Instruction Manual

0478 216 9907 C - EN
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Remove dirt from the cooling ribs, fan
wheel, area around the air filter, exhaust,
etc. to ensure that the engine is
adequately cooled.
11.3 Blade maintenance
Maintenance interval:
Before each use
● Remove the feed chute. ( 7.8)
● Check the blades for damage (notches
or cracks) and wear; reverse or replace
if necessary.
Wear limits of the blades:
● On the blades, measure the distance
between the bore to the edge of the
blade at several points.
Minimum distance 6mm
Reversing the blades:
● Remove the blade disc. ( 7.6)
● Unscrew screws (1) and remove
together with nuts (2).
● Remove blade (3) upwards.
● Clean the blade disc.
● Reverse blade (3) and place onto the
blade disc with the sharp edge exposed
and align the bores.
● Insert screws (1) through the bores and
screw on nuts (2). Tighten nuts (2) to
22 - -28 Nm.
● Install the blade disc. ( 7.5)
Sharpening the blades:
Blades which are blunt on both sides must
be sharpened before resuming work.
In order to ensure optimum machine
operation, the blades should only be
sharpened by a technician. STIHL
recommends STIHL specialist dealers.
● Remove the blades for sharpening.
● Cool the blades 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.
● Check blades for damage before
installing: the blades must be replaced
if notches or cracks are visible or if the
blades have reached the wear limits.
● Sharpen blades at a sharpening angle
of 30°.
● Sharpen the blades against the cutting
edge.
● After sharpening, remove any
sharpening burr at the cutting edge
using fine sandpaper.
● Observe the tightening torques
contained in the "Reversing the blades"
section when installing the blades.
11.4 V-belt maintenance
Maintenance interval:
Every 10 operating hours
Check the V-belt for wear and damage by
means of a visual inspection and replace if
necessary.
Check V-belt tension and adjust as
required.
Checking V-belt tension:
● Detach the spark plug socket.
● Loosen screws (1), but do not unscrew
fully (remain on belt guard) and remove
belt guard (2).
● Using your thumb, press on the V-belt
between the two V-belt pulleys.
It must be possible to depress the V-
belt by approx. 10 mm.
Adjusting V-belt tension:
● Loosen the engine mounting (not
illustrated):
Loosen 3 bolts of the engine mounting,
but do not remove; counterhold nuts on
upper side.
● Tension the V-belt by turning
adjustment nut (3).
● After adjustment, re-tighten the engine
fastening bolts and install the belt
guard.
Risk of injury!
Always wear thick
gloves.
The blades must be reversed or
replaced before the specified wear
limits are reached. STIHL
recommends STIHL specialist
dealers.
The cutting blades are designed as
reversible blades. This means that
blunt blades can be reversed and
the machine is ready for use again.
Always reverse both blades.
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Insufficient tensioning increases V-
belt wear, excessive tensioning
may lead to bearing damage.
If you do not have the necessary
knowledge to adjust the V-belt, you
should have a technician perform
this work.
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