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.

Functioning, Basic setting, Final setting

!WARNING! Do not start the power cutter without the cutting arm or cutting head fitted. Otherwise the clutch can come loose and cause personal injury.

Operation

The carburetor governs the engine speed via the throttle. Air/ fuel are mixed in the carburetor.

Govenor

The engine is equipped with in the ignition built in non adjustable electronic speed limiter. The limiter prevents the engine from being ran at a too high RPM.

Conditions

Before any adjustments are made the air filters should be clean and the cylinder cowling fitted. Adjusting the carburetor while a dirty air filter 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.

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

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

NOTE! If the blade rotates the T screw should be turned counter-clockwise until the disk stops.

Place the engine on a flat surface so that the disk points away from you and so that the disk do not come into contact with the surface or other objects.

Low speed needle L

Turn the low speed needle L clockwise until the stop. If the engine has bad acceleration or erratic idling, turn the L needle counter-clockwise until good idling and acceleration.

NOTE! If the disk rotates in the idling position, turn the idling speed screw counter-clockwise until the disk stops.

Final setting of the idling speed T

Adjust the idling speed with the screw T. If it is necessary to re- adjust, first turn the idle speed adjusting screw T clockwise, until the disk starts to rotate. Then turn, counter-clockwise until the

The carburetor has three adjustment possibilities:

L = Low speed jet. H = High speed jet.

T = Adjustment screw for idling.

T

H

L

 

disk stops. A correctly adjusted idle speed setting occurs when the engine runs smoothly in every position. It should also be good margin to the rpm when the disk starts to rotate.

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

Correctly adjusted carburetor

A correctly adjusted carburetor means that the engine accelerates without hesitation. Furthermore, the disk must not rotate at idling. A too lean adjusted low speed needle L may cause starting difficulties and bad acceleration. A too lean

The T screw regulates the idling speed. If the screw T is turned clockwise this gives a higher idling speed; counter- clockwise a lower idling speed.

Basic setting and running in

The carburetor is set to its basic setting when test run at the factory. Fine adjustment should be carried out by a skilled technician.

NOTE! If the disk rotates while idling the T screw should be adjusted counter-clockwise until it stops.

Recommended idling speed: 2 500 rpm.

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

adjusted high speed needle H gives lower power=less capacity, bad acceleration and/or damage to the engine. A too rich adjustment of the two speed needles L and H gives accelera- tion problems or too low working speed.

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Husqvarna 371K manual Carburetor