MAINTENANCE

Carburetor

Your Husqvarna product has been designed and manufactured to specifications that reduce harmful emissions.

After your unit has been run 8-10 tanks of fuel the engine has broken in. To ensure that your unit is at peak performance and producing the least amount of harmful emissions after break in, have your authorized servicing dealer, who has a revolution counter at his disposal, to adjust your carburetor for optimum operating conditions.

!WARNING!

The complete clutch cover with shaft must be fitted before the machine is started, otherwise the clutch can become loose and cause personal injury.

Functioning

The carburetor 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 corret.

The setting of the carburetor means that the engine is adjusted to local conditions, for example climate, altitude, gasoline and type of two-stroke oil.

The carburetor has three adjustment possibilities:

L=

Low speed needle

H=

High speed

adjustment screw

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 rpms and a rich one lower rpms.

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 set to its basic setting when test run at the factory. The basic setting should be kept during the machine‘s first working hours. Thereafter the carburetor should be finely adjusted. Fine adjustment should be carried out by a skilled technician.

NOTE! If the cutting attachment rotates/moves in the idling position, turn the idling speed screw counter-clockwise until the blade stops.

Rec. idling speed: 2 700 rpm.

Recommended max. speed: See “Technical Data” .

!WARNING!

Contact your servicing dealer, if the idle speed setting cannot be adjusted so that the cutting attachment stops. Do not use the machine until it has been properly adjusted or repaired.

Fine adjustment

When the machine has been ”run-in” the carburetor should be finely adjusted. The fine adjustment should be carried out by qualified person. First adjust the L-jet, then the idling screw T and then the H-jet.

Conditions

Before any adjustments are made the airfilter should be clean and the airfilter cover fitted. Adjusting the carburetor while a dirty airfilter is in use will result in a leaner mixture when the filter is finally cleaned. This can give rise to serious engine damage.

Carefully turn the L and H needle to the mid point between fully turned in and fully turned out.

Do not attempt to adjust the needles beyond the stops as damage can occur.

Now start the machine according to the starting instructions and run it warm for 10 minutes.

NOTE! If the cutting attachment rotates/moves the T screw should be turned anti-clockwise until the cutting attachment stops.

Low speed needle L

 

 

 

 

 

 

 

 

Try to find the highest idling

 

 

 

 

 

 

 

 

speed, turning the low speed

 

 

 

 

 

 

 

 

needle L clockwise

 

 

 

 

 

 

 

 

respectively counter-

 

 

 

 

 

 

 

 

clockwise. When the highest

 

 

 

 

 

 

 

 

speed has been found, turn

 

 

 

 

 

 

 

 

the low speed needle L 1/4

 

 

 

 

 

 

 

 

turn counter-clockwise.

 

 

 

 

 

 

 

 

NOTE! If the cutting

 

 

 

 

 

 

 

 

attachment rotates/moves in

 

+ 1/4

 

 

 

 

 

 

 

 

 

 

 

the idling position, turn the

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

idling speed screw T

 

 

 

 

 

 

 

 

counter-clockwise until the

 

 

 

 

 

 

 

 

cutting attachment stops.

 

 

 

 

 

 

 

 

 

L

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

24 – English

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Image 24
Husqvarna 325RXT-Series, 323R, 325RX-Series, 325RDX-Series manual Maintenance, Carburetor