Husqvarna 41 Chainsaw User Manual


 
Ill!l
Carburetor
I Functioning, Basic setting, Final setting
I
~ WARNING,!DOnot startthe sawwithoutthe bar,chain and clutch
cover (chain brake) assembled. If you do, the clutch might come
loose and cause severe injuries.
1
Functioning
,
The carburett~r governs the engine speed via the throttle
trigger. In the carburetor, air/fuel is mixed. This air/fuel mixture
is adjustable. If you want to take advantage of the maximum
output of the engine, the setting must be correct.
The setting of the carburetor means that the engine is adjusted
to local conditions, for example climate, altitude, petrol and type
of two-stroke oil.
The carburetor has three adjustment possibilities:
L=Low speed needle
H=High speed needle
T=Idle speed adjustment screw
The fuel quantity required in proportion to the airflow the
throttle trigger level allows is adjusted by means of the L- and
H-needles. Turning the needles clockwise gives a leaner fuel
mixture (less fuel), turning them counter-clockwise gives a
richer fuel mixture (more fuel). A lean mixture gives higher
rpm:s and a rich one lower rpm:s.
NOTE: Your unit is equipped with limiter caps, do not attempt
to adjust the needles beyondthe stop as damage can occur.
The idling speed screw T regulates the position of the throttle
lever in the idling speed position. Turn the idling speed screw
clockwise gives a higher idling speed, turn it counter-clockwise
a lower idling speed.
Basic setting
The carburetor is adjusted to a basic setting when the saw is tested
at the factory. The basic setting is richer than the optimum setting
and shall be maintained during the first working hours. Thereafter, do
the final setting of the carburetor. The basic setting can vary
between: H=2-118to 2-7/8 turn respectively L=l-1/2 to 2-1/4 turn.
NOTE! If the chain rotates in the idling position, turn the idling speed
screw counter-clockwise until the chain stops.
Final setting
After the “break in”period(about5 hours),thefinalsettingisto
bedone.
This setting isdonetoensurethatyourunitisrunning
at peak performanceand producingthe least amount of
harmfulemissions.Havethe final aettingdone by quali-
fied servicepersonnel.Thisserviceis notcoveredbywar-
rantv.
First’,adjust the low speed needle
L, then the high speed
needleH, andfinally the idlingspeedscrewT.
The carbure-
tor shouldbe set accordingto the followingRPMlimits:
Max.speed(no Ioad)=l3,000 rpm
Idlingspeed=2800/3200rpm
[
1
Conditions
Before all settings are done the air filter must be clean and the
cylinder cover mounted.
Set the needles marked T, L, and H to the mid point of the
limiter
cap,
Start the saw according to the starting instructions and warm it
up during 10 minutes.
NOTE! if the chain rotates in the idling position, turn the idling
speed screw counter-clockwise until the chain stops.
D Put the saw on a flat surface, the bar pointing in the opposite
direction of you. Avoid that bar and chain get into contact with
the surface or other objects.
, J4
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