Husqvarna How to Adjust Idle and Carburetor on Chainsaws: Tips and Settings
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MAINTENANCE

General

The user must only carry out the maintenance and service work described in this manual.

IMPORTANT! Any maintenance other than that described in this manual must be carried out by your servicing dealer (retailer).

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

TH

L

•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 the T-screw must be turned anti-clockwise until the chain stops.

Rec. idle speed: 2700 rpm

WARNING! Contact your servicing dealer, if

!the idle speed setting cannot be adjusted so that the chain stops. 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 the T-screw must be turned anti-clockwise until the chain stops.

Fine adjustment of the idling speed T

Adjust the idle speed with the T-screw. If it is necessary to re- adjust, turn the T-screw clockwise while the engine is running, until the chain starts to rotate. Then turn counter-clockwise until the chain 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 chain starts to rotate.

WARNING! Contact your servicing dealer, if

!the idle speed setting cannot be adjusted so that the chain stops. Do not use the chain saw until it has been properly adjusted or repaired.

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Contents 385XP 390XP Symbols on the machine KEY to SymbolsSymbols in the operator’s manual You will find the following labels on your chain sawContents Dear customer IntroductionWhat is what on the chain saw? What is WHAT?Always use common sense General Safety PrecautionsBefore using a new chain saw Chain brake and front hand guard Machine′s safety equipmentPersonal protective equipment General Safety Precautions Right hand guard Throttle lockChain catcher Cutting equipment Stop switchVibration damping system MufflerCutting equipment designed to reduce kickback General rulesBar ChainGeneral information on sharpening cutting teeth Sharpening your chain and adjusting depth gauge settingSharpening cutting teeth Instructions considerably increases the risk of kickbackAdjustment of depth gauge setting General advice on adjusting depth gauge settingIf the depth gauge setting is too large Tensioning the chainChain oil Lubricating cutting equipmentFilling with chain oil Checking chain lubricationChecking wear on cutting equipment Chain drive sprocketNeedle bearing lubrication Fitting the bar and chain AssemblyFuel Fuel HandlingFueling Fuel safetyTransport and storage Long-term storageStarting and stopping Starting and StoppingCold engine Warm engineStopping Working Techniques Basic safety rulesBefore use General working instructionsGeneral rules Terms Basic cutting techniqueGeneral Cutting LimbingSafe distance Tree felling techniqueFelling direction Clearing the trunk and preparing your retreatFelling cut FellingDirectional cuts Freeing a tree that has fallen badly General adviceFreeing a trapped tree Cutting trees and branches that are in tensionCutting the trunk into logs How to avoid kickbackWhat is kickback? General MaintenanceCarburetor adjustment High speed jet H Correctly adjusted carburetorChecking brake band wear Checking the front hand guardChecking the brake trigger Changing a broken or worn starter cord MufflerStarter Tensioning the recoil spring Air filterChanging a broken recoil spring Fitting the starterWhen making adjustments Adjustment of the oil pumpSpark plug Lubricating the bar tip sprocketCooling system Air Injection centrifugal cleaningWinter use Heated handlesDaily maintenance Weekly maintenance Monthly maintenance Maintenance scheduleTechnical data Technical Data058/1,5 mm Saw chain filing and file gauges050/1,3 mm Your Warranty Rights and Obligations Federal Emission Control Warranty StatementSafety precautions for chain saw users American Standard Safety PrecautionsKickback safety precautions Other safety precautionsPage ´z+R1=¶5¨ Page 1150172-95 ´z+R1=¶5¨ ´z+R1=¶5¨
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