Jonsered CS 2171WH Manual De Usuario

English

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The carburettor can be designed in different ways, depending 
on existing environmental and emissions legislation. Some 
chain saws are equipped with movement limiters on the 
carburettor’s adjuster screws. These limit the adjustment 
possibilities to a maximum of a 1/2 turn.

When your chain saw is equipped with a carburettor that 
features movement limiters, the carburettor should be 
adjusted according to the instructions under the heading 
Carburettor with movement limiters.

When your chain saw is equipped with a carburettor that does 
not feature movement limiters, the carburettor should be 
adjusted according to the instructions under the heading 
Carburettor without movement limiters.

Your Jonsered product has been designed and manufactured 
to specifications that reduce harmful exhaust fumes.

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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.

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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.

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The carburettor has three adjustment controls: 

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L = Low speed jet

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H = High speed jet

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T = Idle adjustment screw

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The L and H-jets are used to adjust the supply of fuel to 
match the rate that air is admitted, which is controlled with 
the throttle. If they are screwed clockwise the air/fuel ratio 
becomes leaner (less fuel) and if they are turned anti-
clockwise the ratio becomes richer (more fuel). A lean 
mixture gives a higher engine speed and a rich mixture 
gives a lower engine speed.

•

The T-screw regulates the throttle setting at idle speed. If 
the T-screw is turned clockwise this gives a higher idle 
speed; turning it anti-clockwise gives a lower idle speed.

The basic carburettor settings are adjusted during testing at 
the factory. Avoid running at a too high speed during the first 
10 hours.

CAUTION!  If the chain rotates while idling the T-screw 
must be turned anti-clockwise until the chain stops.

Rec. idle speed: 2700 rpm

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.

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.

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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.

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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.