Checking Blade Wear; Removing And Installing The Blade - Viking MB 650 VE Instruction Manual

● Hold the console with your left hand as
shown and hold the discharge flap
open. At the same time, press detent
lever (3) with your thumb and hold.
● Hold the machine with your right hand
by the front carrying handle and tilt it
slowly backward until the handlebar
touches the ground as shown.
● Release discharge flap (2) and detent
lever (3) and check that the machine is
standing securely.
Notes on cleaning:
● Clean off dirt using little water, with a
brush or with a cloth. Never spray water
onto engine components, seals or
bearing points. If necessary, use a
special cleaner (e.g. STIHL special
cleaner).
● First, remove accumulated clipping
deposits using a stick.
● Always clean the mowing blade – under
no circumstances should you hit the
mowing blade (e.g. with a hammer) to
loosen dirt.
● Clean the engine cooling ribs.
● Clean the grass catcher box and mulch
insert using running water and a brush
well away from the machine.
60

14.3 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 the mower upwards into the
cleaning position. ( 14.2)
● Clean mowing blade (1).
● Use a slide calliper to measure blade
thickness A at 5 points at least. In
particular, minimum thickness must
also be ensured in the area of the blade
wings.
● Check the minimum width B at the
narrowest point behind the blade wings
using a slide calliper.
Blade thickness A: > 2,0 mm
Minimum width B: > 55 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.
If an accessory blade is installed on the
lawn mower, different wear limits apply
(see accessory instruction manual).
14.4 Removing and installing the
blade
26
Removing the blade:
● Tilt the mower upwards into the
cleaning position. (
● Hold blade (1) and unscrew blade
fastening screw (2).
● Remove blade (1), blade fastening
screw (2) and retaining washer (3).
Installing the blade:
Risk of injury!
The blade (1) must only be installed
as shown. The tabs (4) must face
downwards and the curved wings
must point upwards.
Observe the specified tightening
torque for the blade fastening
screw, as the secure attachment of
the cutting tool depends on this.
Additionally secure blade fastening
screw (2) with Loctite 243.
Replace spring washer (3) each
time the blade is installed and blade
fastening screw (2) each time the
blade is replaced.
● Clean the blade contact surface and
blade bushing or blade holder.
● Position blade (1) on the blade bushing
or blade holder (5) with the curved
wings pointing upwards (towards the
machine).
● Fit a new retaining washer (3) as
shown, screw in and tighten blade
fastening screw (2).
Tightening torque:
60 - 65 Nm
27
14.2)
0478 111 9931 D - EN