beautypg.com

Carburettor, Idle speed setting – Husqvarna 2101xp User Manual

Page 17

Attention! The text in this document has been recognized automatically. To view the original document, you can use the "Original mode".

background image

Carburettor

WARNING! Do not start the saw without the bar, chain and clutch
cover assembled. If you do, the clutch might come loose and
cause severe injuries.

• In the carburettor, air/fuel is mixed. This air/fuel mixture is

adjustable.

• The carburettor has three adjustment possiblities:

L = Low speed needle

H = High speed needle

T = Idle speed adjustment screw

• When the saw is tested at the factory, the carburettor is adjusted

to a basic setting.

0

• Basic setting;

H=1.0 turn open, L=

1

V

4

turnopen

Local climate and differences in altitude may require an

adjustment.

When working at high altitudes, the H-needle is turned

clockwise, (gives a leaner fuel mixture).

When working at sea level, the H-needle is turned counter­

clockwise, (gives a richer fuel mixture).

NOTE! Small derivations from the basic setting, influence the rpm

of the saw, substantially.

Basic setting of carburettor

Check that the air filter is clean.

Turn the needles H and L carefully in (clockwise).
Then tu rn the needles out to the recommended basic position,

(counter-clockwise) H=1.0 turn open, L=1 Viturn open.

Start the saw and warm it up, according to the starting

instruqiions.

Idle speed setting

If an adjustment is necessary, adjust with theT screw. Adjust the idle

speed so that the chain does not rotate.

Check the function of the saw, if necessary, make a final

adjustment.

Final setting of carburettor

A final setting of the carburettor can only be done after the basic

setting and when the saw is warmed up.

Apart from minor readjustments, you should leave all car­

burettor settings and repair work to your servicing dealer.

Start with the low speed needle L.

Low speed needle L

Apply full throttle a couple of times and check that the saw is
accelerating without hesitation.

If a setting is necessary, try to reach themaximumidle speed, by

slowly closing the low speed needle L clockwise. Then open
(counter-clockwise),

'U

of a turn.

Check the engine acceleration.

NOTE! A too lean adjusted low speed needle (the L-needle closed

too much), results in starting difficulties. After a correct setting of

the L-needle, you may proceed to setting of the H-needle.

High speed needle H

This saw is equipped with a built-in governor. At the maximum

rpm, the governor furnishes the engine with an extra amount of

fuel, which prevents over-reving of the engine. The governor is

set at the factory and cannot be readjusted.

The high speed needle (H) influences the power of the engine

and should be adjusted according to the recommended basic

setting,

1.0

turn out.

CAUTION! A too lean adjusted high speed needle (the H-needle

turned too far clock-wise) lowers the power of the engine and

causes over-heating. This can result in engine damage.

Check with a tachometer that the maximum speed of the

engine does not exceed 10,500 rpm.

Final setting of the idling speed T

Adjust the idling speed with the screw marked T.

Corrections to the setting of the idling speed should be done,

after the H and L adjusting screws are correctly adjusted.

If it is necessary to readjust, first turn the idle speed adjusting

screw (T) clockwise, until the chain starts to rotate. Then turn,
counter-clockwise, until the chain stops.

A correctly adjusted idle speed setting (approx. 2,500 rpm)

occurs when the engine runs smoothly in every position. It should

always be good margin to the rpm when the chain starts to rotate.

CAUTION! Contact your servicing dealer, if the idle speed setting

cannot be adjusted so that the chain stops. Do not use the saw

until it has been properly adjusted or repaired.

17