Jonsered GR 2126D manual Maintenance, Carburettor, Rec. idling speed 2700 rpm

MAINTENANCE

Carburettor

Your JONSERED 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 carburettor 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 carburettor governs

the engine speed via the throttle trigger. In the carburettor, 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 carburettor means that the engine is adjusted to local conditions, for example climate, altitude, petrol and type of two-stroke oil.

•The carburettor has three adjustment possibilities:

L=	Low speed needle
H=	High speed
adjustment screw
T=	Idle speed adjustment

Basic setting

•The carburettor 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 carburettor 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: 2700 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 carburettor 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 carburettor 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.

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.

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 the idling position, turn the idling speed screw T counter-clockwise until the cutting attachment stops.

+ 1/4

L

22 – English