (3) with
Loctite 243.
Replace the spring washer (4) each
time the blade is installed and the
blade fastening screw (3) each time
the blade is replaced.
● Clean the blade contact surface and
blade bushing.
0478 111 9823 E - EN
● Install the mowing blade (2) with the
curved wings pointing upwards
(towards the machine). The locating
lugs (5) on the blade bushing must be
located in the bores (6) of the mowing
blade.
● Use a suitable wooden block (1) to
counterhold mowing blade (2).
● Install the blade fastening screw (3)
with a new retaining washer (4) and
tighten.
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Tightening torque: 60 - 65 Nm

12.6 Sharpening the mowing blade

VIKING recommends having the mowing
blade sharpened by a technician.
Operation of the machine is impaired in the
case of an incorrectly sharpened blade
(incorrect sharpening angle, imbalance
etc.).
Sharpening instructions:
● Remove mowing blade (
● Cool the mowing blade when
sharpening, e.g. with water. The blade
must not be allowed to display blue
colouring, as this would reduce its
cutting quality.
● Sharpen the blade evenly to prevent
vibrations due to imbalance.
● Observe sharpening angle of 30°.
● After sharpening, remove any
sharpening burr at the cutting edge
using fine sandpaper if necessary.
● Observe the wear limits. (
12.7 Storage and periods of
inoperation (winter break)
Store the machine in a dry, locked, dust-
free place. Make sure that it is out of the
reach of children.
Any faults must be remedied prior to
storage. The machine must always be in a
safe operating condition.
Empty the fuel tank and carburettor prior to
storage (e.g. by running empty).
Also note the following points when storing
the machine for long periods (winter
break):
● Clean all external parts of the machine
with care.
● Thoroughly lubricate/grease all moving
parts.
● Unscrew the spark plug (see engine
instruction manual) and pour approx.
3 cm³ of engine oil into the engine via
the spark plug hole. Turn the engine
12.5).
several times with the spark plug
removed (pull the recoil starter rope).
Fire hazard!
Keep the spark plug socket away
from the spark plug hole due to the
danger of ignition.
● Screw the spark plug back in (see
engine instruction manual).
● Perform an oil change (see engine
instruction manual).
● Cover the engine and store the
machine in the normal position.
12.4)
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