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30 – English
Fine adjustment
When the machine has been ”run-in” the carburettor
should be finely adjusted. The fine adjustment should be
carried out by a qualified person. First adjust the L-jet,
then the idling screw T and then the H-jet.
Changing the type of fuel
Fine tuning may be required if the chain saw, after
changing the type of fuel, performs differently with regard
to starting, acceleration, maximum speed, etc.
Conditions
• Before any adjustments are made the air filter should
be clean and the cylinder cover fitted. Adjusting the
carburettor while a dirty air filter is in use will result in
a leaner mixture next time the filter is cleaned. This
can give rise to serious engine damage.
• Do not attempt to adjust the L and H jets beyond either
stop as this could cause damage.
• Now start the machine according to the starting
instructions and let it warm up for 10 minutes.
CAUTION! If the chain rotates while idling the T-
screw must be turned anti-clockwise until the
chain stops.
• Place the machine on a flat surface so that the bar
points away from you and so that the bar and chain do
not come into contact with the surface or other
objects.
Low speed jet L
Turn the low speed jet L clockwise until it stops. If the
engine accelerates poorly or idles unevenly, turn the low
speed jet L anticlockwise until good acceleration and
idling are achieved.
CAUTION! If the chain rotates while idling the T-screw
must be turned anti-clockwise until the chain stops.
Fine adjustment of the idle speed T
Adjust the idle speed with the T-screw. If it is necessary to
re-adjust, turn the T-screw clockwise while the engine is
running, until the chain starts to rotate. Then turn anti-
clockwise until the chain stops. When the idle speed is
correctly adjusted the engine should run smoothly in
every position and the engine speed should be safely
below the speed at which the chain starts to rotate.
High speed jet H
At the factory the engine is adjusted at sea level.
When working at a high altitude or in different
weather conditions, temperatures and atmospheric
humidity, it may be necessary to make minor
adjustments to the high speed jet.
CAUTION! If the high speed jet is screwed in too far,
it may damage the piston/cylinder.
When test run at the factory, the high speed jet is set so
that the engine satisfies the applicable legal requirements
at the same time as achieving maximum performance.
The carburettor’s high speed jet is then locked using a
limiter cap in the fully screwed out position. The limiter cap
limits the potential to adjust the high speed jet to at most
half a turn.
CAUTION! There is an integrated speed governor in the
ignition system that limits the maximum speed to 13000
rpm. The maximum speed will not exceed 13000 rpm
when the high speed jet is adjusted (screwed in). When
the speed governor is activated, you will get the same
sound experience as when the chain saw 4-cycles.
To adjust the carburettor correctly you should contact a
mechanic with access to a rev counter.
CAUTION! As the spark is cut off, the rev counter does not
show speeds higher than 13000 rpm.
Correctly adjusted carburettor
When the carburettor is correctly adjusted the machine
accelerates without hesitation and 4-cycles a little at full
throttle. It is also important that the chain does not rotate
at idle. If the L-jet is set too lean it may cause starting
difficulties and poor acceleration. If the H-jet is set too
lean the machine will have less power, poor acceleration
and could suffer damage to the engine.
Carburettor without movement
limiters
Function, Basic settings, Fine adjustment
Function
• The carburettor governs the engine’s speed via the
throttle control. Air and fuel are mixed in the
carburettor. The air/fuel mixture is adjustable. Correct
adjustment is essential to get the best performance
from the machine.
• Adjusting the carburettor means that the engine is
adapted to local operating conditions, e.g. climate,
altitude, petrol and the type of 2-stroke oil.
!
WARNING! Contact your servicing
dealer, if the idle speed setting cannot be
adjusted so that the chain stops. Do not
use the chain saw until it has been
properly adjusted or repaired.
!
WARNING! Do not start the chain saw
unless the bar, chain and clutch cover
(chain brake) are fitted, otherwise the
clutch may come loose and cause
personal injury.
H
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