Instruction Manual
Table Of Contents
- STIHL MS 171, 181, 211
- 1 Guide to Using this Manual
- 2 Safety Precautions
- 3 Reactive Forces
- 4 Working Techniques
- 5 Cutting Attachment
- 6 Mounting the Bar and Chain (side chain tensioner)
- 7 Mounting the Bar and Chain (quick chain tensioner)
- 8 Tensioning the Saw Chain (side chain tensioner)
- 9 Tensioning the Saw Chain (quick chain tensioner)
- 10 Checking Chain Tension
- 11 Fuel
- 12 Fueling
- 13 Chain Lubricant
- 14 Filling Chain Oil Tank
- 15 Checking Chain Lubrication
- 16 Chain Brake
- 17 Winter Operation
- 18 Starting / Stopping the Engine
- 18.1 Positions of the master control lever
- 18.2 Adjusting the master control lever
- 18.3 Fuel pump
- 18.4 Holding the chain saw
- 18.5 Starting
- 18.6 Starting the chain saw
- 18.7 When the engine has turned over for the first time
- 18.8 Once the engine is running
- 18.9 At very low temperatures
- 18.10 Switch off the engine
- 18.11 If the engine does not start
- 19 Operating Instructions
- 20 Taking Care of the Guide Bar
- 21 Shroud
- 22 Air Filter System
- 23 Cleaning the Air Filter
- 24 Adjusting the Carburetor
- 25 Spark Arresting Screen in Muffler
- 26 Spark Plug
- 27 Engine Running Behavior
- 28 Storing the Machine
- 29 Checking and Replacing the Chain Sprocket
- 30 Maintaining and Sharpening the Saw Chain
- 31 Maintenance and Care
- 32 Main Parts
- 33 Specifications
- 34 Ordering Spare Parts
- 35 Maintenance and Repairs
- 36 Disposal
- 37 EC Declaration of Conformity
26 Spark Plug
► If the engine is down on power, difficult to start
or runs poorly at idle speed, first check the
spark plug.
► 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 "Specifica‐
tions".
26.1 Removing the spark plug
► Remove the shroud – see "Shroud".
533BA007 KN
► Pull off the spark plug boot.
► Unscrew the spark plug.
26.2 Checking the Spark Plug
000BA039 KN
A
► Clean dirty spark plug.
► Check electrode gap (A) and readjust if neces‐
sary – see "Specifications".
► Rectify the problems which have caused foul‐
ing of the spark plug.
Possible causes are:
–
Too much oil in fuel mix.
–
Dirty air filter.
–
Unfavorable running conditions.
1
000BA045 KN
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 inju‐
ries or damage to property.
► Use resistor type spark plugs with a properly
tightened adapter nut.
26.3 Installing the spark plug
► Install the spark plug and connect the spark
plug boot (press it down firmly) – reassembly
all other parts in the reverse sequence.
27 Engine Running Behavior
If engine running behavior is unsatisfactory even
though the air filter is clean and the carburetor is
properly adjusted, the cause may be the muffler.
Have the muffler checked for contamination (car‐
bonization) by your servicing dealer.
STIHL recommends that you have servicing and
repair work carried out exclusively by an author‐
ized STIHL servicing dealer.
28 Storing the Machine
For periods of 3 months or longer
► Drain and clean the fuel tank in a well ventila‐
ted area.
► Dispose of fuel properly in accordance with
local environmental requirements.
► Run the engine until the carburetor is dry – this
helps prevent the carburetor diaphragms stick‐
ing together.
► Remove the saw chain and guide bar, clean
them and spray with corrosion inhibiting oil.
► Thoroughly clean the machine – pay special
attention to the cylinder fins and air filter.
► If you use a biological chain and bar lubricant,
e.g. STIHL BioPlus, completely fill the chain oil
tank.
English 26 Spark Plug
34 0458-533-8321-E