Husqvarna 340, 345, 346XP,350, 351, 353 manual Carburettor dismantling

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Heating element

Repair instructions

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

Remove the bracket’s two bolts above the carbu- rettor. Disconnect the cable connections to the carburettor heater and remove the heating ele- ment.

O

 

O

Z

 

N

 

Z

5

 

 

 

 

5

N

 

 

F

 

 

G

 

 

3

 

F

 

G

 

3

 

 

 

K V

 

 

 

X

 

KV

 

X

4

4

Y

1

 

Y

1

H

 

 

H

When replacing the thermostat: Disconnect the cable from X and V. Trouble shooting, see page 20.

On saws with carburettor 346XPG, 351G, 353G Replacing the heating element: Lower the rear section of the tank by removing the bolt between the hand grip cover and vibration damping springs. Remove the starter and then loosen the stop screws on both sides (one is located under the starter and this must be removed first). Now disconnect the cable from X and Y.

Dismantling the carburettor: Loosen the high, low and idling jet screws.

Carburettor – dismantling

The item numbers in the diagram refer to the steps below (1–7).

1

Remove the cover from the metering unit and carefully remove the metering diaphragm and gasket.

2

Undo the screw and take out the needle valve, together with the lever arm, spindle and spring.

3

Remove the cover from the pump unit and carefully remove the gasket and pump diaphragm.

4

Remove the fuel filter.

5

Remove the high, low and idling jet screws. (HDA 159A high and low jet screws are protected by plastic caps which can be prised off with a screw- driver. Only on EPA, see appendix A.)

6

Remove the plug by first drilling a hole in it and then prising it out with a screwdriver or the like.

7

If necessary remove the throttle and choke valves, and remove the spindles together with the lever arms and springs.

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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 functionSpecial instructions Safety regulationsGeneral instructions Special tools 20 b 20 c 20 aTechnical data Rpm Construction and function CarburettorConstruction and function Idling low rpm TroubleshootingStarting High rpm Acceleration and retardationChain brake dismantling Cleaning and inspectionRepair instructions Chain brake reassembly Operating testChain catcher replacement Silencer removalSilencer refitting RefitStop switch removal Stop switch resistance measurementStop switch refitting Choke control removalThrottle lock, throttle trigger and return spring refitting Choke control refittingThrottle lock, throttle trigger and return spring removal Hand grip heater on model 346XPG, 351G, 353G removal Generator troubleshootingSwitch troubleshooting 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 cordReplacing a worn recoil spring Starter assembly refittingTensioning the recoil spring Model 346XP, 351 Ignition module testingIgnition module/flywheel removal Replacing the generator, model 346XP, 351 Generator refittingIgnition module and flywheel refitting Centrifugal clutch refitting Inspection and cleaningCentrifugal clutch removal 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 On saws with a carburettor heater 346XPG, 351G, 353G Carburettor pressure testingCarburettor refitting Carburettor heater 346XP, 351, 353 Refitting Air intake system removal Air intake system refitting Low speed jet L Carburettor adjustmentBasic requirements 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 refittingIf replacing the cylinder Piston and cylinder removalModels 340 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, 345Take care to avoid damaging the crank- case Crankshaft bearings 340, 345, 350 replacementCrankcase and crankshaft reassembly 346XP, 351 Crankshaft complete 340, 345, 350 reassembly Thread insert Repairing damaged threadsGuide bar bolts replacement 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.
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