Instruction Manual

► Turn the low speed screw (L) counterclock‐
wise until the engine runs and accelerates
smoothly.
It is usually necessary to change the setting of
the idle speed screw (LA) after every correction
to the low speed screw (L).
21.7 Fine Tuning for Operation at
High Altitude
A slight correction of the setting may be neces‐
sary if the engine does not run satisfactorily:
► Carry out standard setting.
► Warm up the engine.
► Turn high speed screw (H) slightly clockwise
(leaner) – no further than stop.
NOTICE
After returning from high altitude, reset the car‐
buretor to the standard setting.
If the setting is too lean there is a risk of engine
damage due to insufficient lubrication and over‐
heating.
22 Spark Arresting Screen in
Muffler
WARNING
To reduce the risk of fire caused by hot particles
escaping from the machine, never operate the
machine without a spark arresting screen, or with
the spark arresting screen damaged. Do not
modify the muffler or spark arresting screen. To
reduce the risk of fire from accumulated debris
such as pine needles, branches or leaves,
ensure that the muffler plugs are in place before
taking up work.
NOTICE
According to the law or regulations in some
countries or federal states, certain operations
may only be carried out if a properly serviced
spark arresting screen is provided.
► If the engine is down on power, check the
spark arresting screen in the muffler
► Wait for the muffler to cool down
0001BA009 KN
2
1
► Undo screw (1)
► Pull out the spark arresting screen (2)
► Clean the dirty spark arresting screen, replace
if damaged or heavily carbonized
► Refit the spark arresting screen
► Insert the screw
► If the muffler plugs are missing or damaged,
mount new plugs
23 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".
23.1 Remove the spark plug
► Move the Master Control lever to the stop
position 0
► Push the hand guard forwards – the saw chain
is blocked
1
4903BA002 KN
1
1
2
► Loosen screws (1)
► Remove the shroud (2)
22 Spark Arresting Screen in Muffler English
0458-542-8321-D 29