MAINTENANCE

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 service agent, 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.

High speed jet H

The high speed jet H influences the power and engine speed of the machine. If the high speed jet is set too rich (H-jet screwed in too far) the machine will over-rev and this will damage the engine. Run the machine at full throttle for about 10 seconds. Then turn the H-jet 1/4 turn anti- clockwise. Run the machine at full throttle for another 10 seconds or so and listen to the difference in the fast idle speed. Repeat this procedure with the H-jet turned a further 1/4 turn anti-clockwise.

H

You have now run the machine at settings of H =± 0, H=+1/ 4, H=+1/2 relative to the basic settings. At full throttle the engine has sounded different for each setting. The H-jet is correctly adjusted when the machine burbles a little. If the machine ”screams” then the machine is set too lean. If the muffler emits a lot of smoke and the machine burbles a lot then the setting is too rich. Turn the H-jet clockwise until the setting sounds right

CAUTION! To ensure correct adjustment you should enlist a qualified mechanic who has access to a tachometer. The recommended maximum fast idle speed must not be exceeded.

Correctly adjusted carburettor

When the carburettor is correctly adjusted the machine accelerates without hesitation and burbles 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. If the L and H-jets are set too rich it will lead to acceleration problems or too low a working speed.

Starter

WARNING! When the recoil spring is wound

!up in the starter housing it is under tension and can, if handled carelessly, pop out and cause personal injury. Always be careful when changing the recoil spring or the starter cord. Always wear protective goggles.

Changing a broken or worn starter cord

Loosen the screws that hold the starter against the crankcase and remove the starter.

Pull out the cord approx. 30 cm and hook it into the notch in the rim of the pulley. Release the recoil spring by letting the pulley rotate slowly backwards.

Undo the screw in the centre of the pulley and remove the pulley. Insert and fasten a new starter cord to the pulley. Wind approx. 3 turns of the starter cord onto the pulley.

Connect the pulley to the recoil spring so that the end of the spring engages in the pulley. Fit the screw in the centre of the pulley. Insert the starter cord through the hole in the starter housing and the starter handle. Make a secure knot in the end of the starter cord.

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Jonsered CS 2147 manual Starter, Fine adjustment of the idle speed T, High speed jet H, Correctly adjusted carburettor