Husqvarna 340, 345, 346XP,350, 351, 353 manual Carburettor pressure testing, Carburettor refitting

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Repair instructions

Carburettor – pressure testing

Pressure testing should be carried out with the carburettor fully assembled. Testing should always be carried out after the carburettor has been repaired, but can also be performed for trouble- shooting before dismantling.

Carry out the test as follows:

•Screw in the high and low speed jet screws and back them off one turn.

•Connect pressure tester 502 50 38-01 to the carburettor fuel inlet.

•Lower the carburettor into a beaker of water.

•Pump up the pressure to 50 kPa (0.5 bar) and clamp the pump tube.

•There should be no leakage. If leakage occurs, refer to the table below.

Leakage

Fault lies in

 

 

Diffuser jets

Needle valve

In impulse tube

Pump diaphragm

Ventilation hole above

 

metering unit

Control diaphragm

 

 

Carburettor – refitting

NOTE!

Cleanliness is very important when reas- sembling the carburettor. Tiny particles of dirt can cause operating problems.

1

Fit stop plate 502 54 17-01 between the carburet- tor flange and the insulating plate.

On saws with a carburettor heater 346XPG, 351G, 353G

Insert the heating element between the air filter connection and carburettor as well as above the carburettor. Route the cable as illustrated above.

Tighten the bracket above the carburettor with the two bolts.

Connect the cables to the carburettor heater.

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Contents 340 345 346XP 350 351 Workshop manual Husqvarna 340/345/346XP/350/351/353 Contents Appendix A, Carburettor EPA modelsArrangement of the manual TroubleshootingIntroduction Construction and functionGeneral instructions Safety regulationsSpecial instructions Special tools 20 b 20 c 20 aTechnical data Rpm Construction and function CarburettorConstruction and function Starting TroubleshootingIdling low rpm High rpm Acceleration and retardationRepair instructions Cleaning and inspectionChain brake dismantling Chain brake reassembly Operating testSilencer refitting Chain catcher replacementSilencer removal RefitStop switch removal Stop switch resistance measurementStop switch refitting Choke control removalThrottle lock, throttle trigger and return spring removal Choke control refittingThrottle lock, throttle trigger and return spring refitting Switch troubleshooting Generator 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 cordTensioning the recoil spring Starter assembly refittingReplacing a worn recoil spring Ignition module/flywheel removal Ignition module testingModel 346XP, 351 Replacing the generator, model 346XP, 351 Generator refittingIgnition module and flywheel refitting Centrifugal clutch removal Inspection and cleaningCentrifugal 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 refitting Carburettor pressure testingOn saws with a carburettor heater 346XPG, 351G, 353G Carburettor heater 346XP, 351, 353 Refitting Air intake system removal Air intake system refitting Basic requirements Carburettor adjustmentLow speed jet L Fuel tank removal Fine adjustment of idling speed TCarburettor correct adjustment High speed jet HReplacing the fuel filter Replacing the fuel hoseTank vent testing Fuel tank refittingModels 340 Piston and cylinder removalIf 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 Sealing ring replacement drive side Crankshaft bearings replacement 346XP, 351Sealing ring replacement Crankshaft complete dismantling 340, 345Crankcase and crankshaft reassembly 346XP, 351 Crankshaft bearings 340, 345, 350 replacementTake care to avoid damaging the crank- case Crankshaft complete 340, 345, 350 reassembly Guide bar bolts replacement Repairing damaged threadsThread insert Check that Basic adjustment for EPA II carburetorsReplacement of the L-needle 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.
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