Husqvarna 325HS99X, 325HS75X manual Maintenance, Carburettor

Page 14

MAINTENANCE

Carburettor

Your Husqvarna product has been designed and manufactured to specifications that reduce harmful emissions. After the engine has used 8-10 tanks of fuel the engine will be run-in.To ensure that it continues to run at peak performance and to minimise harmful exhaust emissions after the running-in period, ask your dealer/service workshop (who will have a rev counter at their disposal) to adjust your carburettor.

WARNING! The complete clutch cover and

!gear housing must be fitted before the machine is started, otherwise the clutch may come loose and cause personal injury.

Function

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

•Adjusting the carburettor means that the engine is adapted to local operating conditions, e.g. climate, altitude, petrol and the type of 2-stroke oil.

•The carburettor has three adjustment controls: L = Low speed jet

H = High speed jet

T = Idle adjustment screw

L H T

•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 carburettor 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.

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

Recommended max. speed: See the Technical data section.

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.

Fine adjustment

•When the machine has been ”run-in” the carburettor should be finely adjusted. The fine adjustment should be carried out by a qualified person. First adjust the L-jet, then the idling screw T and then the H-jet.

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.

Low speed jet L

Try to find the highest idle speed by turning the low speed jet L clockwise then anti-clockwise. When the highest speed has been found, turn the low speed jet L 1/4 turn anti-clockwise.

L

+ 1/4

L

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.

Fine adjustment of the idle speed T

Adjust the idle speed with the idle adjustment screw T, if adjustment is necessary. First turn the idle adjustment screw T clockwise until the blades start to move. Then turn the idle adjustment screw T anticlockwise until the blades stop. The idle speed is correctly adjusted when the engine runs smoothly in every position. There should also be a clear margin to the speed at which the blades start to move.

14 – English

Page 13 Page 15
Image 14
Page 13 Page 15
Contents 325HS75X-SERIES 325HS99X-SERIES KEY to Symbols SymbolsContents Personal protective equipment Safety InstructionsMachine′s safety equipment Vibration damping system MufflerBlades Gear housing General safety precautionsAssembly of the catcher accessory Fuel safetySafety instructions while working Safety instructions when using the hedge trimmerSafety instructions regarding the surroundings Transport and storageSafety instructions after completing work Basic working techniquesWhat is WHAT? What is what?Fuelling Fuel HandlingFuel Starting and stopping Starting and StoppingCheck before starting Cold engineWarm engine StoppingMaintenance CarburettorHigh speed jet H Correctly adjusted carburettorMuffler Spark plug Cleaning the air filterCooling system Air filterMaintenance schedule Gear housingCleaning and lubrication Technical Data Technical dataEC-declaration of conformity Applies to Europe only Cispr 121997, EN7741140179-26

325HS75X, 325HS99X specifications

The Husqvarna 325HS99X and 325HS75X are two remarkable hedge trimmers designed for both professional landscapers and gardening enthusiasts. These models combine power, precision, and comfort, making them ideal for tackling a variety of hedging tasks.

The 325HS99X features a powerful 25.4 cc engine that delivers high performance while remaining fuel-efficient. With its long 39-inch cutting blade, operators can trim large hedges more efficiently, reducing the time spent on the job. The trimmer is equipped with a double-sided blade that cuts smoothly in both directions, allowing for faster work and cleaner cuts. This model also boasts an adjustable rear handle which can be rotated to optimize comfort during various cutting angles.

On the other hand, the 325HS75X features a slightly smaller 24.5 cc engine. Although it provides slightly lower power, it is still competent for a range of trimming tasks. The 30-inch cutting blade enables users to tackle moderate-sized hedges with ease. Like its counterpart, the 325HS75X also has a double-sided blade design, ensuring efficient operation and clean results.

Both models come equipped with Husqvarna's Anti-Vibration technology, which minimizes fatigue during prolonged use. This feature is crucial for professionals who need to use the trimmer for extended periods. Additionally, the ergonomic design of both models enhances user comfort, helping to ensure that operators maintain control even during extended sessions.

Moreover, starting these hedge trimmers is made easier thanks to Husqvarna's Smart Start technology. This system reduces the amount of effort needed to start the engine, ensuring that the trimmers are ready for action without unnecessary hassle. The air filtration system in both models helps prolong the life of the engine by keeping contaminants at bay, reducing maintenance and ensuring reliable operation over time.

In summary, the Husqvarna 325HS99X and 325HS75X hedge trimmers exemplify advanced engineering and design, making them indispensable tools for anyone serious about hedge trimming. With robust power, long blades for efficiency, and innovative features for user comfort, these hedge trimmers are built to handle the demands of both professional and household gardening tasks. Whether you're trimming dense shrubs or shaping hedges, the 325HS99X and 325HS75X offer reliability and performance that gardeners can depend on.
Top Page Image Contents