Husqvarna 327HE4 User Manual

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MAINTENANCE
20 – English
Carburetor
Your Husqvarna product has been designed and 
manufactured to specifications that reduce harmful 
emissions. After the engine has used 8-10 tanks of fuel 
the engine will be run-in. To ensure that it continues to run 
at peak 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 carburettor.
Function
The carburetor governs the engine’s speed via the 
throttle control. Air and fuel are mixed in the 
carburetor. The air/fuel mixture is adjustable. Correct 
adjustment is essential to get the best performance 
from the machine.
The setting of the carburetor means that the engine is 
adapted to local conditions, for example, the climate, 
altitude, fuel and the type of 2-stroke oil.
The carburetor has three adjustment controls:
L = Low speed jet
H = High speed jet
T = Idle adjustment screw
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.
Basic setting
The basic carburetor settings are adjusted during 
testing at the factory. The basic setting is richer than 
the optimal setting and should be maintained for the 
first few hours the machine is in use. The carburettor 
should then be finely adjusted. Fine adjustment 
should be carried out by a skilled technician.
CAUTION!  If the blades move while the engine is idling 
the T screw should be turned anti-clockwise until they 
stop.
Adjustment of the idle speed
Before any adjustments are made, make sure that the air 
filter is clean and the air filter cover is fitted.
Adjust the idle speed with the idle adjustment screw T, if 
adjustment is necessary. First turn the idle adjustment 
screw T clockwise until the blades start to move. Then 
turn the idle adjustment screw T anticlockwise until the 
blades stop. The idle speed is correctly adjusted when the 
engine runs smoothly in every position. There should also 
be a clear margin to the speed at which the blades start 
to move.
 The blades must also remain stationary when the choke 
control is in the start throttle position.
Rec. idle speed: See the Technical data section.
Muffler
CAUTION!  Some mufflers are fitted with a catalytic 
converter. See chapter on Technical data to see whether 
your machine is fitted with a catalytic converter.
The muffler is designed to reduce the noise level and to 
direct the exhaust gases away from the operator. The 
exhaust gases are hot and can contain sparks, which may 
!
WARNING! If the idle speed cannot be 
adjusted so that the cutting attachment 
stops, contact your dealer/service 
workshop. Do not use the machine until 
it has been correctly adjusted or 
repaired.