Husqvarna 440e, 435e manual Maintenance, General, Carburetor adjustment

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MAINTENANCE

General

The user must only carry out the maintenance and service work described in this manual. More extensive work must be carried out by an authorised service workshop.

Carburetor adjustment

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

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 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. Fine adjustment should be carried out by a skilled technician.

Rec. idle speed: See the Technical data section.

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 at idle. Do not use the chain saw until it has been properly adjusted or repaired.

Correctly adjusted carburetor

When the carburetor is correctly adjusted the machine accelerates without hesitation and the machine 4-cycles a little at max. speed. It is also important that the chain does not rotate at idle. If the L-jet is set too lean it may cause starting difficulties and poor acceleration. If the H-jet is set too lean the machine will have less power, poor acceleration and could suffer damage to the engine.

Checking, maintaining and servicing chain saw safety equipment

Note! All servicing and repair work on the machine requires special training. This is especially true of the machines safety equipment. If your machine fails any of the checks described below we recommend you to contact our servicing dealer.

Chain brake and front hand guard

Checking brake band wear

Brush off any wood dust, resin and dirt from the chain brake and clutch drum. Dirt and wear can impair operation of the brake.

Regularly check that the brake band is at least 0.024 inch (0.6 mm) thick at its thinnest point.

Checking the front hand guard

Make sure the front hand guard is not damaged and that there are no visible defects such as cracks.

Move the front hand guard forwards and back to make sure it moves freely and that it is securely anchored to the clutch cover.

115 10 81-95 Rev.1 2008-01-08

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Contents 445 445e 450e You will find the following labels on your chain saw KEY to SymbolsSymbols on the machine Symbols in the operator’s manualContents Dear customer IntroductionWhat is what on the chain saw? What is WHAT?Before using a new chain saw General Safety PrecautionsChain brake and front hand guard Machine′s safety equipmentAlways use common sense Personal protective equipmentGeneral Safety Precautions Chain catcher Throttle lockoutMuffler Stop switchRight hand guard Vibration damping systemBar Cutting equipmentGeneral rules Cutting equipment designed to reduce kickbackGeneral information on sharpening cutting teeth Sharpening your chain and adjusting depth gauge settingToo large General advice on adjusting depth gauge settingIncreased if the depth gauge setting is Adjustment of depth gauge setting445e, 450e Tensioning the chainBar and cause serious or even fatal injury 445Filling with chain oil Lubricating cutting equipmentChecking chain lubrication Needle bearing lubrication Chain drive sprocketChecking wear on cutting equipment 445e, 450e AssemblyFitting the bar and chain 445115 10 81-95 Rev.1 Fuel Fuel HandlingLong-term storage Fuel safetyFueling Transport and storageStarting and stopping Starting and StoppingStarting Stopping General working instructions Basic safety rulesWorking Techniques Before useGeneral rules Terms Basic cutting techniqueSafe distance Tree felling techniqueLimbing Log is supported at one end. There is a high riskClearing the trunk and preparing your retreat Felling directionDirectional cuts Felling cut What is kickback? How to avoid kickbackFreeing a tree that has fallen badly Cutting the trunk into logs Carburetor adjustment MaintenanceGeneral Checking the inertia brake release Muffler Replacing the starter cord StarterTensioning the recoil spring Recoil spring a Air filterReplacing the return and drive springs Fitting the starterCooling system Spark plugLubricating the bar tip sprocket Needle bearing lubricationTemperature -5C 23F or colder Air Injection centrifugal cleaningWinter use Daily maintenance Weekly maintenance Monthly maintenance Maintenance scheduleTechnical data Technical Data058/1,5 mm Bar and chain combinationsSaw chain filing and file gauges 050/1,3 mmYour Warranty Rights and Obligations Federal Emission Control Warranty StatementKickback safety precautions American Standard Safety PrecautionsSafety precautions for chain saw Other safety precautionsPage 1151081-95