MAINTENANCE
CAUTION! If the cutting attachment rotates when the engine
Carburettor
is idling the idle adjustment screw T should be turned anti-
Your Husqvarna product has been designed and clockwise until the cutting attachment stops.
manufactured to speciŢcations that reduce harmful 240R, 245R/RX, 250R, 252RX:
emissions. After the engine has used 8-10 tanks of fuel the Rec. idle speed 2700 rpm
engine will be run-in. To ensure that it continues to run at peak
265RX: Rec. idle speed 2250 rpm
performance and to minimise harmful exhaust emissions
after the running-in period, ask your dealer/service workshop
(who will have a rev counter at their disposal) to adjust your WARNING! If the idle speed cannot be
carburettor.!adjusted so that the cutting attachment
stops, contact your dealer/service
workshop. Do not use the machine until it
WARNING! The complete clutch cover and has been correctly adjusted or repaired.
shaft must be Ţtted before the machine is
started, otherwise the clutch can come loose CAUTION! The machine should only be run for short periods !
and cause personal injury.at its highest speed. For optimum adjustment of the
carburettor, contact a qualiŢed dealer/service workshop that
has a revolution counter at their disposal.
Function
Recommended max. speed: See the Technical data section.
During the running-in period (8-10 tanks of fuel) the maximum
speed should be set 600-700 rpm below the recommended
maximum speed (= open the high speed jet H a further 1/8
Y The carburettor governs the engineOs speed via the turn).
throttle control. Air and fuel are mixed in the carburettor.
The air/fuel mixture is adjustable. Correct adjustment is
Conditions
essential to get the best performance from the machine.
Y Before any adjustments are made, make sure that the air
Y Adjusting the carburettor means that the engine is Ţlter is clean and the air Ţlter cover is Ţtted. If you adjust
adapted to local operating conditions, e.g. climate,
the carburettor when the air Ţlter is dirty it will result in a
altitude, petrol and the type of 2-stroke oil.leaner mixture when the Ţlter is Ţnally cleaned. This can
Y The carburettor has three adjustment controls: lead to serious engine damage.
Y Carefully turn both jets, L and H, so that they are midway
L = Low speed jet
between fully screwed in and fully screwed out.
H = High speed jetY Do not attempt to adjust the L and H jets beyond either
T = Idle adjustment screwstop as this could cause damage.
Y Now start the machine according to the starting
instructions and let it warm up for 10 minutes.
CAUTION! If the cutting attachment rotates when the
engine is idling the idle adjustment screw T should be
turned anti-clockwise until the cutting attachment stops.
Low speed jet L
Try to Ţnd the highest idle speed by turning the low speed jet
Y The L and H-jets are used to adjust the supply of fuel to L clockwise then anti-clockwise. When the highest speed has
match the rate that air is admitted, which is controlled with been found, turn the low speed jet L 1/4 turn anti-clockwise.
the throttle. If they are screwed clockwise the air/fuel ratio + 1/4
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.
Y The T-screw regulates the throttle setting at idle speed. If
the T-screw is turned clockwise this gives a higher idle L
speed; turning it anti-clockwise gives a lower idle speed.
Basic settingFine adjustment of the idle speed T
Y The basic carburettor settings are adjusted during testing Adjust the idle speed using the idle adjustment screw T, if it is
at the factory. The basic setting is richer than the optimal necessary to readjust. First turn the idle adjustment screw T
setting and should be maintained for the Ţrst few hours the clockwise until the cutting attachment starts to rotate. Then
machine is in use. The carburettor should then be Ţnely turn the screw anticlockwise until the cutting attachment
adjusted. Fine adjustment should be carried out by a stops. The idle speed is correctly adjusted when the engine
skilled technician. will run smoothly in every position. The idle speed should also
be well below the speed at which the cutting attachment starts
The basic setting can vary between: H = 1 - 1 1/4 turns to rotate.
and L = 1 - 1 1/4 turns.
28 � English |
ACEC
HUSQVARNA
