Husqvarna 343R, 345RX, 343F, 345FX, 345FXT manual Crankshaft and crankcase

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Crankshaft and crankcase

 

 

 

 

 

 

 

The task of the crankshaft is to transform the reciprocating

The crankshaft is journalled in the crankcase on

 

motion of the piston to rotation. This requires a stable

heavy-duty ball bearings. In addition to the journalling

 

design withstanding immense pressure and rotational and

point for the crankshaft, the crankcase acts as a

 

bending strain, as well as high rotational speed. In addition

scavenging pump for the fuel/air mixture when this is

 

the connecting rod is exposed to large acceleration and

“sucked” from the carburettor and is forced into the

 

retardation forces as it moves between the top and bottom

cylinder’s combustion chamber. The crankcase must

 

dead centres. This puts special demands on the bearings

be perfectly sealed so as not to affect this pump

 

that must withstand quick changes in load. Moreover, the

function. There cannot be any leakage from the crank-

 

bearing’s roller retainer must also cope with high tempera-

shaft, between the crankcase halves or between the

 

tures and friction. It is therefore extremely important when

crankcase and the cylinder.

 

servicing to check the roller retainer for cracks, wear and

Always replace the sealing rings and gaskets when

 

discolouration caused by overheating.

servicing the crankcase.

 

 

 

 

 

 

 

 

Dismantling

Dismantle all components so that only the crankcase and crankshaft remain.

Dismantle the guard under the crank- case.

Bend away the heat guard (A) and cable guide (B).

Dismantling

Dismantle all components so that only the crankcase and crankshaft remain.

See the respective sections for detailed information if necessary.

Remove the 4 bolts and lift off the guard from under the crankcase.

Bend away the heat guard (A) with your fingers and carefully push the cable guide (B) aside with a screwdriver.

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Remove the 4 bolts holding the crank- case halves together.

502 50 18-01

Remove the 4 bolts holding the crank- case halves together.

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Contents 343R 345RX 343F 345FX 345FXT Workshop Manual Brushcutter, Trimmer Model 343R, 345RX, 343F, 345FX, 345FXT ContentsGeneral recommendations Starter ContentsDismantling 1StarterStarter AssemblyReplacing the drive dogs Electrical system 502 71 Electrical systemChecking the ignition spark Tip 502 50 Replacing the spark Plug cover502 54 Heated handles Drive dogsWiring diagram Electrical system Fuel system Air filter Fuel systemFuel filter Tank ventingDismantling Fuel pumpCarburettor Blending unit Carburettor’s designMetering unit Dismantling the carburettor Pump unitFuel system Little shorter than the L-needle PositionedFor example, the H-needle is a Assembling the carburettor Than the L-needle H-needle is a little shorterCheck carefully that the fuel hoses Are not bent or pinched whenFine adjustment Carburettor settingsBasic setting Correctly adjusted carburettor Setting Recommended max. speed must not be exceededTachometer should always be used to find the optimal Idling speed T-screwAdjusting the L-needle Adjusting the H Needle Carburettor adjustment 345RX/FX Adjustment 345RX/FXThrottle RotatingCheck for wear on pins a and B Tip Page Centrifugal clutch 502 21 Centrifugal clutchDo not lose the sleeve bearings found in the clutch shoes Centrifugal clutch502 11 Clutch drumChange the bearings in the clutch housing if necessary Page Angle gear Let the small circlip around the axle remain Angle gearInput axle with pinion must be dismantled first 503 97503 80 ShaftCylinder and piston Cylinder and piston Decompression valve Turn the valve the right way when fittingWhen the valve is fitted the small hole must face outwards Inlet manifold Cleaning, inspectionCause Action Analysis and actionsInsufficient lubrication Piston scoring caused by heavy carbon deposits Piston ring breakage Piston damage caused by a too high engine speedCause Foreign objectsDefect Action Service tipsWear tolerances Crankshaft and crankcase Crankshaft and crankcase 502 52 Crankshaft and crankcaseInspecting Crankshaft Assembly Press down the sealing plates as Leakage testing CrankcaseFar as possible between the bolts To ensure a proper seal503 55 Husqvarna E-TechPage Tools List of tools 503 97 502 50 505 38 502 50 502 52503 80 502 50 503 84 503 55114 01 2003W24

343R, 345RX, 343F, 345FX, 345FXT specifications

The Husqvarna 343R, 345RX, 343F, 345FX, and 345FXT are designed for efficiency and performance in demanding outdoor tasks. Each model stands out with unique features and technologies tailored to meet various needs, from professional landscaping to residential gardening.

Starting with the Husqvarna 343R, this versatile trimmer is well-known for its lightweight design and powerful performance. It is equipped with a 34 cc engine that delivers a reliable power-to-weight ratio, making it ideal for extended periods of use without excessive fatigue. The 343R features a simple start system, ensuring an easy ignition, while its Tap 'n Go trimmer head permits effortless line feeding, enhancing productivity.

Moving on to the Husqvarna 345RX, this model is favored by professionals for its robust build and advanced technology. Powered by a 45.7 cc engine, it provides superior cutting power suited for heavy-duty tasks. The 345RX comes with an ergonomic handle and a comfortable harness that allows for better weight distribution, which reduces strain during long work sessions. Additionally, the machine's X-Torq engine technology reduces fuel consumption and emissions, making it an environmentally friendly option.

The Husqvarna 343F offers a modest yet efficient powerhouse with its 34 cc engine. It is user-friendly, making it an excellent choice for recreational users or those new to outdoor maintenance. This model features an adjustable handle to accommodate various cutting angles, enhancing versatility according to the user's preference.

Next is the Husqvarna 345FX, an exceptional tool for professional use, boasting a high-performing 45.7 cc engine. The 345FX incorporates advanced vibration dampening technology, resulting in reduced operator fatigue during lengthy operations. Its advanced cutting attachments provide versatility for tackling different vegetation types, enhancing user experience.

Finally, the Husqvarna 345FXT merges performance with functionality. Like the 345FX, it features a 45.7 cc engine with exceptional power, but comes with additional features such as an easy-to-adjust harness and advanced cutting heads. This model is particularly suited for demanding tasks, offering extended run time and increased efficiency.

In summary, Husqvarna’s 343R, 345RX, 343F, 345FX, and 345FXT trimmers are engineered with cutting-edge technologies. Each offers unique features that cater to the distinct needs of both casual users and professionals. These models ensure optimal performance, efficiency, and comfort, making them excellent choices for various outdoor maintenance tasks.
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