Remove dirt from the cooling air guide
(inlet slots) between the motor cover and
the lower housing to ensure that the motor
is adequately cooled.
Clean the mowing blade.
Clean the underside of the mower with
water and a brush. Detach accumulated
cutting deposits in the housing and in the
ejection chute beforehand using a stick.
Never spray water onto motor
components, seals, bearing points or
electrical parts such as switches. This
would result in expensive repairs.
If you are unable to remove the dirt with
water using a brush or a cloth, VIKING
recommends the use of a special cleaner
(e.g. STIHL special cleaner).
12.3 Electric motor and wheels
The electric motor is maintenance-free.
The wheel bearings are maintenance-free.
12.4 Upper handlebar ME 339
Maintenance interval:
Before each use
The upper handlebar is coated with a
insulating layer. Should this layer become
damaged, the upper handlebar must be
replaced.
12.5 Mowing blade maintenance
Maintenance interval:
Before each use
● Tilt mower upwards into cleaning
position (
12.2).
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● Clean mowing blade (1) and check it for
damage (notches or cracks) and wear;
replace if necessary.
● Use a slide calliper (2) to measure
blade thickness at 5 points at least. In
particular, minimum thickness must
also be ensured in the area of the blade
wings.
● Place a ruler (3) against the front blade
edge and measure permissible
grinding.
Wear limits:
The blade thickness must be at least
1.6 mm at any point.
The cutting edges may not be ground back
by more than 5 mm during sharpening.
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).
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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.
12.6 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).
● Unscrew blade fastening screw (3) and
remove mowing blade (2).
0478 121 9917 E - EN
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