Flywheel - Stihl 4180 Series Manual

7.7

Flywheel

4
3
2
1
: Crankshaft (1) and flywheel (2)
are an interference fit.
The crankshaft and flywheel are
pressed together with such force
that the flywheel cannot turn on the
crankshaft.
For this reason the mating
surfaces must be free from
grease and oil.
The conical interference fit ensures
the flywheel is exactly centered, and
runs smoothly with a minimum of
runout.
: The key (3) is used only to
position the flywheel in relation to
the crankshaft (correct ignition
timing).
: The nut (4) pushes the flywheel
(2) onto the crankshaft (1) to
achieve the required interference
fit.
40
1
– Remove the clutch, b 7.6.1
: Remove the hex. nut (1).
3
: Mount puller (1) 4119 890 4501
to the flywheel with M6 x 25
screws (2 and 3), and pull off the
flywheel.
1
: There must be no signs of cracks
or other damage on the flywheel
(1) and magnet poles (2).
If this is the case, install a new
flywheel.
Installing the flywheel
– Clean the stub of the crankshaft
and the flywheel hub bore with a
standard commercial, solvent-
based degreasant containing no
chlorinated or halogenated
hydrocarbons, b 12
– Check Woodruff key or integrally
cast key for damage and replace
key or flywheel if necessary.
1 2
: Fit the flywheel in position.
Make sure it is properly seated.
Key (1) in flywheel must engage
slot in crankshaft stub.
2
: Fit the hex. nut (1) and tighten it
down firmly, b 3.4
– Install the clutch, b 7.6.2
1
1
Series 4180 Powerhead