Checking Blade Wear; Maintenance Interval; Removing And Installing Mowing; Sharpening The Mowing Blade - Stihl Rme 339 Gebrauchsanleitung

12.5 Checking blade wear

Maintenance interval:

Before each use
Risk of injury!
Blades are subjected to differing
degrees of wear depending on the
location and duration of use. If you
use the machine 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. A worn blade may break
off and cause serious injuries. The
instructions for blade maintenance
must therefore always be observed.
● Tilt mower upwards into cleaning
position ( 12.2).
● Clean mowing blade (1).
● 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:
Blade thickness: > 1,6 mm
Permissible grinding: < 5 mm
The blade must be replaced,
– if it is damaged (notches, cracks),
– if the measured values are achieved at
one or more points or are outside the
permissible limits.
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If the mulching blade available as a special
accessory is installed on the lawn mower,
different wear limits apply (see instruction
17
manual for accessory).
12.6 Removing and installing
mowing blade
In order to prevent damage to the
blade fastening screw, use a
suitable 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).
2 Installing:
Risk of injury!
The mowing blade must only be
installed as shown, in particular
tabs (6) must face downwards.
Always replace blade fastening
screw (3) when replacing the
mowing blade. The specified torque
when tightening the blade fastening
screw must be strictly observed, as
the secure attachment of the cutting
tool depends on this.
● Clean the blade contact surface and
blade bushing.
● Install mowing blade (2) with curved
wings pointing upwards. Locating
lugs (4) must be located in recesses (5)
of mowing blade.
● Use a suitable wooden block (1) to
counterhold mowing blade (2).
● Apply Loctite 243 to thread of blade
fastening screw (3).
● Tighten blade fastening screw (3).
Tightening torque:
10 - 15 Nm

12.7 Sharpening the mowing blade

If you do not have the necessary expertise
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or auxiliary equipment, you should have
the blade sharpened by a specialist dealer
(STIHL recommends STIHL specialist
dealers). Operation of the machine is
impaired in the case of an incorrectly
sharpened mowing blade (incorrect
sharpening angle, imbalance, etc.).

Sharpening instructions

● Remove the mowing blade. (
● Cool the mowing blade during
sharpening, e.g. with water.
The blade must not be allowed to
display blue colouring, as this would
reduce its cutting quality.
● Sharpen blades evenly to prevent
vibration due to imbalance.
● Observe a sharpening angle of 30°.
● Observe the wear limits (

12.8 Storage (winter break)

Store the machine in a dry and locked
place that is generally free of dust. Make
sure that it is kept out of the reach of
children.
Only store the lawn mower in good
operating condition, fold down the
handlebar if necessary.
Keep all nuts, pins and bolts tightly
fastened, replace danger signs and
warnings on the machine that have
12.6)
12.5).
0478 121 9919 C - EN