Husqvarna 340, 345, 346XP,350, 351, 353 manual High rpm, Acceleration and retardation

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Troubleshooting

High rpm

Will not run at

Adjust H screw

full throttle

Blocked air filter

 

Blocked fuel tank vent

 

Blocked fuel filter

 

Fuel line blocked

 

Loose or damaged fuel hose

 

Impulse channel leaking

 

Impulse channel blocked

 

Loose cover on carburettor pump

 

side

 

Faulty pump diaphragm

 

Leaking air intake hose (rubber)

 

Loose carburettor mounting bolts

 

Needle valve set too low

 

Metering system damaged

 

Metering system incorrectly

 

assembled

 

Leaking control diaphragm/cover

 

plate

 

Needle valve assembly sticking

 

Blocked silencer

 

 

Low power

Adjust H screw

 

Blocked fuel tank vent

 

Blocked fuel filter

 

Impulse channel leaking

 

Impulse channel blocked

 

Loose cover on carburettor pump

 

side

 

Faulty pump diaphragm

 

Blocked air filter

 

Needle valve assembly sticking

 

Leak in metering system (air or fuel)

 

Metering system incorrectly

 

assembled

 

Loose diaphragm rivet

 

Hole in diaphragm

 

Leaking control diaphragm/cover

 

plate

 

 

Will not “four-

Blocked fuel tank vent

stroke”

Blocked fuel filter

 

Fuel line blocked

 

Loose or damaged fuel hose

 

Impulse channel leaking

 

Impulse channel blocked

 

Loose cover on carburettor pump

 

side

 

Faulty pump diaphragm

 

Leaking air intake hose (rubber)

 

Loose carburettor mounting bolts

 

Needle valve set too low

 

Leak in metering system (air or fuel)

 

Metering unit incorrectly assembled

 

Loose diaphragm rivet

 

Hole in diaphragm

 

Leaking control diaphragm/cover

 

plate

 

 

Acceleration and retardation

Does not

Adjust L screw

accelerate

Adjust H screw

 

Blocked air filter

 

Blocked fuel tank vent

 

Blocked fuel filter

 

Fuel line blocked

 

Loose or damaged fuel hose

 

Impulse channel blocked

 

Loose cover on carburettor pump

 

side

 

Faulty pump diaphragm

 

Leaking air intake hose (rubber)

 

Loose carburettor mounting bolts

 

Needle valve set too low

 

Metering system incorrectly

 

assembled

 

Needle valve assembly sticking

 

Faulty diffuser jets

 

Blocked silencer

 

 

Engine stalls

Adjust L screw

when throttle

Adjust H screw

released

Faulty pump diaphragm

 

Needle valve set too high

 

Needle valve assembly sticking

 

Faulty diffuser jets

 

 

Over rich

Adjust L screw

acceleration

Adjust H screw

 

Blocked air filter

 

Faulty pump diaphragm

 

Faulty diffuser jets

 

 

Troubleshooting methods

In addition to the faults described in the above table, trouble shooting can be carried out on specific components or sub-systems of the chainsaw. The various procedures are described in the relevant chapters, see the contents page, as follows:

Checking the operation of the chain brake

Measuring the resistance of the stop plate

Pressure testing the carburettor

Pressure testing the decompression valve

Pressure testing the cylinder

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Contents 340 345 346XP 350 351 Workshop manual Husqvarna 340/345/346XP/350/351/353 Contents Appendix A, Carburettor EPA modelsTroubleshooting IntroductionArrangement of the manual Construction and functionSafety regulations General instructionsSpecial instructions Special tools 20 b 20 c 20 aTechnical data Rpm Construction and function CarburettorConstruction and function Troubleshooting StartingIdling low rpm High rpm Acceleration and retardationCleaning and inspection Repair instructionsChain brake dismantling Chain brake reassembly Operating testChain catcher replacement Silencer removalSilencer refitting RefitStop switch removal Stop switch resistance measurementStop switch refitting Choke control removalChoke 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 Heater element and rear hand grip removal Hand grip heater on model 346XPG, 351G, 353G refittingStarter assembly removal Replacing a broken or worn starter cordStarter assembly refitting Tensioning the recoil springReplacing a worn recoil spring Ignition module testing Ignition module/flywheel removalModel 346XP, 351 Replacing the generator, model 346XP, 351 Generator refittingIgnition module and flywheel refitting Inspection and cleaning Centrifugal clutch removalCentrifugal clutch refitting Oil pump removal 346XP, 350, 351 ModelOil pump removal 340 Oil pump -refitting 346XP, 350, 351Oil pump -refitting 340 Adjustable oil pump adjustment 346XP, 350, 351 Carburettor removalCarburettor dismantling On saws with a carburettor heater 346XPG, 351G, 353GCarburettor 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 Fine adjustment of idling speed T Carburettor correct adjustmentFuel tank removal High speed jet HReplacing the fuel filter Replacing the fuel hoseTank vent testing Fuel tank refittingPiston and cylinder removal Models 340If replacing the cylinder Decompression valve pressure testing Piston and cylinder refitting 346XP, 350, 351 Cylinder pressure testing Piston and cylinder refitting 340Crankcase and crankshaft dismantling 346XP, 351 Crankshaft bearings replacement 346XP, 351 Sealing ring replacementSealing ring replacement drive side Crankshaft complete dismantling 340, 345Crankshaft 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 Basic adjustment for EPA II carburetors Replacement of the L-needleCheck that H-needle must not rotate114 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.