Husqvarna 250PS Air filter, Muffler, Spark plug, Correctly adjusted carburettor, Cleaning/change

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MAINTENANCE

Correctly adjusted carburettor

A correctly adjusted carburettor implies that the engine accelerates without a pause and that the engine splutters slightly at full throttle. Also, the chain does not rotate at idling speed. An excessively lean setting for the L-nozzle can result in starting difficulties and poor acceleration. An excessively lean H-nozzle setting results in a lower output, poor acceleration, and/or damage to the engine.

An over rich setting of both L and H results in acceleration problems or excessively low working revs.

Air filter

The air filters must be regularly cleaned from dust and dirt in order to avoid:

Carburettor malfunctions

Starting problems

Engine power reduction

Unnecessary wear on the engine parts

Abnormal fuel consumption

Cleaning/change

Clean the filter after 25 hours or more regularly if operating conditions are exceptionally dusty.

Muffler

The muffler is designed in order to reduce the noise level and to direct the exhaust gases away from the operator. The exhaust gases are hot and can contain sparks, which may cause fire if directed against dry and combustible material.

Some mufflers are equipped with a special screen. If your saw has this type of muffler, you should clean the screen at least once a week. This is done with a wire brush. The screen must be replaced, if damaged. The engine will be overheated, if the screen is clogged. This results in damage on the cylinder and the piston.

CAUTION!

Never use a pruner with a clogged or defective muffler.

Dismantle the air filter cover and remove the air filters. Wash in clean, warm soapy water.

Ensure that the filters are dry before refitting.

An air filter used for a long period of time can never be cleaned completely.

Therefore it is necessary to replace the filter from time to time with a new filter.

A damaged air filter must always be replaced.

Spark plug

The spark plug condition is influenced by:

An incorrect carburettor setting.

An incorrect fuel mixture (too much or faulty oil).

A dirty air filter.

These factors cause deposits on the spark plug electrodes, which may result in malfunction and starting difficulties.

0,5 mm

If the engine is low on power, difficult to start or runs poorly at idling speed, always check the spark plug first.

If the spark plug is dirty, clean it and check the electrode gap. Readjust if necessary. The correct gap is 0.5 mm (.020"). The spark plug should be replaced after about one month or earlier if the electrodes are badly eroded.

IMPORTANT!

Always use the recommended spark plug type. Wrong type may ruin the piston/cylinder.

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Contents 250PS Symbols KEY to SymbolsContents Safety Instructions Machines safety equipmentPersonal protective equipment Vibration damp- ing system SilencerCutting equip- ment Safety Instructions Cutting equipment Cutting equipment designed to minimise kickbackGuide bar Saw chainGeneral information on sharpening cutting teeth Specification of blade and chainSharpening cutting tooth General advice on setting raker clearanceChain lubrication Tensioning the saw chainCorrection of raker clearance CheckingProcedure if the lubrication does not function Checking wear on cutting equipmentSaw chain Chain drive wheel General safety instructions Fuel safetyStart Basic safety precautions General working instructionsTransport and storage Basic clearing techniques What is what? What is WHAT?Adapter AssemblyFuel Handling Fuel mixFuelling Start and stop Fuel Handling Start and StopConnection of the engine unit Start and StopFitting the harness Removing the harnessCarburettor MaintenanceCleaning/change Correctly adjusted carburettorAir filter MufflerCleaning of the shaft Maintenance scheduleAdjustment of the ball joint Daily maintenanceMonthly maintenance Weekly maintenanceTechnical data Technical DataBar Chain Bar and chain combinations´+HÆh¶6v¨ English English2001W14