Jonsered CS2186 Workshop Manual page 38

Adjustment
!
WARNING!
The bar, chain and clutch cover must be
fitted before the chainsaw is started,
otherwise the clutch can work loose and
cause personal injury.
!
WARNING!
Wear ear-muffs
adjustments with the engine running.
Adjusting the carburettor means adapting the engine to local
conditions, e.g. the climate, altitude, petrol and the type of 2-
stroke oil.
The carburettor is fitted with three adjustment possibilities:
L = Low speed jet
H = High speed jet
T = Adjuster screw for idling
The quantity of fuel in relation to the air flow permitted by the
throttle opening is adjusted with the L and H jets. Turning them
clockwise gives a leaner fuel mixture (less fuel) and turning
them anticlockwise gives a richer air/fuel mixture (more fuel).
A lean mixture gives a higher speed, while a rich mixture
gives a lower speed.
The T-screw regulates the position of the throttle while the
engine is idling. Turning the T-screw clockwise gives a higher
idling speed, while turning it anticlockwise gives a lower idling
speed.
Basic settings and running-in
The basic carburettor settings are used for test running in the
factory.
The basic settings are H = 1
respectively.
To ensure that the engine components receive adequate
lubrication (running-in) the carburettor should be set to
a somewhat richer fuel mixture for the first 3-4 hours the
chainsaw is used. To achieve this, the max. overspeed is
adjusted to 6-700 rpm less than the recommended max.
overspeed.
If it is not possible to check the max. overspeed with a
tachometer then the H-jet should not be set to a leaner
mixture than stated in the basic settings.
The recommended max. overspeed must not be exceeded.
NOTE! If the chain goes round at idling speed the T-screw
should be turned anticlockwise until it stops.
Fine adjustment
Fine adjustment of the carburettor should be carried out after
the engine has been "run-in". First adjust the L-jet, then the
idling speed's T-screw, and finally the H-jet.
The following speed recommendations apply:
Max. overspeed
CS2186 13 000 rpm
36 – English
CARBURETTOR
when making
1 1
⁄ and L = 1 ⁄ turns
4 4
Idling speed
2 700 rpm
T
L
Conditions
The air filter should be clean and the cylinder cover fitted
when adjustments are made. Adjusting the carburettor with
a dirty air filter will give a fuel mixture that is too lean the next
time the air filter is cleaned. This can result in serious damage
to the engine.
Carefully screw in (clockwise) the L and H jets until they
bottom. Now screw out (anticlockwise) the jets 1 turn. The
carburettor now has the setting H = 1 and L = 1.
Start the chainsaw according to the starting instructions and
run warm for 10 minutes.
NOTE! If the chain goes round at idling speed
the T-screw should be turned anticlockwise
until it stops.
Place the chainsaw on a flat surface so that the bar points
away from you and so that the chain and bar are not in contact
with the surface or any other object.
H