Removing And Installing Mowing; Sharpening Mowing Blade - Viking MA 339 Manual De Instrucciones

If the supplied standard blade is not
installed in the lawn mower, but e.g. the
mulching blade, which is available as a
special accessory, different wear limits
apply (see instruction manual Kit 339).
Risk of injury:
A worn or damaged blade may
break off and cause serious
injuries. The instructions for blade
maintenance must therefore always
be observed.
In particular, the lawn mower must
not be operated if parts of the
cutting unit (comprising the mowing
blade, blade fastening screw and
blade mounting) are damaged or
worn.
Blades are subjected to differing
degrees of wear depending on the
location and duration of use. If you
use the mower on sandy ground or
use it frequently under dry
conditions, the blade will be
subjected to greater loads and will
wear more quickly than the
average.
Always replace the blade fastening
screw (4) when replacing the
mowing blade.
13.7 Removing and installing
mowing blade
In order to prevent damage to the
blade fastening screw, use a
suitable hexagon socket (22 mm)
for loosening and tightening.
1 Removing:
● Use a suitable wooden block (1) to
counterhold mowing blade (2).
0478 131 9917 G - EN
● Unscrew blade fastening screw (3) and
remove mowing blade (2).
2 Installing:
Risk of injury:
The mowing blade (2) must only be
installed as shown. The tabs (6)
must face downwards and the
curved wings must point upwards.
Observe the specified torque of
10 - 15 Nm when tightening the
blade fastening screws, as the
secure attachment of the cutting
tool depends on this. Additionally
secure the blade fastening
screw (3) with Loctite 243.
● Clean blade contact surface and blade
bushing.
● Install mowing blade (2) with curved
wings pointing upwards. Locating
lugs (4) must be located in bores (5) of
mowing blade.
● Use a suitable wooden block (1) to
counterhold mowing blade (2).
● Tighten blade fastening screw (3) to a
torque of 10 - 15 Nm.

13.8 Sharpening mowing blade

Risk of injury:
Check blade for damage before
installing. The blade must be
25
replaced if notches or cracks are
identified, if the blade is worn back
by 5 mm, or if the blade is thinner
than 1.6 mm at any point (
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.
13.9 Storage (winter break)
Storing the lawn mower:
Remove the safety plug and
remove the battery.
Keep the safety plug separately from the
lawn mower and out of reach of
unauthorised persons, particularly
children.
Store the lawn mower in a dry locked place
that is generally free of dust. Ensure that it
is protected from unauthorised use
(e.g. by children).
Only store the lawn mower in good
operating condition, fold down the
handlebar if necessary.
13.6).
Keep all nuts, pins and screws tightly
fastened, replace danger signs and
warnings on the machine that have
become illegible, check the entire machine
for wear and damage. Replace all worn or
damaged parts.
13.7).
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