MAINTENANCE

Carburetor adjustment

Due to existing environmental and emissions legislation your chain saw is equipped with movement limiters on the carburetor adjuster screws. These limit the adjustment possibilities to a maximum of a 1/2 turn.

1/2

1/2

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

Function, Basic settings, Fine adjustment

WARNING! Do not start the chain saw

! unless the bar, chain and clutch cover (chain brake) are fitted, otherwise the clutch may come loose and cause personal injury.

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 settings and running in

The basic carburetor settings are adjusted during testing at the factory. Avoid running at a too high speed for extended periods during the first 10 hours.

CAUTION! If the chain rotates while idling theT-screw must be turned anti-clockwise until the chain stops.

Rec. idle speed: 2500 rpm

WARNING! Contact your servicing

! dealer, if the idle speed setting cannot be adjusted so that the chain stops at idle. Do not use the chain saw 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 a qualified person. First adjust the L- jet, then the idling screw T and then the H-jet.

Conditions

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

Do not attempt to adjust the L and H jets beyond either stop as this could cause damage.

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

CAUTION! If the chain rotates while idling the T- screw must be turned anti-clockwise until the chain stops.

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

Low speed jet L

Turn the low speed jet L clockwise until it stops. If the engine accelerates poorly or idles unevenly, turn the low speed jet L anticlockwise until good acceleration and idling are achieved.

CAUTION! If the chain rotates while idling theT-screw must be turned anti-clockwise until the chain stops.

30 – English

Page 30
Image 30
Husqvarna 395XPG, 1153177-95 manual Maintenance, Carburetor adjustment