MAINTENANCE

Carburetor

Your Jonsered product has been designed and manufactured to specifications that reduce harmful exhaust fumes. The engine will be run in after it has used 8-10 tanks of fuel. To ensure that the engine runs at peak performance and produces as little harmful exhaust fumes as possible after the running-in period, ask your dealer/service workshop (which has a rev counter for this purpose) to adjust your carburettor.

WARNING! The complete clutch cover and

!gear housing must be fitted before the machine is started, 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.

Adjusting the idle 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.

Before any adjustments are made, make sure that the air filter is clean and the air filter cover is fitted.

Adjust the idle speed with the idle adjustment screw T, if adjustment is necessary. First turn the idle adjustment screw T clockwise until the blades start to move. Then turn the idle adjustment screw T anticlockwise until the blades stop. The idle speed is correctly adjusted when the engine runs smoothly in every position. There should also be a clear margin to the speed at which the blades start to move. The blades must also remain stationary when the choke control is in the start throttle position.

T

WARNING! If the idle speed cannot be

!adjusted so that the cutting attachment stops, contact your dealer/service workshop. Do not use the machine until it has been correctly adjusted or repaired.

Muffler

CAUTION! Some mufflers are fitted with a catalytic converter. See chapter on Technical data to see whether your machine is fitted with a catalytic converter.

The muffler is designed 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 spark arrestor screen. If your machine has this type of muffler, you should clean the screen at least once a week. This is best done with a wire brush.

On mufflers without a catalytic converter the screen should be cleaned weekly, or replaced if necessary. On mufflers fitted with a catalytic converter the screen should be checked, and if necessary cleaned, monthly. If the screen is damaged it should be replaced. If the screen is frequently blocked, this can be a sign that the performance of the catalytic converter is impaired. Contact your dealer to inspect the muffler. A blocked screen will cause the machine to overheat and result in damage to the cylinder and piston. See also instructions under the heading Maintenance.

CAUTION! Never use a machine with a defective muffler.

WARNING! Mufflers fitted with catalytic

!converters get very hot during use and remain so for some time after stopping. This also applies at idle speed. Contact can result in burns to the skin. Remember the risk of fire!

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Jonsered HT 2124T manual Maintenance, Carburetor, Muffler, Function, Adjusting the idle speed