Husqvarna 1153136-26 manual Maintenance, General, Carburettor adjustment

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MAINTENANCE

General

The user must only carry out the maintenance and service work described in this Operator’s Manual. More extensive work must be carried out by an authorized service workshop.

Carburettor adjustment

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

Function

The carburettor governs the engine’s speed via the throttle control. Air and fuel are mixed in the carburettor. 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 carburettor 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 idle 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 anti- clockwise until the chain stops. When the idle speed is correctly adjusted the engine should run smoothly in every position and the engine speed should be safely below the speed at which 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.

Correctly adjusted carburettor

When the carburettor is correctly adjusted the machine accelerates without hesitation and 4-cycles a little at full throttle. 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 service and repair work on the machine demands special training. This is especially true of the machine’s safety equipment. If your machine fails any of the checks described below we recommend that you take it to your service workshop.

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. (91)

Regularly check that the brake band is at least 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.

Checking the inertia brake release

Place the chain saw, with the engine switched off, on a stump or other stable surface. Release the front handle and let the saw fall by its own weight, rotating around the rear handle towards the stump. (92)

When the bar hits the stump the brake should be applied. (93)

Checking the brake trigger

Place the chain saw on firm ground and start it. Make sure the chain does not touch the ground or any other object. See the instructions under the heading Start and stop.

(94)

Grasp the chain saw firmly, wrapping your fingers and thumbs around the handles. (56)

Apply full throttle and activate the chain brake by tilting your left wrist forward onto the front hand guard. Do not let go of the front handle. The chain should stop

immediately. (52)

26 – English

1153136-26 Rev.1 2009-12-29

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Contents 445 445e 450e English 1153136-26 Rev.1 3839 4243 1153136-26 Rev.1 English 102 Symbols in the operator’s manual KEY to SymbolsSymbols on the machine Decompression valve The valveContents Dear Customer What is what on the chain saw?Introduction General Safety Precautions Before using a new chain sawPersonal protective equipment Machine′s safety equipmentAlways use common sense Chain brake and front hand guardChain catcher Stop switchThrottle lockout Vibration damping systemGeneral rules Sharpening your chain and adjusting depth gauge settingCutting equipment Cutting equipment designed to reduce kickbackTensioning the chain Lubricating cutting equipment Bar 445 AssemblyFitting the bar and chain 445e, 450eFuel Handling FuelTransport and storage Fuel safetyFuelling Long-term storageStarting Starting and StoppingStarting and stopping Cold engineStopping Before use Basic safety rulesWorking Techniques General working instructionsLimbing Basic cutting techniqueTerms Tree felling technique Freeing a tree that has fallen badly How to avoid kickbackWhat is kickback? General MaintenanceCarburettor adjustment Right hand guard MufflerStarter Replacing the starter cordLubricating the bar tip sprocket Air filterSpark plug Needle bearing lubricationCooling system Air Injection centrifugal cleaningTemperature -5C or colder Winter useMaintenance schedule Daily maintenance Weekly maintenance Monthly maintenanceTechnical Data Technical dataBar and chain combinations Saw chain filing and file gaugesEC-declaration of conformity Applies to Europe only EN ISO 12100-22003, Cispr 122005, EN ISOEnglish 1153136-26 Rev.1 1153136-26 Rev.1 English Original instructions 1153136-26