Jonsered GR41/50 manual Maintenance, Carburetor

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MAINTENANCE

Carburetor

Your Jonsered product has been designed and manufactured to specifications that reduce harmful exhaust fumes. The engine will be run in after it has used 8-10 tanks of fuel. To ensure that the engine runs at peak performance and produces as little harmful exhaust fumes as possible after the running-in period, ask your dealer/service workshop (which has a rev counter for this purpose) to adjust your carburettor.

WARNING! The complete clutch cover and

!shaft must be fitted before the machine is started, otherwise the clutch can come loose and cause personal injury.

Carburetor adjustment

The carburettor can be designed in different ways, depending on the existing environmental and emissions legislation. Some machines are equipped with movement limiters on the carburettor’s adjuster screws. These limit the adjustment range to a maximum of 1/2 turn.

1/2

1/2

Function

The carburetor governs the engine’s speed via the throttle control. Air and fuel are mixed in the carburetor. The air/ fuel mixture is adjustable. Correct adjustment is essential to get the best performance from the machine.

The setting of the carburetor means that the engine is adapted to local conditions, for example, the climate, altitude, fuel and the type of 2-stroke oil.

The carburetor has three adjustment controls: L = Low speed jet

H = High speed jet

T = Idle adjustment screw

RS44RS52

The L and H-jets are used to adjust the supply of fuel to match the rate that air is admitted, which is controlled with the throttle. If they are screwed clockwise the air/fuel ratio becomes leaner (less fuel) and if they are turned anti- clockwise the ratio becomes richer (more fuel). A lean mixture gives a higher engine speed and a rich mixture gives a lower engine speed.

The T-screw regulates the throttle setting at idle speed. If the T-screw is turned clockwise this gives a higher idle speed; turning it anti-clockwise gives a lower idle speed.

Basic setting

The basic carburetor settings are adjusted during testing at the factory. The basic setting is richer than the optimal setting and should be maintained for the first few hours the machine is in use. The carburettor should then be finely adjusted. Fine adjustment should be carried out by a skilled technician.

The basic setting can vary between: H = 1 - 1 1/4 turns and L = 1 - 1 1/4 turns.

CAUTION! If the cutting attachment rotates when the engine is idling the idle adjustment screw T should be turned anti- clockwise until the cutting attachment stops.

Rec. idle speed 2700 rpm

WARNING! If the idle speed cannot be

!adjusted so that the cutting attachment stops, contact your dealer/service workshop. Do not use the machine until it has been correctly adjusted or repaired.

CAUTION! The machine should only be run for short periods at its highest speed. For optimum adjustment of the carburettor, contact a qualified dealer/service workshop that has a revolution counter at their disposal.

Recommended max. speed: See the Technical data section.

During the running-in period (8-10 tanks of fuel) the maximum speed should be set 600-700 rpm below the recommended maximum speed (= open the high speed jet H a further 1/8 turn).

Conditions

Before any adjustments are made, make sure that the air filter is clean and the air filter cover is fitted. If you adjust the carburettor when the air filter is dirty it will result in a leaner mixture when the filter is finally cleaned. This can lead to serious engine damage.

Carefully turn both jets, L and H, so that they are midway between fully screwed in and fully screwed out.

Do not attempt to adjust the L and H jets beyond either stop as this could cause damage.

Now start the machine according to the starting instructions and let it warm up for 10 minutes.

CAUTION! If the cutting attachment rotates when the engine is idling the idle adjustment screw T should be turned anti-clockwise until the cutting attachment stops.

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Contents Operator’s manual EPA Symbols KEY to SymbolsContents Dear customer IntroductionWhat is what on the clearing saw? RS44 What is WHAT?What is what on the clearing saw? RS52 Personal protective equipment General Safety PrecautionsStop switch Machine′s safety equipmentThrottle lock Vibration damping system Cutting attachment guardQuick release MufflerLocking screw Locking nutCutting equipment Cutting equipmentSharpening grass cutters and grass blades Trimmer head Sharpening the saw bladeTransport position, handlebar AssemblyFitting a blade guard, grass blade and grass cutter Fitting the blade guard and saw blade Blade guard a is fitted using 4 screws L as shownFitting other guards and cutting attachments Adjusting the harness and clearing sawStandard harness Vector harness Adjusting the harnessCorrect balance Fuel Handling Fuel safetyFuel Mixing FuelingCheck before starting Starting and StoppingStarting and stopping Cold engineStopping StartingWorking Techniques Basic safety rulesGeneral working instructions ABC of clearingBrush cutting with a saw blade Forestry clearing using a saw bladeGrass trimming with a trimmer head Grass clearing using a grass bladeSweeping Carburetor MaintenanceLow speed jet L Fine adjustment of the idle speed THigh speed jet H GR41, GR50, RS44 High speed jet H RS52Muffler Correctly adjusted carburetorCooling system Air filterBevel gear Cleaning the air filterSpark plug Maintenance Daily Weekly Monthly Maintenance scheduleTechnical data Technical DataYour Warranty Rights and Obligations Federal Emission Control Warranty StatementTrimmy SII Page ´z+R!o¶5*¨ Page 1150017-95 ´z+R!o¶5*¨ ´z+R!o¶5*¨

GR41/50 specifications

The Jonsered GR41/50 is a robust and versatile garden tractor designed for both commercial and residential use. Known for its reliability and efficient performance, this model has become a preferred choice among landscaping professionals and homeowners alike.

One of the standout features of the Jonsered GR41/50 is its powerful engine. It typically comes equipped with a 500cc gasoline engine that ensures optimal performance. This engine provides ample power for tackling a variety of tasks, from mowing large lawns to handling more demanding gardening activities. The automatic transmission allows for smooth and effortless operation, enabling users to focus on their gardening tasks without the distraction of manual gear shifting.

The GR41/50 boasts a robust cutting deck, usually available in multiple sizes, allowing users to select the right width for their specific needs. The cutting height can often be adjusted easily, ensuring precision lawn care while catering to different grass types and growing conditions. This feature is particularly useful for achieving a well-maintained and healthy lawn throughout the changing seasons.

In terms of technology, the Jonsered GR41/50 features advanced steering mechanisms, often with a tight turning radius, making it easy to navigate around obstacles in the garden. This agility enhances productivity and ensures that users can cover ground more efficiently. Additionally, many models come equipped with ergonomic seating and controls, promoting comfort during prolonged use and reducing operator fatigue.

Durability is another significant aspect of the Jonsered GR41/50. Built with high-quality materials, this garden tractor is designed to withstand the rigors of frequent use. The sturdy frame and reliable components contribute to its long lifespan, making it a wise investment for those seeking a reliable gardening machine.

Moreover, the GR41/50 often includes a range of attachments and accessories, such as plows, tow-behind trailers, and snow removal equipment, transforming it into a multi-functional tool for year-round use. This versatility not only maximizes its utility but also provides excellent value for users.

In summary, the Jonsered GR41/50 is a well-rounded garden tractor that combines power, technology, and durability. With its remarkable features, user-friendly design, and adaptability to various tasks, it stands out as a top choice for anyone looking to enhance their gardening and landscaping efficiency.