User Manual

0478 111 9940 B - EN
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● Standard blade:
Place a ruler (2) against the relevant
blade edge as shown and measure
permissible grinding B.
● Multi-blade (RM 545 VM):
Check minimum width C at the
narrowest point behind the blade wings
using a slide calliper.
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.
1 Wear limits for standard blade:
Blade thickness A: > 2 mm
Permissible grinding B: < 5 mm
2 Wear limits for multi-blade
(RM 545 VM):
Blade thickness A: > 2 mm
Minimum width C: > 55 mm
12.4 Removing and installing the
blade
Removing:
● Use a suitable wooden block (1,
approx. 60x60 mm) to counterhold
blade (2).
● Unscrew blade fastening screw (3)
using an A/F 17 spanner.
● Remove blade (2), blade fastening
screw (3) and retaining washer (4).
Installing:
● Clean the blade contact surface and
blade bushing.
● Check the balance of the blade.
(Ö 12.5)
● Install blade (2) with the curved wings
pointing upwards (towards the
machine).
● Use a suitable wooden block (1,
approx. 60x60 mm) to counterhold
blade (2).
● Install blade fastening screw (3) with a
new retaining washer (4) and tighten.
Tightening torque:
60 - 65 Nm
12.5 Checking the balance of the
blade
● Remove the blade. (Ö 12.4)
● Guide screwdriver (1) through central
bore (2) of blade (3) and align the
mowing blade horizontally.
If the blade is properly balanced it will
remain in this horizontal position.
● If the blade leans to one side, re-
sharpen this side until the blade is
evenly balanced. (Ö 12.6)
12.6 Sharpening the mowing blade
STIHL 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 the mowing blade. (Ö 12.4).
● 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 the sharpening angle of 30°.
● After sharpening, remove any
sharpening burr at the cutting edge
using fine sandpaper if necessary.
● Observe the wear limits. (Ö 12.3)
12.7 Adjusting the self-
propulsion cable
Maintenance interval:
As required
The tension of the cable is adjusted
correctly at the factory.
Adjustment of the cable is necessary
– if, after a lengthy period of use, self-
propulsion does not engage properly
when the self-propulsion lever is
actuated.
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Risk of injury!
The blade (2) must only be installed
as shown. 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 blade fastening
screw (3) with Loctite 243.
Replace retaining washer (4) each
time the blade is installed and blade
fastening screw (3) each time the
blade is replaced.
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