Stihl 108 User Guide

							\
f\
;:;...CD8o
I
~
Beforecutting, inspect
the area forstones, glass,
pieces ofmetal, trashor
other solidobjects. The
cutting attachment couldthrow objects
of this kind.
~.
Toreduce the
. riskofinjury
from thrown
objects and
blade contact,
never operate abrushcutter withouta
properly mounted deflector. Keepthe
skirt onthe deflectors adjustedproperly
at all times (seechapter
onmounting the
various cuttingtoolsofyour owners
manual). Donot overreach. Keepproper
footing andbalance atall times.
Working Conditions
Operateandstart your brushcutter only
outdoors
ina ventilated area.Operate
the brushcutter undergoodvisibility
and daylight conditions only.Work
carefully.
Always holdthebrushcutter firmlywith
both hands. Wrapyourfingers tightly
around thehandles, keeping thehand­
les cradled between yourthumb and
forefinger. Keepyourhands
inthispositi­
on, tohave yourbrushcutter undercon­
trol atall times. Makesureyour brush­
cutter handles andgripare
ingood con­
dition andfreeofmoisture, pitch,oilor
grease.
10
Warningl
Never attempttooperate anybrush
cutter withonehand. Lossofcontrol of
the brushcutter resulting
inseriousor
fatal injury mayresult.
Toreduce therisk ofbodily injury
resulting fromlossofcontrol andcontact
with thecutting tool,make sureyour
unif:­
isequipped withtheproper handleana
harness forthe type ofcutting attach­
ment being used(seechart
inchapter
on Selecting theCutting Tool).
Special caremust betaken
inslippery
conditions (wetground, snow)and
in
difficult, over-grown terrain.Watchfor
hidden obstacles suchastree stumps,
roots andditches toavoid stumbling.
Waming
This brushcutterisnormally tobe used
at ground levelwiththecutting attach­
ment parallel
totheground. Useofa
brush cutter above ground levelorwith
the cutting attachment perpendicular
to
theground mayincrease therisk of
injury, sincethecutting attachment
is
morefullyexposed andthebrushcutter
may bemore difficult
tocontrol. Never
use your brushcutter asahedge
trimmer. 
						

							Wmmg!
Whenusingrigidblades, avoidcutting
close tofences, sidesofbuildings, tree
trunks, stones orother suchobjects
that could cause thebrushcutter tokick
out orcould cause damage tothe
blade. STIHLrecommends useofthe
nylon lineheads orPolycut headfor
such jobs.
Inaddition, bealert toan
increased possibility ofricochets
in
such situations.
Do not operate usingthestarting
throttle lockasyou donot have control
of the engine speed. Seesection ofyour
owners manualonthe proper useofthe
slide control.
Ifthecutting toolordeflector becomes
clogged orstuck, always turnoffthe
engine andmake surethecutting tool
has stopped, beforecleaning. Grass,
weeds, etc.should becleaned offthe
cutting toolatregular intervals.
Warning!
DuringCUlling, checkthetightness and
the condition ofthe cutting toolat
regular intervals.
Ifthebehavior ofthe
tool changes, stoptheengine immedi­
ately, andcheck thenutsecuring
the tool fortightness andthecutting tool
for cracks anddamage.
Replace cracked, bent,warped, dam
aged ordull cutting toolsimmediately.
Such toolsmayshatter athigh speed
and cause serious orfatal injury.
Warnng
Aloose blade maycause thebladeto
vibrate, crack,breakorcome offthe
brushcutter, whichmayresult
in
serious orfatal injury. Makesurethat
the blade isproperly tightened. Usethe
wrench supplied orone ofsufficient
length toobtain theproper torque.
Ifthe
blade loosens afterbeing properly
tightened, stopwork immediately. The
retaining nutmay beworn ordamaged
and should bereplaced. Neveruse
unauthorized partstosecure theblade.
Iftheblade continuestoloosen, see
your STIHL dealer. Neverusea
brushculler withaloose blade.
Important adjustments
amlng
Toreduce therisk ofpersonal injuryfrom
loss ofcontrol orcontact withtherun­
ning grass cutting blade,donot use a
grass cutting bladewithincorrect idle
adjustment. Atcorrect idlespeed, the
grass cutting bladeshould notmove.
For directions toadjust idlespeed, see
the appropriate sectionofyour owners
manual.
Ifyou cannot setthe correct idlespeed,
have yourSTIHL dealercheckyour
brushcutter andmake proper
adjustments orrepairs.
Waming
Never toucharotating cuttingtoolwith
your hand orany part ofyour body. It
continues torotate forashort period
after thethrottle trigger
isreleased
(flywheel effect). 
						

							Operatinginstructions
(jG
wamln
91
oImproper
useofany
~brush-cutter can
cause serious or
fatal personal injury.Read, understand
and follow allsafety instructions
inyour
owners manualbeforeoperating these
products.
Toreduce therisk ofpersonal
injury
tothe operator fromblade con­
tactand thrownobjects, makesureyour
unit
isequipped withtheproper de­
flector, handle andharness forthe type
of cutting attachment beingused(see
chart
inchapter onSelecting theCut­
ting Tool). Always wearproper eyepro­
tection.
12
11111.111.111.11,111.11111..11.1,1111111112;;11111111.11111rl,1111111111111.III,11111,1111111111,lh9;.IIIIIIIII1111,I1111,111i1I1,111,:1111,111,1,,111,8
						

							f
STIHLPolymaticmowinghead
Frayed line
isreplaced byasimple
adjustment (seeinstruction sheet
supplied withmowing head).
STIHL
Autocutmowinghead
Nylon cutting cordadvances automat­
ically when tapped against theground.
STIHL
Polycutmowinghead
Important!
Three rectangular wearlimitmarks are
applied tothe base (periphery)
ofthe
Polycut.
Toreduce therisk ofserious
injury frombreakage ofthe head or
blades, thePolycut mustnotbeused
I,I'~1111111111111111111111,,Il,illIi!1I2j;lIlIll,/111111111111111111:IIIJ,i1It1,,:11111111..IIi
						

							Usingthebrush knife
Whenfittedtothebrushcutter, the
brush knife
issuitable forapplications
ranging fromcutting matted grassto
clearing weeds,wildgrowth andscrub.
Tocutwild growth andscrub, lowerthe
rotating brushknifedown ontothe
growth toachieve achopping effect.
Use thebrushcutter likeascythe tocut
grass,
i.e.sweepitto and froinanarc.
Warning!
When cutting woodymaterials, usethe
left side ofthe blade toavoid kickout
(blade thrust) situations.
14
Warnlngl
Improper useofabrush knifemay
cause
itto crack, chiporshatter. Thrown
parts mayseriously injuretheoperator
or bystanders.
Toreduce therisk of
personal injury
itisessential totake the
following precautions:
Avoid contact withhard orsolid foreign
objects suchasstones, rocksorpieces
of metal.
Nevercut wood orshrubs withastem
diameter ofmore than2cm (3/4) -
use acircular sawblade forsuch work.
Inspect thebrush knifeatregular short
intervals forsigns ofdamage. Donot
continue workingwithadamaged brush
knife. Resharpen thebrush knifere­
gUlarly (when
ithasdulled noticeably).
Warning!
Whencutting youngsaplings orother
woody materials up
to2cm(3/4)in
diameter, useleftside ofthe bladeto
avoid kickout situations (see
appropriate section
inthismanual). Do
not attempt tocut woody material witha
larger diameter, sincetheblade may
catch orjerk thebrushcutter forward.
This maycause damage
totheblade or
brushcutter orloss ofcontrol ofthe
brushcutter, resulting
inpersonalinjury 
						

							ToredUcetherisk ofserious injury
to
theoperator orbystanders bya
kickout, neveruseacircular sawblade
on abrushcutter withaloop handle.
by
experienced operatorswithspeciali­
zed training
inuseand control ofthe
brushcutter.
amlngl
The riskofkickout ishighest when
cutting inthe darker shaded area.
To
reducetherisk ofkickout andresulting
injury, donot use thisarea ofthe
circular sawblade forcutting treesor
shrubs. Specialtechniques usingthe
lighter shaded areasofthe blade tocut
shrubs andtrees should only
beused
Before
starting thecut, accelerate the
engine up
tofullthrottle. Perform cut
with uniform pressure. STIHLrecom­
mends thatthecircular sawblade be
applied tothe right ofthe tree, using
the non-shaded areaofthe blade.
Warning
Inordertoreduce
therisk ofinjury from
thrown objects
orfromoperator
contact withthecutting tool,besure
to
remount thestandard deflectorforall
other
u·ses.
No
						

							N;;~§
Riskofkickout (bladethrust)
with allrigid cutting blades
Warning
l
Kickout (bladethrust) isthe sudden and
uncontrolled motiontowards theopera­
tors rightorrear thatcanoccur when
the shaded areaofthe rotating blade
comes
incont
						

							Checkcondition ofculling toolatregular
short intervals.
Ifbehavior oftool
changes, checkitimmediately for
tightness orany signs ofcracks
inpar­
ticular. Replace damaged ordull cUlling
tools immediately, evenifthey have only
superficial cracks.
Iftheblade loosens
after being properly tightened, the
retaining nutmay beworn ordamaged
and should bereplaced.
Ifthe blade
continues
toloosen, seeyour STIHL
dealer. Donot attach anyblade toaunit
without properinstallation ofall required
parts. Never useunauthorized partsto
secure theblade. Failure touse the
proper partsmaycause theblade
tofly
offand seriously injuretheoperator or
bystanders.
Check fuelfiller capforleaks atregular
intervals. Usethespecified sparkplug
and make sure
itandtheignition lead
are always
ingood condition.
Warning!Donotoperate yourbrushcutter ifthe
muffler
isdamaged, missingormode­
fied. Animproperly maintained muffler
will increase therisk offire and hearing
loss. Never touchahot muffler orburn
willresult.Ifyour muffler wasequipped
with aspark-arresting screen
toreduce
the risk offire (e.g.
intheUSA, Canada
and Australia), neveroperate yourhedge
trimmer ifthe screen
ismissing ordama­
ged. Remember thattherisk offorest
fi­
res isgreaterinhot ordry weather.
Warning!Inordertoreduce therisk offire, donot
modify orremove anypart ofthe muffler
or spark arrestor.
Keep cutting toolsharp. Tighten allnuts,
bolts andscrews exceptthecarburetor
adjustment screwsaftereach use.
Keep spark plugandwire connection
tight andclean. Thespark plugelectrode
gap should bechecked withafeeler
gauge atleast every 50operating hours
and reset
ifnecessary. Fitanew spark
plug
ifthe electrodes arebadly pilled.
Store brushcutter
inadry, high orlocked
location placeandoutofreach of
children. Before storing forlonger thanafew
days, always emptythefuel tank.
WarnlnglKeep hands andfeetaway fromcUlling
tool.
17 
						

							SelectingtheCuttingTool
Cuttingtools:
1STIHL Supercut20-1mowing head
(FS
74only)
2 STIHL Supercut 20-2mowing head
3 STIHL
Autocut 20-2mowing head
(FS
74only)
4 STIHL Autocut 24-2mowing head
5 STIHL Autocut 25-2mowing head
6 STIHL Autocut 30-2mowing head
7 STIHL Polymatic 30-2mowing head
8 STIHL
Polycut 20-3mowing head
9 STIHL
FixedLinehead
10 Grass
Cutting blade230-4
11Grass Cutting blade230-8
12 Brush knife250
13 Circular
sawblade 200
(scratcher tooth)
14 Circular sawblade 200
(chisel tooth)
Deflectors:
15 Deflector formowing heads
16 Deflector
for
allcuttingtools
with
17Skirt andlinelimiting blade
18 Deflector for
allcuttingtools
withoutskirtandlinelimiting blade
19 Stop
forcircular sawblades
Handles:
20 Loop handle
21Loophandlewith
22Standoff lever
23 Bike handle
18 Carrying
straps:
24Shoulderstraprecommended
25 Shoulder strap
26 Fullharness recommended
27 Fullharness
A fully equipped brushcutter comprises,
among otheritems:
- Cutting tool
- Deflector
- Handle
- Carrying strap
Select the
correctcombinationfrom
the table
accordingtothecuttingtool
youintendtouse:
For safety reasons, youmay onlycombi­
nethecutting tool,deflector, handleand
carrying strapversions shownwhenyou
read thetable
horizontallyfrom leftto
right
Othercombinations,e.g.reading the
table diagonally, are
notpermitted
sincethereisotherwiseariskof:-
seriousinjury.
Warning
STIHL brushcutters withaloop handle
withoutstandofflever maybeused
only with
theabove-mentioned mowing
heads withnylon lineorplastic blades.
Other plastic ormetal cutting toolsmay
only
beusedonbrushcutters withabike
handle, J-handle orloop handle
with
standoffleverinordertominimize the
risk ofpersonal injurythrough contact
with thecutting tool. 
						

							Cuttingtools Deflectors HandlesCarrying
straps
2
0
20~~---'
15
34~21
~
~-
5 6 22
24
16
7 8
23
V
~l
t-J(eC(~.....-
9
25
101121
~
)-:1--\18
~.~--..../J22
12 23
V
AI....2526
19
~
1314
~
23
V
0(:)
=
27
19