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