Husqvarna 340, 345, 346XP,350, 351, 353 Fuel tank removal, Fine adjustment of idling speed T

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Repair instructions

Fine adjustment of idling speed T

•The idling speed is adjusted using the screw marked T.

•If adjustment is necessary, screw in the idling screw T until the chain starts to turn. Then screw it out until the chain stops moving.

•The idling speed is correctly set when the engine runs smoothly in all positions and there is a clear margin to the speed at which the chain starts to move.

High speed jet H

•The high speed jet H influences the saw power output and engine speed. If the H jet is set too weak the saw will over-rev, which could cause engine damage.

•Run the saw at full throttle for about 10 seconds. H=1.

•Then screw out the H screw 1/4 turn. H=1 1/4.

•Run the saw again at full throttle for about 10 seconds and listen to the difference in the engine note. Repeat this procedure again with the H screw screwed out another 1/4 turn. H=1 1/2.

•You have now run the saw at settings H ± 0, H = +1/4 and H = +1/2 from the factory setting. At full throttle the engine will sound different at each setting.

•The H screw is correctly adjusted when the saw “burbles” a little at full throttle without any load.

•If there is a lot of smoke from the silencer and the saw does not run smoothly then the setting is too rich.

•Screw in the H screw to the setting that sounds right.

NOTE!

For optimum adjustment, a tachometer should be used. The recommended maxi- mum speed should not be exceeded.

Carburettor – correct adjustment

•When the carburettor is correctly adjusted the saw should accelerate without hesitation and the engine will burble a little at full throttle without any load.

•The chain must not turn when idling.

•If the L screw is set too weak this can make the saw difficult to start and cause poor acceleration.

•If the H screw is set too weak the saw will produce less power, poor acceleration and there is a risk of engine damage.

•If either the L or H screws are set too rich it will cause acceleration problems or too low working speed.

Fuel tank – removal

WARNING!

The fuel used in chainsaws is harmful if inhaled, may cause skin irritation and is highly flam- mable.

1

Empty the fuel tank.

2

Remove the following:

•cylinder cover

•air filter

•clutch cover

•chain and guide bar

•starter assembly

•cable guide

3

Disconnect the fuel hose from the carburettor.

4

A

C

B

Disconnect the pushrod from the carburettor by first carefully prising up the spring over the end of the rod, where it connects to the throttle lever (A). Then press the throttle lever forwards (B) while pressing the throttle pushrod backwards (C) and lifting it off the lever. Withdraw the throttle pushrod from the tank and lift it upwards without pulling it through the rubber inlet manifold.

38 – English

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Contents 340 345 346XP 350 351 Appendix A, Carburettor EPA models Workshop manual Husqvarna 340/345/346XP/350/351/353 ContentsConstruction and function TroubleshootingIntroduction Arrangement of the manualSafety regulations General instructionsSpecial instructions Special tools 20 a 20 b 20 cTechnical data Rpm Carburettor Construction and functionConstruction and function Troubleshooting StartingIdling low rpm Acceleration and retardation High rpmCleaning and inspection Repair instructionsChain brake dismantling Operating test Chain brake reassemblyRefit Chain catcher replacementSilencer removal Silencer refittingStop switch resistance measurement Stop switch removalChoke control removal Stop switch refittingChoke control refitting Throttle lock, throttle trigger and return spring removalThrottle lock, throttle trigger and return spring refitting Generator troubleshooting Switch troubleshootingHand grip heater on model 346XPG, 351G, 353G removal Troubleshooting carburettor heater 346XPG, 351G, 353G Hand grip heater on model 346XPG, 351G, 353G refitting Heater element and rear hand grip removalReplacing a broken or worn starter cord Starter assembly removalStarter assembly refitting Tensioning the recoil springReplacing a worn recoil spring Ignition module testing Ignition module/flywheel removalModel 346XP, 351 Generator refitting Replacing the generator, model 346XP, 351Ignition module and flywheel refitting Inspection and cleaning Centrifugal clutch removalCentrifugal clutch refitting Model Oil pump removal 346XP, 350, 351Oil pump -refitting 346XP, 350, 351 Oil pump removal 340Oil pump -refitting 340 Carburettor removal Adjustable oil pump adjustment 346XP, 350, 351On saws with a carburettor heater 346XPG, 351G, 353G Carburettor dismantlingCarburettor reassembly Carburettor pressure testing Carburettor refittingOn saws with a carburettor heater 346XPG, 351G, 353G Carburettor heater 346XP, 351, 353 Refitting Air intake system removal Air intake system refitting Carburettor adjustment Basic requirementsLow speed jet L High speed jet H Fine adjustment of idling speed TCarburettor correct adjustment Fuel tank removalReplacing the fuel hose Replacing the fuel filterFuel tank refitting Tank vent testingPiston and cylinder removal Models 340If replacing the cylinder Decompression valve pressure testing Piston and cylinder refitting 346XP, 350, 351 Piston and cylinder refitting 340 Cylinder pressure testingCrankcase and crankshaft dismantling 346XP, 351 Crankshaft complete dismantling 340, 345 Crankshaft bearings replacement 346XP, 351Sealing ring replacement Sealing ring replacement drive sideCrankshaft bearings 340, 345, 350 replacement Crankcase and crankshaft reassembly 346XP, 351Take care to avoid damaging the crank- case Crankshaft complete 340, 345, 350 reassembly Repairing damaged threads Guide bar bolts replacementThread insert H-needle must not rotate Basic adjustment for EPA II carburetorsReplacement of the L-needle Check that114 01 2003W12

340, 345, 346XP,350, 351, 353 specifications

Husqvarna is renowned for its high-quality chainsaws, and the Husqvarna 340, 345, 346XP, 350, 351, and 353 models are no exceptions. These models have garnered a reputation among both professional and amateur users for their reliability, durability, and cutting performance.

The Husqvarna 340 is an entry-level model designed for homeowners and light-duty tasks. It features a 40cc engine that provides a good balance of power and weight, making it easy to handle during extended use. The 340 is equipped with low-vibration technology, significantly reducing operator fatigue and making it suitable for less experienced users.

The Husqvarna 345 is slightly more powerful than the 340, boasting a 45.7cc engine. This model is ideal for users who require a bit more power for medium-duty tasks. It incorporates the air injection system, which helps to separate larger debris before it reaches the air filter, prolonging the life of the filter and maintaining optimal performance.

Moving up the range, the Husqvarna 346XP is a powerful professional chainsaw tailored for demanding tasks. With a 50.2cc engine and the X-Torq engine technology, it provides high cutting performance while reducing fuel consumption and emissions. The 346XP features an adjustable oil pump that allows for precise lubrication, making it an excellent choice for commercial users.

The Husqvarna 350 shares similarities with the 346XP but is designed for users who need a well-rounded saw for various applications. Its 50.2cc engine delivers ample power, and the ergonomically designed handle provides comfort during prolonged use. The chainsaw's advanced starting system ensures easy ignition, even in challenging conditions.

The 351 is another versatile option, equipped with a 50cc engine, designed for both professional and home use. It emphasizes user comfort and ease of handling. The compact design combined with features such as an efficient air filtration system makes the 351 suitable for long hours of work.

Lastly, the Husqvarna 353 is a heavy-duty model that excels in performance and longevity. It has a 50cc engine and incorporates various safety features, including a chain brake and throttle lock, to ensure safe operation. The saw also utilizes the unique anti-vibration system, minimizing vibrations that can lead to user fatigue.

In summary, the Husqvarna 340, 345, 346XP, 350, 351, and 353 models each offer distinct features catering to a wide range of users. From homeowners tackling light tasks to professionals requiring rugged performance, these chainsaws showcase Husqvarna's commitment to quality, innovation, and user-centric design.
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