Stihl MS 151 TC Instruction Manual [en, fr]
STIHL MS 151 TC
Instruction Manual
Notice d’emploi
G Instruction Manual
1 - 44
F Notice d’emploi
45 - 93
Contents
English
Guide to Using this Manual 2
Safety Precautions 3
Reactive Forces 9
Working Techniques 10
Cutting Attachment 11
Mounting the Bar and Chain 12
Tensioning the Saw Chain (side
chain tensioner) 13
Original Instruction ManualPrinted on chlorine-free paper
Checking Chain Tension 14
Fuel 14
Fueling 15
Chain Lubricant 17
Filling Chain Oil Tank 17
Checking Chain Lubrication 18
Chain Brake 18
Starting / Stopping the Engine 19
Operating Instructions 22
Taking Care of the Guide Bar 23
Cleaning the Air Filter 24
Engine Management 24
Adjusting the Carburetor 25
Spark Plug 26
Printing inks contain vegetable oils, paper can be recycled.
Storing the Machine 27
Checking and Replacing the Chain
Sprocket 27
Maintaining and Sharpening the
Saw Chain 28
Maintenance and Care 32
Main Parts 34
Specifications 36
Special Accessories 37
Ordering Spare Parts 37
Maintenance and Repairs 37
Disposal 38
Important Safety Instructions 38
Key to Symbols 40
STIHL Limited Emission Control
Warranty Statement 41
CSA Standard 43
Dear Customer,
Thank you for choosing a quality
engineered STIHL product.
It has been built using modern
production techniques and
comprehensive quality assurance.
Every effort has been made to ensure
your satisfaction and trouble-free use of
the product.
Please contact your dealer or our sales
company if you have any queries
concerning this product.
Your
Dr. Nikolas Stihl
© ANDREAS STIHL AG & Co. KG, 2020
0458-508-8221-A. VA1.H20.
0000008726_002_GB
MS 151 TC
This instruction manual is protected by copyright. All rights reserved, especially the rights to reproduce, translate and process
with electronic systems.
1
English
Guide to Using this Manual
This Instruction Manual refers to a
STIHL chain saw, also called a machine
in this Instruction Manual.
Pictograms
Pictograms that appear on the machine
are explained in this Instruction Manual.
Depending on the machine and
equipment version, the following
pictograms may appear on the machine.
Fuel tank; fuel mixture of
gasoline and engine oil
Tank for chain oil; chain
oil
Engage and release
chain brake
Coasting brake
Intake air baffle: winter
operation
Intake air baffle: summer
operation
Handle heating
Actuate decompression
valve
Actuate manual fuel
pump
Symbols in text
WARNING
Warning where there is a risk of an
accident or personal injury or serious
damage to property.
Engineering improvements
STIHL's philosophy is to continually
improve all of its products. For this
reason we may modify the design,
engineering and appearance of our
products periodically.
Therefore, some changes, modifications
and improvements may not be covered
in this manual.
Direction of chain travel
Ematic; chain oil flow
adjustment
Tension saw chain
2
NOTICE
Caution where there is a risk of
damaging the machine or its individual
components.
MS 151 TC
English
Safety Precautions
This special chain
saw shall be used
only by persons
who are trained in
special cutting and
working
techniques.
Due to the special handle
design (closely spaced
handles) there is an
increased risk of injury
using this kind of saw (cut
injuries due to uncontrolled reactive forces of
the chain saw). Special
safety precautions must
be observed to reduce
the risk of personal injury
when working with a
chainsaw because of the
very high chain speed
and very sharp cutters.
It is important that you
read the instruction manual before first use and
keep it in a safe place for
future reference. Nonobservance of the
instruction manual may
result in serious or even
fatal injury.
General
Observe all applicable local safety
regulations, standards and ordinances.
The use of noise emitting power tools
may be restricted to certain times by
national or local regulations.
If you have not used this model before:
Have your dealer or other experienced
user show you how to operate your
machine or attend a special course in its
operation.
Minors should never be allowed to use a
chainsaw. Exceptions to this rule are
young persons older than 16 who have
been trained in special cutting
techniques with the tree surgery saw.
Keep bystanders, especially children,
and animals away from the work area.
The user is responsible for avoiding
injury to third parties or damage to their
property.
Do not lend or rent your chain saw
without the instruction manual. All users
must be specially trained in tree surgery
work with a tree surgery saw and be
familiar with this model and its operation.
To operate a chain saw you must be
rested, in good physical condition and
mental health. If you have any condition
that might be aggravated by strenuous
work, check with your doctor before
operating a chainsaw.
Do not operate the chain saw if you are
under the influence of any substance
(drugs, alcohol) which might impair
vision, dexterity or judgment.
To reduce the risk of accidents or injury,
put off the work in poor weather
conditions (rain, snow, ice, wind).
Persons with pacemakers only: The
ignition system of your chainsaw
produces an electromagnetic field of a
very low intensity. This field may
interfere with some pacemakers. To
reduce health risks, STIHL recommends
that persons with pacemakers consult
their physician and the pacemaker
manufacturer before operating this
power tool.
Intended Use
Tree surgery chainsaws are specialpurpose saws equipped with a top
handle. They are designed specifically
for tree surgery and maintenance in the
crown of the standing tree.
Chainsaw operators must be properly
secured while working in a tree (e.g. lift
bucket, personal safety equipment,
safety harness).
The chainsaw may be used for cutting
wood and wooden objects only.
It must not be used for any other
purpose because of the increased risk of
accidents.
They must not be used for felling trees or
cutting firewood. Normal chainsaws with
wider spaced handles are
recommended for such operations.
Never attempt to modify your saw in any
way since this may increase the risk of
personal injury. STIHL excludes all
liability for personal injury and damage
to property caused while using
unauthorized attachments.
This chainsaw is designed for tree
maintenance work, e.g. pruning small
branches. For this reason it comes
standard without a spiked bumper. A
spiked bumper (available as special
accessory) may be mounted if required.
MS 151 TC
3
English
0012BA024 KN
Clothing and Equipment
Wear proper protective clothing and
equipment.
Clothing must be sturdy
and snug-fitting, but allow
complete freedom of
movement. Wear snugfitting clothing with cutretardant pads for feet,
legs, hands and forearms
– an overall, not a loosefitting jacket.
Avoid clothing that could get caught on
branches, brush or moving parts of the
machine. Do not wear a scarf, necktie or
jewelery. Tie up and confine long hair
(headscarf, cap, hard hat, etc.).
Wear suitable safety
shoes – with cut-retardant material, non-slip
soles and steel toe caps.
WARNING
To reduce the risk of eye
injuries, wear tight-fitting
safety goggles conforming to standard EN 166.
Make sure that the safety
goggles fit correctly.
Wear a face shield and make sure it fits
correctly.
Wear "personal" hearing protection – for
example, ear defenders.
Wear a hard hat with a chin strap
wherever there is any risk of falling
objects.
Wear sturdy protective
gloves made of a resistant material (e.g. leather)
– with cut-retardant
material.
STIHL can supply a comprehensive
range of personal protective clothing
and equipment.
Use a personal fall arrest system.
Use only certified equipment that is
suitable for the application concerned.
Check the condition of the equipment
before use and replace broken parts.
Transporting
Always stop the engine, engage the
chain brake and fit the chain guard
(scabbard) before carrying the saw short
distances. This avoids the risk of the
chain running unintentionally.
Always carry the saw by the control
handle – with the hot muffler away from
your body – the guide bar must point to
the rear. To reduce the risk of serious
burn injuries, avoid touching hot parts of
the machine, especially the surface of
the muffler.
In vehicles: Properly secure your saw to
prevent turnover, fuel spillage and
damage.
Cleaning
Clean plastic parts with a cloth. Harsh
detergents can damage the plastic.
Clean the dust and dirt off the machine –
do not use any grease solvents for this
purpose.
Clean the ventilation slots if necessary.
Do not use a high-pressure cleaner to
clean the machine. The hard jet of water
can damage parts of the machine.
Accessories
Only use those tools, guide bars, chains,
chain sprockets, accessories or
technically equivalent components that
have been approved by STIHL for this
machine. If you have any questions in
this respect, consult a servicing dealer.
Use only high quality tools and
accessories. Otherwise, there may be a
risk of accidents and damage to the
machine.
STIHL recommends the use of genuine
STIHL tools, guide bars, chains, chain
sprockets and accessories. They are
specifically designed to match your
model and meet your performance
requirements.
Refuelling
Gasoline is an extremely
flammable fuel – keep
clear of naked flames and
fire – do not spill any fuel
– no smoking.
Switch off the engine before refuelling.
4
MS 151 TC
English
Never refuel the machine while the
engine is still hot – the fuel may spill over
– risk of fire!
Open the fuel filler cap carefully so that
any excess pressure is relieved
gradually and fuel does not splash out.
The machine may only be refuelled in a
well ventilated place. Clean the machine
immediately if fuel is spilled. Do not spill
fuel over your clothing – contaminated
clothing must be changed immediately.
The machines can be equipped with the
following filler caps as standard:
Cliplock filler cap (bayonet-type)
Place the cliplock filler
cap (bayonet-type) in
position, turn as far as
stop and fold the cliplock
down.
This helps reduce the risk of unit
vibrations causing an incorrectly
tightened filler cap to loosen or come off
and spill quantities of fuel.
Look out for leaks! Never
start the engine if fuel has
been spilled or is leaking
– Fatal burns may result!
Before Starting Work
Check that your saw is properly
assembled and in good condition – refer
to appropriate chapters in the instruction
manual.
– Check the fuel system for leaks,
paying special attention to visible
parts such as the tank cap, hose
connections and the manual fuel
pump (on machines so equipped). If
there are any leaks or damage, do
not start the engine – risk of fire.
Have your saw repaired by a
servicing dealer before using it
again.
– Check operation of chain brake,
front hand guard
– Correctly mounted guide bar
– Correctly tensioned chain
– The trigger and trigger lockout must
move freely and spring back to the
idle position when they are
released.
– Master Control lever must move
easily to STOP, 0 or †
– Check that the spark plug boot is
secure – a loose boot may cause
arcing that could ignite combustible
fumes and cause a fire.
– Never attempt to modify the controls
or safety devices in any way.
– Keep the handles dry and clean –
free from oil and dirt – for safe
control of the saw.
– Make sure there is sufficient fuel
and chain oil in the tanks.
To reduce the risk of personal injury, do
not operate your saw if it is damaged or
not properly assembled.
Starting the Saw
Start the saw on level ground only. Make
sure you have a firm footing. Hold the
saw firmly. To reduce the risk of injury
from the rotating chain, check that the
cutting attachment is not touching any
object or the ground .
The chainsaw is a one-person saw. Do
not allow other persons in the work area
– even when starting.
Do not attempt to start the saw when the
saw chain is in a cut.
Starting the saw in a tree is very
dangerous since the user may lose
control of the machine – risk of injury.
The tree surgery saw should be
checked, fueled, started and warmed up
by an assistant on the ground before it is
transported up to the operator in the
tree.
Start the engine at least 3 meters from
the fueling spot, outdoors only.
To reduce risk of chain rotation and
personal injury, lock the chain with the
chain brake before starting.
Do not drop start the power tool – start
the engine as described in the
instruction manual.
MS 151 TC
5
English
0012BA019 KN
H
L
During Operation
When working in the tree, always secure
the chainsaw with a rope – tie it to the
ring and attach it to the lifeline. Always
engage the chain brake before letting
the chainsaw hang by the rope.
To reduce the risk of
accidents and injuries,
always hold your saw
firmly with both hands:
Right hand on the control
handle, even if you are
left-handed. To ensure
safe control, wrap your
fingers tightly around
both handles.
One-handed operation is
particularly dangerous,
e.g. when cutting dry,
knotty and dead wood,
the chain may not enter
the cut properly. The
resultant reactive forces
may cause the saw to
skate or bounce on the
limb and slide out of control. This increases the
risk of serious or even
fatal injury.
Use the tree surgery chainsaw with one
hand only:
– if two-handed cutting is not possible
and
– if one hand is required for support
during the cut and
– if the saw is held firmly and
– if all parts of your body are clear of
the cutting attachment.
During one-handed cutting:
– never support yourself on the limb
being cut
– never cut with the bar nose
– never attempt to hold falling limbs
Make sure you always have good
balance and secure footing. To avoid
slipping, take special care when the bark
is wet.
In the event of impending danger or in
an emergency, switch off the engine
immediately – move the Master Control
lever in the direction of STOP, 0 or †.
Never leave a running saw unattended.
Take special care in slippery conditions
– damp, snow, ice, on slopes, uneven
ground and freshly debarked logs.
Watch out for obstacles such as tree
stumps, roots and ditches which could
cause you to trip or stumble.
Do not work alone – keep within calling
distance of other persons trained in first
aid who can provide assistance in an
emergency. Helpers at the cutting site
must also wear protective clothing (hard
hat) and stand well clear of the branches
being cut.
Be particularly alert and cautious when
wearing hearing protection because
your ability to hear warnings (shouts,
alarms, etc.) is restricted.
To reduce the risk of accidents, take a
break in good time to avoid tiredness or
exhaustion.
The dusts (e.g. sawdust), vapor and
smoke produced during operation may
be dangerous to health. If dust levels are
very high, wear a suitable respirator.
When the engine is running: Note that
the chain continues to rotate for a short
period after you let go of the throttle
trigger (flywheel effect).
To reduce the risk of fire, do not smoke
while operating or standing near your
chainsaw. Note that combustible fuel
vapor may escape from the fuel system.
Check the saw chain at regular short
intervals during operation or
immediately if there is a noticeable
change in cutting behavior:
– Shut off the engine and wait until the
chain comes to a complete
standstill.
– Check condition and proper
mounting.
– Check sharpness.
Do not touch the chain while the engine
is running. If the chain becomes jammed
by an obstruction, switch off the engine
immediately before attempting to
remove the obstruction – risk of injury.
Always shut off the engine before
leaving the saw unattended.
Shut off the engine before changing the
saw chain. This avoids the risk of injury
from the engine starting unintentionally.
6
MS 151 TC
English
To reduce risk of fire, keep hot exhaust
gases and hot muffler away from easily
combustible materials (e.g. wood chips,
bark, dry grass, fuel). Mufflers with a
catalytic converter can become
particularly hot.
Never operate your saw without proper
chain lubrication – check oil level
regularly during operation. Stop work
immediately if the oil level is too low and
refill the oil tank – see also chapters on
"Filling Chain Oil Tank" and "Checking
Chain Lubrication".
If your saw is subjected to unusually
high loads for which it was not designed
(e.g. heavy impact or a fall), always
check that it is in good condition before
continuing work – see also "Before
Starting Work".
Check the fuel system in particular for
leaks and make sure the safety devices
are working properly. Do not continue
operating your saw if it is damaged. In
case of doubt, have the unit checked by
your servicing dealer.
Make sure the idle speed setting is
correct. The chain must not run when
the engine is idling with the throttle
trigger released. Check and correct the
idle speed setting regularly. It the chain
continues to rotate when the engine is
idling, have your dealer make proper
adjustments or repairs.
The chain saw produces
poisonous exhaust gases
as soon as the engine
starts. These gases may
be colourless and odourless and may contain
unburnt hydrocarbons
and benzene. Never work
with the machine indoors
or in poorly ventilated
areas, even if your
machine is equipped with
a catalytic converter.
Ensure proper ventilation when working
in trenches, hollows or other confined
locations – risk of fatal injury from
breathing toxic fumes!
If you feel sick, have a headache, vision
problems (e. g., your field of vision gets
smaller), hearing problems, dizziness or
inability to concentrate, stop work
immediately. Such symptoms may be
caused by an excessively high
concentration of exhaust emissions –
risk of accident!
After finishing work
Switch off the motor, engage the chain
brake and attach the chain scabbard.
Storage
When the machine is not in use, it
should be stored in such a way that noone is endangered. Secure the machine
against unauthorised use.
Store the machine in a safe, dry room.
Vibrations
Prolonged use of the power tool may
result in vibration-induced circulation
problems in the hands (whitefinger
disease).
No general recommendation can be
given for the length of usage because it
depends on several factors.
The period of usage is prolonged by:
– Hand protection (wearing warm
gloves)
– Work breaks
The period of usage is shortened by:
– Any personal tendency to suffer
from poor circulation (symptoms:
frequently cold fingers, tingling
sensations).
– Low outside temperatures.
– The force with which the handles
are held (a tight grip restricts
circulation).
Continual and regular users should
monitor closely the condition of their
hands and fingers. If any of the above
symptoms appear (e.g. tingling
sensation in fingers), seek medical
advice.
Maintenance and repairs
Always switch off the engine before any
repair, cleaning or maintenance work
and any work on the chain. Risk of injury
if the engine starts inadvertently!
Exception: adjustment of carburettor
and idle speed.
MS 151 TC
7
English
The machine must be serviced regularly.
Do not attempt any maintenance or
repair work not described in the
Instruction Manual. All other work should
be carried out by a servicing dealer.
STIHL recommends that maintenance
and repair work be carried out only by
authorised STIHL dealers. STIHL
dealers receive regular training and are
supplied with technical information.
Use only high-quality spare parts.
Otherwise, there may be a risk of
accidents and damage to the machine. If
you have any questions in this respect,
consult a servicing dealer.
Do not modify the machine in any way –
this may increase the risk of personal
injury –risk of accidents!
To reduce the risk of fire due to ignition
outside the cylinder, move the master
control level to STOP, 0 or † before
turning the engine over on the starter
when the spark plug boot is removed or
the spark plug is unscrewed!
Do not service or store the machine near
a naked flame – risk of fire due to the
fuel.
Check fuel cap regularly for tightness.
Use only spark plugs that are in perfect
condition and have been approved by
STIHL – see "Specifications".
Check ignition lead (insulation in good
condition, secure connection).
Check that the muffler is in perfect
working condition.
Do not use the machine if the muffler is
damaged or missing – risk of fire,
damage to hearing!
Never touch a hot muffler – risk of burns!
The condition of the anti-vibration
elements influences vibration behaviour
– inspect anti-vibration elements
periodically.
Inspect chain catcher – replace if
damaged.
Switch off the engine
– To check the chain tension
– To retension the chain
– To replace the chain
– For remedying malfunctions
Observe sharpening instructions – for
safe and proper handling, always keep
the chain and guide bar in flawless
condition. Keep the chain properly
sharpened, tensioned and well
lubricated.
Change chain, guide bar and chain
sprocket in due time.
Regularly check that the clutch drum is
in perfect working condition.
Always store fuel and chain lubricant
only in the specified type of containers
and ensure they are correctly labelled.
Store in a dry, cool and secure place
protected against light and sunlight.
In the event of a chain brake
malfunction, switch off the machine
immediately – risk of injury! Consult a
servicing dealer – do not use the
machine until the malfunction has been
remedied, see "Chain brake".
Maintenance, replacement, or repair of
the emission control devices and
systems may be performed by any
nonroad engine repair establishment or
individual. However, if you make a
warranty claim for a component which
has not been serviced or maintained
properly, STIHL may deny coverage.
For any maintenance please refer to the
maintenance chart and to the warranty
statement near the end of the instruction
manual.
8
MS 151 TC
English
0012BA022 KN
H
L
001BA257 KN
001BA037 KN
A
Reactive Forces
The most common reactive forces that
occur during cutting are: kickback,
pushback and pull-in.
Dangers of kickback
Kickback can result in
serious or fatal injury.
Kickback occurs, e.g.
– when the upper quadrant of the bar
nose unintentionally contacts wood
or another solid object, e.g. when
another limb is touched accidentally
during limbing.
– when the chain at the nose of the
guide bar is pinched in the cut.
QuickStop chain brake:
This device reduces the risk of injury in
certain situations – it cannot prevent
kickback. If activated, the brake stops
the saw chain within a fraction of a
second –
for a description of this device refer to
chapter on "Chain Brake" in this manual.
– Do not cut with the bar nose.
– Take special care with small, tough
limbs, they may catch the chain.
– Never cut several limbs at once.
– Do not overreach.
– Never cut above shoulder height.
– Use extreme caution when re-
entering a previous cut.
– Do not attempt plunge cuts if you
are not experienced in this cutting
technique.
– Be alert for shifting of the log or
other forces that may cause the cut
to close and pinch the chain.
– Always cut with a correctly
sharpened, properly tensioned
chain – the depth gauge setting
must not be too large.
– Use a low kickback chain and a
narrow radius guide bar.
Pull-in (A)
Kickback occurs when the saw is
suddenly thrown up and back in an
uncontrolled arc towards the operator.
MS 151 TC
To reduce the risk of kickback
– Work cautiously and avoid
situations which could cause
kickback.
– Hold the saw firmly with both hands
and maintain a secure grip.
– Always cut at full throttle.
– Be aware of th e location of the guide
bar nose at all times.
Pull-in occurs when the chain on the
bottom of the bar is suddenly pinched,
caught or encounters a foreign object in
the wood. The reaction of the chain pulls
the saw forward – to reduce this risk,
always engage the spiked bumper
securely in the tree or limb.
9
English
001BA038 KN
B
9923BA034 KN
001BA064 LÄ
Pushback (B)
Pushback occurs when the chain on the
top of the bar is suddenly pinched,
caught or encounters a foreign object in
the wood. The reaction of the chain
drives the saw straight back toward the
operator – to avoid this risk:
– Be alert to situations that may cause
the top of the guide bar to be
pinched
– Do not twist the guide bar in the cut.
Working Techniques
Cutting
Do not operate your saw in the starting
throttle position. Engine speed cannot
be controlled with the throttle trigger in
this position.
Work calmly and carefully – in daylight
conditions and only when visibility is
good. Ensure you do not endanger
others – stay alert at all times.
Use the shortest possible guide bar: The
chain, guide bar and chain sprocket
must match each other and your saw.
Position the saw so that your body is
clear of the cutting attachment.
If conditions allow, work from a lift
bucket.
Never work on a ladder or on any other
insecure support, do not work above
shoulder height.
Cordon off the work area in order to
reduce the risk of injuries and damage to
property from falling branches (e.g.
motor vehicles).
When working with a lifeline there is a
risk of cutting through the rope – to
reduce the risk of fall injuries, always
use double lifelines.
Take special care when cutting through
a limb. Hold the machine firmly to control
and counteract the feed force. Note
when reaching the end of a cut that the
saw is no longer supported in the kerf.
You have to take the full weight of the
saw – increased risk of accidents.
10
MS 151 TC
English
001BA248 KN
1
2
3
a
Make sure your saw does not touch any
foreign materials: Stones, nails, etc. may
be flung off and damage the saw chain.
The saw may kick back unexpectedly –
risk of accidents.
If the rotating chain makes contact with
a rock or other solid object there is a risk
of sparking which may cause easily
combustible material to catch fire under
certain circumstances. Dry plants and
scrub are also easily combustible,
especially in hot and dry weather
conditions. If there is a risk of fire, do not
use your chainsaw near combustible
materials, dry plants or scrub. Always
contact your local forest authority for
information on a possible fire risk.
Warning! To avoid risk of
electrocution, take extra
precautions when cutting
near power lines. Have
the power switched off
before starting cutting
work in the immediate
vicinity of power lines.
Do not underbuck freely hanging limbs
because the chain may get pinched and
cause kickback and loss of control.
Take care when cutting scrub and young
trees. The saw chain may catch and
throw thin shoots in your direction.
To reduce the risk of injury, take special
care when cutting shattered wood
because of the risk of injury from slivers
being caught and thrown in your
direction.
After finishing a cut, activate the chain
brake to lock the chain or shut off the
engine before moving the saw to
another position in the tree.
Cutting techniques:
Start the cut with the chain running at full
speed.
Always pull the saw out of the cut with
the chain running.
– Cut straight through thin limbs
– In case of thick limbs, first perform
relieving cut from below (approx. 1/5
of diameter), then buck from above
– Support and secure heavy
branches with ropes.
If the saw gets pinched in the cut:
– Shut off the engine and secure the
saw to the tree – in direction of
trunk.
– Carefully free the saw from the cut,
using another saw if necessary.
Limbs under tension:
N Always start relieving cut (1) at the
compression side (A).
N Make relieving cut (1) and then
perform bucking cut (2) at the
tension side (B) – the saw will
otherwise pinch or kick back.
If not otherwise possible, make the
bucking cut from the bottom upwards
(underbuck) – be wary of pushback.
Cutting Attachment
A cutting attachment consists of the saw
chain, guide bar and chain sprocket.
The cutting attachment that comes
standard is designed to exactly match
the chain saw.
– The pitch (t) of the saw chain (1),
chain sprocket and the nose
sprocket of the Rollomatic guide bar
must match.
– The drive link gauge (2) of the saw
chain (1) must match the groove
width of the guide bar (3).
If non-matching components are used,
the cutting attachment may be damaged
beyond repair after a short period of
operation.
MS 151 TC
11
English
001BA244 KN
3006BA001 KN
1
2011BA050 KN
2
2011BA051 KN
1
2
4
3
2011BA052 KN
Chain Scabbard
Your saw comes standard with a chain
scabbard that matches the cutting
attachment.
If guide bars of different lengths are
mounted to the saw, always use a chain
scabbard of the correct length which
covers the complete guide bar.
The length of the matching guide bars is
marked on the side of the chain
scabbard.
Mounting the Bar and Chain
Disengaging the Chain Brake
N Pull the hand guard towards the
front handle until there is an audible
click – the chain brake is
disengaged.
Removing the chain sprocket cover
Mounting the guide bar
N Turn the screw (1)
counterclockwise until the tensioner
slide (2) butts against the left end of
the housing slot.
N Fit the guide bar over the stud (3)
and engage the peg of the tensioner
slide in the hole (4).
12
Fitting the chain
N Unscrew the nut (1) and remove the
sprocket cover (2).
WARNING
Wear work gloves to protect your hands
from the sharp cutters.
MS 151 TC
N Fit chain around the sprocket (1)
2011BA053 KN
1
2
2011BA054 KN
3006BA028 KN
1
2011BA056 KN
and over the guide bar – the cutting
edges on top of the bar must point to
the bar nose.
N Turn the tensioning screw (2)
clockwise until there is very little
chain sag on the underside of the
bar – and the drive link tangs are
engaged in the bar groove.
N Refit the chain sprocket cover –
the pivot pin on the hand guard must
engage the guard on the engine
housing – and then screw the nut
onto the stud fingertight.
N Go to chapter on "Tensioning the
Saw Chain"
English
Tensioning the Saw Chain
(side chain tensioner)
Retensioning during cutting work:
N Shut off the engine.
N Loosen the nut.
N Hold the bar nose up.
N Use a screwdriver to turn the
tensioning screw (1) clockwise until
the chain fits snugly against the
underside of the bar.
N While still holding the bar nose up,
tighten down the nut firmly.
N Go to "Checking Chain Tension".
A new chain has to be retensioned more
often than one that has been in use for
some time.
N Check chain tension frequently –
see chapter on "Operating
Instructions".
MS 151 TC
13
English
2011BA057 KN
Checking Chain Tension
N Shut off the engine.
N Wear work gloves to protect your
hands.
N The chain must fit snugly against
the underside of the bar and it must
still be possible to pull the chain
along the bar by hand when the
chain brake is released.
N If necessary, retension the chain.
A new chain has to be retensioned more
often than one that has been in use for
some time.
N Check chain tension frequently –
see chapter on "Operating
Instructions".
Fuel
This engine is certified to operate on
unleaded gasoline and with the mix ratio
50:1.
Your engine requires a mixture of highquality premium gasoline and highquality two-stroke air-cooled engine oil.
Use premium branded unleaded
gasoline with a minimum octane rating
of 89 (R+M)/2.
Note: Models equipped with a catalytic
converter require unleaded gasoline. A
few tankfuls of leaded gasoline can
reduce the efficiency of the catalytic
converter by more than 50%.
Fuel with a lower octane rating may
result in preignition (causing "pinging")
which is accompanied by an increase in
engine temperature. This, in turn,
increases the risk of the piston seizure
and damage to the engine.
The chemical composition of the fuel is
also important. Some fuel additives not
only detrimentally affect elastomers
(carburetor diaphragms, oil seals, fuel
lines etc.), but magnesium castings as
well. This could cause running problems
or even damage the engine. For this
reason it is essential that you use only
high-quality fuels!
Fuels with different percentages of
ethanol are being offered. Ethanol can
affect the running behaviour of the
engine and increase the risk of lean
seizure.
Gasoline with an ethanol content of
more than 10% can cause running
problems and major damage in engines
with a manually adjustable carburetor
and should not be used in such engines.
Engines equipped with M-Tronic can be
run on gasoline with an ethanol content
of up to 25% (E25).
Use only STIHL two-stroke engine oil or
equivalent high-quality two-stroke aircooled engine oils for mixing.
We recommend STIHL 50:1 two-stroke
engine oil since it is specially formulated
for use in STIHL engines.
To ensure the maximum performance of
your STIHL engine, use a high quality 2cycle engine oil. To help your engine run
cleaner and reduce harmful carbon
deposits, STIHL recommends using
STIHL HP Ultra 2-cycle engine oil or ask
your dealer for an equivalent fully
synthetic 2-cycle engine oil.
To meet the requirements of EPA and
CARB we recommend to use STIHL HP
Ultra oil.
Do not use BIA or TCW (two-stroke
water cooled) mix oils!
Use only STIHL 50:1 heavy-duty engine
oil
or an equivalent quality two-stroke
engine oil for the fuel mix in models
equipped with a catalytic converter.
Take care when handling gasoline.
Avoid direct contact with the skin and
avoid inhaling fuel vapour.
The canister should be kept tightly
closed in order to avoid any moisture
getting into the mixture.
14
MS 151 TC
English
2011BA010 KN
001BA236 KN
001BA232 KN
001BA234 KN
001BA237 KN
The fuel tank and the canister in which
fuel mix is stored should be cleaned
from time to time.
Fuel mix ratio
Only mix sufficient fuel for a few days
work, not to exceed 30 days of storage.
Store in approved safety fuel-canisters
only. When mixing, pour oil into the
canister first, and then add gasoline.
Examples
Gasoline Oil (STIHL 50:1 or equiva-
lent high-quality oils)
liters liters (ml)
10.02(20)
5 0.10 (100)
10 0.20 (200)
15 0.30 (300)
20 0.40 (400)
25 0.50 (500)
Dispose of empty mixing-oil canisters
only at authorized disposal locations.
Fueling
Preparations
N Before fueling, clean the filler cap
and the area around it to ensure that
no dirt falls into the fuel tank.
N Position the machine so that the
filler cap faces up.
Opening
N Turn the cap counterclockwise
(about a quarter turn).
Marks on tank cap and fuel tank must
line up.
MS 151 TC
N Raise grip to vertical position.
N Remove the tank cap.
Filling Up with Fuel
Take care not to spill fuel while fueling
and do not overfill the tank.
STIHL recommends you use the STIHL
filler nozzle for fuel (special accessory).
N Fill the fuel tank.
15
English
001BA234 KN
001BA233 KN
001BA231 KN
001BA235 KN
001BA241 KN
1
001BA238 KN
001BA239 KN
Closing
Grip must be vertical:
N Fit the cap – marks on tank cap and
fuel tank must line up.
N Press the cap down as far as stop.
N While holding the cap depressed,
turn it clockwise until it engages in
position.
N Fold the grip down.
Tank cap is locked.
If the tank cap cannot be locked in the
fuel tank opening
Bottom of cap is twisted in relation to
top.
N Remove the cap from the fuel tank
and check it from above.
Left: Bottom of cap is twisted –
inner mark (1) in line with
outer mark.
Right: Bottom of cap in correct posi-
tion – inner mark is under the
grip. It is not in line with the
outer mark.
N Place the cap on the opening and
rotate it counterclockwise until it
engages the filler neck.
N Continue rotating the cap
counterclockwise (about a quarter
turn) – this causes the bottom of the
cap to be turned to the correct
position.
N Turn the cap clockwise and lock it in
position – see section on "Closing".
The marks on the tank cap and fuel tank
are then in alignment.
16
MS 151 TC
English
2011BA011 KN
Chain Lubricant Filling Chain Oil Tank
For automatic and reliable lubrication of
the chain and guide bar – use only an
environmentally compatible quality
chain and bar lubricant. Rapidly
biodegradable STIHL BioPlus is
recommended.
NOTICE
Biological chain oil must be resistant to
aging (e.g. STIHL BioPlus), since it will
otherwise quickly turn to resin. This
results in hard deposits that are difficult
to remove, especially in the area of the
chain drive and chain. It may even cause
the oil pump to seize.
The service life of the chain and guide
bar depends on the quality of the
lubricant. It is therefore essential to use
only a specially formulated chain
lubricant.
WARNING
Do not use waste oil. Renewed contact
with waste oil can cause skin cancer.
Moreover, waste oil is environmentally
harmful.
NOTICE
Waste oil does not have the necessary
lubricating properties and is unsuitable
for chain lubrication.
Preparations
N Thoroughly clean the oil filler cap
and the area around it to ensure that
no dirt falls into the tank.
N Position the machine so that the
filler cap faces up.
N Open the filler cap.
Filling up with chain oil
N Refill the chain oil tank every time
you refuel.
Take care not to spill chain oil while
refilling and do not overfill the tank.
STIHL recommends you use the STIHL
filler nozzle for chain oil (special
accessory).
N Closing the Tank Cap
There must still be a small amount of oil
in the oil tank when the fuel tank is
empty.
If the oil level in the tank does not go
down, the reason may be a fault in the oil
supply system: Check chain lubrication,
clean the oilways, contact your dealer
for assistance if necessary STIHL
recommends that you have servicing
and repair work carried out exclusively
by an authorized STIHL servicing
dealer.
MS 151 TC
17
English
142BA069 KN
3006BA003 KN
3006BA001 KN
Checking Chain Lubrication
The saw chain must always throw off a
small amount of oil.
NOTICE
Never operate your saw without chain
lubrication. If the chain runs dry, the
whole cutting attachment will be
irretrievably damaged within a very short
time. Always check chain lubrication and
the oil level in the tank before starting
work.
Every new chain has to be broken in for
about 2 to 3 minutes.
After breaking in the chain, check chain
tension and adjust if necessary – see
"Checking Chain Tension".
Chain Brake
Locking the Chain
– in an emergency
– when starting
– at idling speed
The chain brake is activated by pushing
the hand guard toward the bar nose with
your left hand – or by inertia in certain
kickback situations: The chain is
stopped and locked.
Disengaging the Chain Brake
N Pull the hand guard towards the
front handle until there is an audible
click – the chain brake is
disengaged.
NOTICE
Always disengage chain brake before
accelerating the engine (except when
checking its operation) and before
starting cutting work.
High revs with the chain brake engaged
(chain locked) will quickly damage the
powerhead and chain drive (clutch,
chain brake).
The chain brake is also activated by the
inertia of the front hand guard if the
kickback force of the saw is high
enough: The hand guard is accelerated
toward the bar nose.
The chain brake will operate only if the
hand guard has not been modified in any
way.
Checking Operation of the Chain Brake
Before starting work: Run engine at idle
speed, engage the chain brake (push
hand guard towards bar nose) and open
the throttle wide for no more than
18
MS 151 TC
English
2011BA042 KN
2011BA043 KN
3 seconds – the chain must not rotate.
The hand guard must be free from dirt
and move freely.
Chain Brake Maintenance
The chain brake is subject to normal
wear. It is necessary to have it serviced
and maintained regularly by trained
personnel. STIHL recommends that you
have servicing and repair work carried
out exclusively by an authorized STIHL
servicing dealer. Maintain the following
servicing intervals:
Full-time usage: every 3
months
Part-time usage: every 6
months
Starting / Stopping the
Engine
Positions of Master Control Lever
Stop 0 – engine off – the ignition is
switched off
Normal run position (F) – engine runs or
can fire.
Starting throttle n – for starting the
engine
Positions of Choke Shutter
Choke shutter closed l – for starting
the engine
Select this position:
– if the engine is cold
– if the engine stalls when you open
the throttle after starting.
– if the fuel tank was run until empty
(engine stopped).
Choke shutter open j – for starting the
engine
Select this position:
– if the engine is warm, i.e. if it has
been running for about one minute.
– after engine begins to fire,
– after clearing a flooded combustion
chamber.
MS 151 TC
Setting the Master Control Lever
To move the Master Control lever from
the normal run position (F) to starting
throttle (n), press down the throttle
trigger lockout and squeeze the throttle
trigger at the same time and hold them in
that position – now set the Master
Control lever.
19
English
3006BA026 KN
2011BA014 KN
The Master Control lever moves from
the starting throttle position (n) to the
run position (F) when you press down
the throttle trigger lockout and blip the
throttle trigger at the same time.
To switch off the engine, move the
Master Control lever to Stop (0).
Manual fuel pump
The manual fuel pump bulb must be
pressed:
– When starting for the first time.
– if the fuel tank was run until empty
(engine stopped).
Holding the Saw
N Place your saw on the ground.
Make sure you have a firm footing –
check that the chain is not touching
any object or the ground.
N Hold the saw firmly with your right
hand on the top handle.
N Rest your right knee on the
carburetor box cover.
starter grip snap back. Guide it
slowly back into the housing so that
the starter rope can rewind properly.
Starting the Saw
WARNING
Bystanders must be well clear of the
general work area of the saw.
N Press the manual fuel pump bulb at
least nine times – even if the bulb is
already filled with fuel.
20
Cranking
N Pull the starter grip slowly with your
left hand until you feel it engage –
and then give it a brisk strong pull
and push down the control handle at
the same time. Do not pull out the
starter rope to full length – it might
otherwise break. Do not let the
MS 151 TC
English
4
1
3006BA007 KN
2
3
3006BA021 KN
3006BA022 KN
3006BA022 KN
4
3006BA008 KN
3
3006BA001 KN
N Push the hand guard (1) forward –
the chain is locked.
N Press down the trigger lockout (2)
and pull the throttle trigger (3) at the
same time. Set Master Control
lever (4) to starting throttle
position (n).
N Set choke lever to required position.
Choke shutter closed (l)
Choke shutter open (j)
– if the engine is warm, i.e. if it has
been running for about one minute.
N Hold and start your saw as
described.
When engine begins to fire
N Move the choke lever to the open
position (j).
N Hold and start your saw as
described.
As soon as the engine runs
N Press down trigger lockout and the
blip the throttle trigger (3) – the
Master Control lever (4) moves to
the run position (F) and the engine
settles down to idling speed.
– if the engine is cold (also use this
position if the engine stopped when
you opened the throttle after
starting)
MS 151 TC
N Pull the hand guard toward the
control handle to disengage the
chain brake.
21
English
NOTICE
Always disengage chain brake before
accelerating the engine. High revs with
the chain brake engaged (chain locked)
will quickly damage the clutch and chain
brake.
N After a cold start, warm up the
engine at varying speeds – your saw
is ready for operation.
At very low outside temperatures
If idling behavior is erratic or
acceleration is poor:
N Readjust carburetor if necessary,
see "Adjusting the Carburetor".
N If your saw is very cold (frost or ice
on machine), start the engine and
keep it at a high idle speed (with
chain brake disengaged) until it
reaches normal operating
temperature.
Stopping the engine
N Move Master Control lever to
Stop 0.
If engine does not start
If you did not move the Master Control
lever from the choke closed
position (l) to the choke open
position (j) quickly enough after the
engine began to fire, the engine is
probably flooded.
N Move Master Control lever to
Stop 0.
N Remove the spark plug – see
"Spark Plug".
N Dry the spark plug.
N Crank the engine several times with
the starter to clear the combustion
chamber.
N Refit the spark plug – see "Spark
Plug".
N Set Master Control lever to the
starting throttle position (n) – even
if the engine is cold.
N Now start the engine.
If fuel tank has been run completely dry
and then refueled
N Press manual fuel pump bulb at
least nine times.
N Set the Master Control lever to the
starting throttle position (n).
N Move the choke lever to the closed
position (l)
N Give the starter rope two pulls.
N Move the choke lever to the open
position (j).
N Now start the engine.
Operating Instructions
During the break-in period
A factory new machine should not be run
at high revs (full throttle off load) for the
first three tank fillings. This avoids
unnecessarily high loads during the
break-in period. As all moving parts
have to bed in during the break-in
period, the frictional resistances in the
shortblock are greater during this period.
The engine develops its maximum
power after about 5 to 15 tank fillings.
During work
NOTICE
Do not make the mixture leaner to
achieve an apparent increase in power –
this could damage the engine – see
"Adjusting the Carburetor".
NOTICE
Open the throttle only when the chain
brake is off. Running the engine at high
revs with the chain brake engaged
(chain locked) will quickly damage the
shortblock and chain drive (clutch, chain
brake).
Check chain tension frequently
A new saw chain must be retensioned
more frequently than one that has been
in use already for an extended period.
22
MS 151 TC
English
2
3
1
143BA026 KN
Chain cold
Tension is correct when the chain fits
snugly against the underside of the bar
but can still be pulled along the bar by
hand. Retension if necessary – see
"Tensioning the Saw Chain".
Chain at operating temperature
The chain stretches and begins to sag.
The drive links must not come out of the
bar groove on the underside of the bar –
the chain may otherwise jump off the
bar. Retension the chain – see
"Tensioning the Saw Chain".
NOTICE
The chain contracts as it cools down. If it
is not slackened off, it can damage the
crankshaft and bearings.
After a long period of full-throttle
operation
After a long period of full-throttle
operation, allow engine to run for a while
at idle speed so that the heat in the
engine can be dissipated by flow of
cooling air. This protects enginemounted components (ignition,
carburetor) from thermal overload.
After finishing work
N Slacken off the chain if you have
retensioned it at operating
temperature during work.
NOTICE
Always slacken off the chain again after
finishing work. The chain contracts as it
cools down. If it is not slackened off, it
can damage the crankshaft and
bearings.
Short-term storage
Wait for engine to cool down. Keep the
machine with a full tank of fuel in a dry
place, well away from sources of
ignition, until you need it again.
Long-term storage
See "Storing the machine"
Taking Care of the Guide Bar
N Flip the bar – after each sharpening
and each time the chain is changed
– to avoid uneven wear, especially
at the sprocket nose and on the
bottom
N Periodically clean the oil inlet
hole (1), oil outlet channel (2) and
bar groove (3)
N Measure groove depth – using the
measuring tool on the file gauge
(special accessory) – in the area
with the greatest wear
Chain type Chain pitch Minimum
groove depth
Picco 1/4“ P 4.0 mm
Rapid 1/4“ 4.0 mm
MS 151 TC
23
English
3006BA009 KN
3009BA010 KN
Picco 3/8“ P 5.0 mm
Rapid 3/8“; 0.325“ 6.0 mm
Rapid 0.404“ 7.0 mm
If the groove is not at least this deep:
N Replace guide bar
Otherwise the drive links will grind
against the base of the groove – the
bottoms of the cutters and the tie straps
will not lie against the bar.
Cleaning the Air Filter
If there is a noticeable loss of engine
power
N Turn the twist lock 90°
counterclockwise.
N Remove the shroud upwards.
Engine Management
Exhaust emissions are controlled by the
design of the engine and components
(e.g. carburation, ignition, timing and
valve or port timing).
24
N Remove the air filter upwards.
N Wash the filter in STIHL special
cleaner (special accessory) or a
clean, non-flammable solution (e.g.
warm soapy water) and then dry.
NOTICE
Do not use a brush to clean the filter.
Always replace a damaged filter.
MS 151 TC
English
L
H
3006BA011 KN
3006BA025 KN
Adjusting the Carburetor
General Information
The carburetor comes from the factory
with a standard setting.
This setting provides an optimum fuel-air
mixture under most operating
conditions.
Preparations
N Shut off the engine.
N Check the air filter and clean or
replace if necessary.
N Check the spark arresting screen
(not in all models, country-specific)
in the muffler and clean or replace if
necessary.
Standard Setting
Adjusting Idle Speed
N Carry out the standard setting.
N Start the engine.
Warm up the engine. Allow engine to
idle for 10 seconds before adjusting the
idle speed.
Engine stops while idling
N Turn the idle speed screw (LA)
clockwise until the chain begins to
run – then back it off 4 turns.
Saw chain runs while engine is idling
N Turn the idle speed screw (LA)
counterclockwise until the chain
stops moving – allow engine to run
at idle speed for 10 seconds.
N Turn the idle speed screw (LA)
clockwise until the chain begins to
run – then back it off 4 turns.
N Turn the low speed screw (L)
carefully counterclockwise, no
further than stop, until the engine
runs smoothly and accelerates well.
It is usually necessary to change the
setting of the idle speed screw (LA) after
every correction to the low speed
screw (L).
Fine Tuning for Operation at High
Altitude
A slight correction of the setting may be
necessary if the engine does not run
satisfactorily:
N Carry out the standard setting.
N Warm up the engine.
N Turn high speed screw (H) slightly
clockwise (leaner) – no further than
stop.
NOTICE
After returning from high altitude, reset
the carburetor to the standard setting.
If the setting is too lean there is a risk of
engine damage due to insufficient
lubrication and overheating.
N Turn high speed screw (H)
counterclockwise as far as stop (no
more than 3/4 turn).
N Turn the low speed screw (L)
clockwise as far as stop, then turn it
back 1/4 turn.
MS 151 TC
WARNING
If the chain continues moving when the
engine is idling, have your saw checked
and repaired by your servicing dealer.
Erratic idling behavior, poor acceleration
(even though standard setting of low
speed screw is correct)
Idle setting is too lean
25
English
3006BA001 KN
1
2011BA050 KN
2
2011BA029 KN
000BA039 KN
A
1
000BA045 KN
Spark Plug
N If the engine is down on power,
difficult to start or runs poorly at idle
speed, first check the spark plug.
N Fit a new spark plug after about 100
operating hours – or sooner if the
electrodes are badly eroded. Install
only suppressed spark plugs of the
type approved by STIHL – see
"Specifications".
Removing the Spark Plug
N Move the Master Control lever to 0
or STOP.
N Disengaging the Chain Brake
N Pull off the spark plug boot.
N Unscrew the spark plug.
Checking the Spark Plug
N Clean dirty spark plug.
N Check electrode gap (A) and
readjust if necessary – see
"Specifications".
N Rectify the problems which have
caused fouling of the spark plug.
Possible causes are:
– Too much oil in fuel mix.
– Dirty air filter.
– Unfavorable running conditions.
WARNING
Arcing may occur if the adapter nut (1) is
loose or missing. Working in an easily
combustible or explosive atmosphere
may cause a fire or an explosion. This
can result result in serious injuries or
damage to property.
N Use resistor type spark plugs with a
properly tightened adapter nut.
Installing the spark plug
N Install the spark plug and connect
the spark plug boot (press it down
firmly) – reassembly all other parts
in the reverse sequence.
N Unscrew the nut (1) and remove the
sprocket cover (2).
26
MS 151 TC
English
2011BA045 KN
2
3006BA015 KN
3006BA016 KN
3
Storing the Machine Checking and Replacing the
Chain Sprocket
For periods of 3 months or longer
N Drain and clean the fuel tank in a
well ventilated area.
N Dispose of fuel properly in
accordance with local
environmental requirements.
N Run the engine until the carburetor
is dry – this helps prevent the
carburetor diaphragms sticking
together.
N Remove the saw chain and guide
bar, clean them and spray with
corrosion inhibiting oil.
N Thoroughly clean the machine – pay
special attention to the cylinder fins
and air filter.
N If you use a biological chain and bar
lubricant, e.g. STIHL BioPlus,
completely fill the chain oil tank.
N Store the machine in a dry, high or
locked location, out of the reach of
children and other unauthorized
persons.
N Disengage the chain brake: Pull the
hand guard toward the front handle.
N Remove the chain sprocket cover,
chain and guide bar.
Replace the chain sprocket
A locking strip is required to block the
piston in the cylinder when the chain
sprocket and clutch are removed and
installed as described below. The
locking strip is supplied as standard with
the replacement sprocket.
STIHL recommends the use of original
STIHL sprockets to ensure correct
operation of the chain brake.
Removing
N Remove the spark plug boot (1).
N Unscrew the spark plug (2).
N Turn the clutch until the piston is
about bottom dead center.
MS 151 TC
– after using two saw chains or
sooner
– if the wear marks (arrows) on the
sprocket are deeper than approx.
0.5 mm since this would reduce the
life of the chain. You can use a
gauge (special accessory) to check
the depth of the wear marks.
It is best to use two saw chains in
rotation with one sprocket.
N Insert the locking strip (3) into the
cylinder through the spark plug
hole.
N Turn the clutch clockwise until the
piston butts against the locking
strip.
27
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