Huter Trimmer Carburetor Adjustment

How to know that the lawn mower carburetor needs adjustment

Many craftsmen use lawn mowers for a long time, and at the same time do not think about the need to adjust the carburetor of the tool. When is it necessary to adjust the carburetor on a lawn mower or lawn mower? If you ask such a question, then for sure there are changes in the operation of the motor not for the better. In order not to guess, and not to miss the moment of the need to adjust the carburetor, you should adhere to the following recommendations on the need for adjustment measures:

After the engine has been run in. Typically, running-in lasts for burning 4-5 liters of fuel
When a fuel mixture of a different composition is poured into the tank, that is, the type of oil (even its color) and the brand of gasoline change
When weather conditions change, however, this is more relevant for chainsaws, gas generators and motor pumps, which are operated not only in summer, but also in winter.
If the lawn mower has not been used for a long time. The reason for the need for adjustment may be the winter break
When fuel consumption rises
If black deposits are found on the spark plug electrodes
In the absence of gasoline entering the cylinder or poor engine start
When detecting a large amount of exhaust gases
Unstable operation of the engine, as well as its difficult start and "sluggish" set of revolutions

As you can see, there are enough reasons to adjust the lawn mowing carburetor. Usually, craftsmen who work with the tool for a long time, by ear, detect changes in the operation of the motor, which promises the need for an adjustment process. Even if you are not sure of the need for adjustment work, then their extraordinary implementation will definitely not be superfluous.

When do you need to adjust the carburetor of a household trimmer?

Adjust the built-in carb trimmer when:

Starting a new engine that used 4.5 liters of fuel mixture;
Sudden weather changes;
Changes in air vacuum. For example, when a scythe is often used in mountainous areas;
Long simple trimmer;
Intensive growth of loads on the power unit of the mower;
Arbitrary unscrewing of the built-in carburetor adjusting screws. This causes increased vibration of the internal combustion engine;
Change in the quality of the components of the fuel mixture;
Fuel overflow by the carburetor, which leads to an increase in fuel consumption;
Regular occurrence of a thick layer of resin and soot deposits on the surface of the electrodes of a conventional three-dimensional spark plug;
Starting the engine and its accidental shutdown or low speed;
Lack of fuel in the cylinder of the power unit;
Exhaust gas increase.

READ Variable Speed Angle Grinder

The lack of timely adjustment of the carburetor threatens with serious damage to the trimmer, up to the complete failure of its factory engine.

Starting the motor

The engine is started at a distance of 3 m or more from the place where the device is refueled. This work must not be carried out indoors. Until you need to take a stable reliable position. With all this, the motor device is held very tightly. The cutting tool should not come into contact with the ground or objects, because when starting it can spin.

The unit is serviced by only one person, while third-party persons should not be in an area with a radius of up to 15 m. Otherwise, injury may be caused by thrown objects. Starting the motor of the Stihl FS 55 lawn mower, the properties of which are presented in the article, should not be carried out by hand. The cutting tool after releasing the throttle lever will move for some time by inertia. Flammable materials must be kept away from the hot gas flow and the surface of the hot muffler, because this may cause a fire.

Principle of operation

The procedure for pumping and filtering fuel in the lawn mower engine is as follows.

The throttle valve controls the amount of air supplied to the diffuser. The more air is supplied, the more oxygen the gasoline needs to burn, and the more power it gives off as heat. The heat energy is further converted into mechanical energy.
The diaphragm pump pumps the required amount of gasoline.
Next, gasoline passes through the engine fitting.
Fuel flows through the inlet and outlet valves.
Fuel is filtered using a mesh filter.
Through the needle valve, it also enters the chamber with the membrane.

The staging of the carburetor is as follows.

Air enters the duct with an air damper. The damper sets the desired intensity of air flow.
In the gasoline injection unit, the diffuser is narrowed - this is necessary to give a higher air flow rate.
Fuel passes through the float compartment and bypasses the jet, enters this constriction of the tube. The float compartment doses the supply of gasoline. In this compartment, the pressure is in equilibrium. In a narrowed tube, it decreases. Due to the difference in both pressure values, gasoline passes through the jet.
The accelerated flow atomizes the gasoline, converting it into aerosol vapors. The resulting gasoline-air mixture is ready for ignition in the combustion chamber.
After passing through the fuel pipeline, this mixture is in the carburetor cylinder.

Conclusion: to set the required power, first of all, you will adjust the rate of fuel combustion using the air damper. If the gap is too small, and oxygen in such a mixture is less than 10%, the fuel does not burn, therefore, the engine will not start or immediately stall.

In the case of buying a Chinese trimmer, it is worth considering that it differs little from European ones - the same 2- or 4-stroke engine and drive.

How to adjust the carburetor on a lawn mower

Before adjustment it is necessary to thoroughly clean the filters according to the maintenance manual.

Further adjustment of the carburetor of the lawn mower with your own hands is carried out with adjusting screws. There are three in total:

right;
left;
lower.

Right (L) - adjusting the fuel mixture for low speeds.

You need to find the maximum idle speed. To do this, slowly turn the screw (L) to the right and left.

To adjust, turn the screw a quarter of a turn, always counterclockwise.

Lower (T) - is responsible for adjusting the engine at idle.

clockwise - increase;
counterclockwise - decrease.

For the correct adjustment of the idle speed, it is characteristic:

stable operation of a cold engine;
not too high speed of a hot engine;
for a trimmer head a large margin of revolutions;
stable operation of the engine when changing position (a sharp rise or descent of the knife).

Left (H) - mixture adjustment at high speeds. (The screw is adjusted last).

Setting up the carburetor of the lawn mower with the last screw is done as follows:

Open the throttle to full, while giving full throttle. Turn the screw clockwise until the speed drops (in this case, orient by ear).
Turn the screw counterclockwise as slowly as possible until the engine runs unevenly.
Then turn back quite a bit, barely hearing a stable, smooth operation.
For a more visual application of skills, it is more convenient to consider the work of an experienced user:

Interestingly, from the point of view of the author of the video, the setting (its correctness) is determined by the color of the candle, and not just by the engine speed and stability.

The correct setting of the carburetor with your own hands in this case is the combustion of the fuel mixture without residue, the color of the candle should be light brown.

Trimmer carburetor. How to properly adjust a trimmer carburetor.

December 03, 2021

On trimmers, in addition to electric motors, gasoline internal combustion engines are installed. This mechanism requires special attention to itself, because if it is incorrectly configured, it will either refuse to work, or will work intermittently and lose power. Basically, engine tuning consists in adjusting the fuel supply, and this is done using a trimmer carburetor.

The standard design of any gasoline trimmer necessarily includes a fuel system, the basis of which is the operation of a standard carburetor. Its device and the initial principle of operation are almost the same for all lawn mowers, regardless of their design features and purpose.

The lawn mower carburetor consists of an all-metal aluminum housing that protects the internal components of the assembly from moisture, small debris and dust. At the bottom of the housing there is a built-in diffuser, the second name of which is the “Venturi nozzle”. The main function of this standard part is to supply air in the amount that the fuel assembly requires to enrich the fuel. The diffuser works according to a simple principle: the smaller its diameter becomes, the more intensively air is sucked in. This is due to the fact that in the zone of the smallest diameter, the level of air discharge becomes maximum.

The top part of the built-in factory diffuser is pre-equipped with fuel pipes, through which, under the influence of air, the fuel mixture is drawn in. The remaining parts of the carburetor: regular adjusting screws and a fuel pump, can be located both inside and outside the carburetor.

The motokosa carburetor device includes a throttle valve, the main task of which is to regulate the volume of intake air. The greater the amount of air, the higher the power rating of the trimmer power unit. Another function of the damper is to facilitate the cold start of the engine. If the brushcutter is started for the first time after a long period of inactivity, the damper must be closed. Immediately after starting the engine, the part must be opened, otherwise the internal combustion engine will stall.

The carburetor for the trimmer is equipped with a pulse channel that connects the internal cavity of the engine crankcase with the pulse chamber of the pump. The piston located in the engine cylinder creates reciprocating movements, which leads to gradual changes in pressure inside the crankcase. At the same time, the membrane is set in motion. Thus, the action of the pump is fully synchronized with the operation of the power unit.

The membrane of the regular carburetor takes an active part in the suction of fuel. It enters the fuel assembly through the fitting. After that, the fuel passes through the built-in inlet and outlet valves, then through the strainer and fuel pipe. Then the fuel flows next to the needle and gradually fills the chamber equipped with a control membrane.

The regular valve of the trimmer carburetor is connected to the membrane with a lever. Below the built-in membrane is a cavity into which air is sucked through a special hole.

The carburetor for lawn mowers works according to this principle in stages. This ensures continuous operation of the fuel unit and uninterrupted supply of fuel to the cylinder of the standard power unit.

When is it necessary to adjust the carburetor of a household trimmer? You need to adjust the built-in trimmer carburetor when:

running-in of a new engine, during which 4 to 5 liters of fuel mixture were used;
sudden changes in the weather;
changes in air rarefaction - for example, when a lawn mower is often used in mountainous areas;
prolonged downtime of the trimmer;
intensive growth of loads on the power unit of lawn mowers;
arbitrary unscrewing of the built-in carburetor adjusting screws - this causes increased vibration of the internal combustion engine;
change in the quality of the components of the fuel mixture;
transfusion of fuel by a carburetor, resulting in an increase in fuel consumption;
the regular appearance of a thick layer of resinous deposits and soot on the surface of the electrodes of a standard trimmer spark plug;
starting the engine and its arbitrary shutdown or slow speed increase;
lack of fuel entering the cylinder of the power unit;
increase in the volume of exhaust gases emitted.

The lack of timely adjustment of the carburetor threatens with a serious breakdown of the trimmer, up to the complete failure of its factory engine.

Do-it-yourself lawn mowing carburetor adjustment. Periodic adjustment of the trimmer carburetor should be performed on a serviced and fully serviceable power unit. Before starting the procedure, the operator must thoroughly rinse the ICE parts and inspect its CPG for burrs or other defects. In addition, you will need to clean or change the spark plug, as well as rinse the filter elements in the design of the lawn mower.

When adjusting the carburetor, the lawn mower engine must be running under a certain load. It is best to install a cord of the appropriate diameter or cutting knives on the trimmer.

After installing the cutting elements, the operator must start the engine of the trimmer and leave it to work for about 10 minutes. If during the operation of the power unit at idle it was noticed that the cord or knife was rotating, then it was necessary to reduce the speed created by the motor. To do this, turn the lower control, often indicated by the letter "T", to the left until the installed cutting element comes to a complete stop. A further scheme for setting up the fuel assembly is as follows:

The "L" regulator, located on the right, is responsible for enriching the fuel mixture with air while the engine is running at low speeds. The position of this screw must be adjusted first. To do this, the operator will need to achieve maximum engine speed when idling - to do this, turn the screw "L" alternately to the right or left. As soon as the maximum speed is reached, the screw will need to be turned 1/2 turn to the left;
The "T" or "LA" screw is needed to adjust the idle speed. While turning it to the left, the speed of the power unit will decrease, and when turning to the right, it will increase accordingly;
The “H” regulator, provided on the left, is responsible for enriching the fuel mixture with air when the trimmer engine is operating at high speeds. This screw is also needed to adjust the engine power and the amount of fuel consumed. Its position is adjusted by turning the screw to the right or left until the maximum allowable engine speed is reached. After that, screw "H" will need to be turned 1/2 turn to the left.

Common faults in carburetors. Trimmer carburetor breakdowns occur due to the use of poor quality gasoline, a damaged air filter and the accumulation of dirt in the chamber of this unit. Most often, it is quite possible to repair the carburetor with your own hands. The following are typical scythe carburetor malfunctions.

Fuel pump problems. A common malfunction that "haunts" the fuel pump is the deformation of the pumping membrane. For this reason, it does not fit properly and the pumping channels do not seal.

The causes of membrane deformation can be the following:

long trimmer operation;
use of unsuitable fuel;
ingress of gases into the impulse channel.

As a result, diaphragm damage reduces the performance of the pump, and as a result:

depletion of the combustible mixture occurs;
difficult to start the engine;
there are interruptions in the operation of the motor;
piston is damaged.

Also, the above-described consequences for the engine can cause clogging of the pump cavity on the impulse side. In this case, dirt enters the membrane through the impulse channel.

To eliminate the blockage, you will have to disassemble the carburetor and clean the membrane.

Clogged strainer The strainer may become contaminated when contaminated fuel enters through a defective fuel hose or suction head. In the photo below you can see how a clean filter and a dirty filter look like (the parts are separated by a line).

To eliminate the malfunction, a thorough cleaning and rinsing of the strainer will be required. It is also recommended to blow out all the holes in the trimmer carburetor body with compressed air.

Faulty adjusting lever This failure occurs when the contact surface of the lever wears out.

The abrasion of the contact surface occurs due to the presence of abrasive particles in gasoline or due to strong vibration of the motor during operation. This defect in the adjusting lever causes intake problems, as well as improper idling of the engine.

Inlet needle wear Inlet needle failure is usually caused by abrasive particles in the fuel fluid.

As a result:

the tightness of the inlet needle seat is violated;
there is a leakage of the combustible mixture;
there are malfunctions in the operation of the engine associated with the re-enrichment of the fuel mixture.

Also, the inlet needle can simply jam.

A stuck inlet needle can cause dirt in the fuel, or a long idle time of the machine without operation.

Clogging of the adjusting cavity If dirt accumulates in the adjusting cavity, the inlet needle cannot tightly close the hole and a lot of fuel is poured into the chamber.

This causes the fuel to become richer and the engine starts to run incorrectly. It is necessary to disassemble the carburetor and clean the cavity of the adjusting membrane.

Deformation of the control diaphragm The diaphragm may be deformed during long-term operation of the unit and when using aggressive fuel.

The impossibility of normal adjustment due to a defect leads to:

piston damage;
difficulty starting;
fuel depletion;
incorrect engine operation.

Problem with the inlet adjusting lever This problem can occur if the adjusting lever is installed incorrectly or bent before installation. As a result, the contact surface assumes an incorrect position, which disrupts the additional fuel supply.

Damper wear Throttle and choke dampers are mainly worn due to the presence of abrasive particles in the air. Defective shutters look like they have been sandblasted.

As a result of valve wear, engine performance decreases, malfunctions appear in its operation, piston rings, piston and cylinder coating wear out.

Throttle and choke shaft wear The choke and choke shaft can wear for the following reasons:

insufficient and improper maintenance of the air filter;
the air filter is damaged;
the air filter is not suitable for this unit.

Due to the ingress of poorly purified air, the shaft wears out and may break. Broken shaft parts can enter the combustion chamber or crankcase and cause serious damage to the entire piston system.

To eliminate problems with air purification, it is necessary to replace the defective filter or rinse the existing (serviceable) one. The filter must be washed in soapy water and dried.

How to properly adjust Before starting to adjust the trimmer carburetor, you must do the following:

flush the engine;
replace or clean the spark plug;
change to a new one or clean the air filter (it is recommended to wash it in warm, soapy water, wring it out and let it dry well).

It is also necessary to install a cord of a suitable diameter in a trimmer coil or install knives - this is done so that the engine has at least some load during the tuning process. After installing the cutting tool and starting the gasoline engine, allow it to warm up for 10 minutes.

If at idle you notice that the cutting tool is rotating, then you need to reduce the engine speed. This is done using the lower idle control, often marked with the letter “T”. But, for example, on a Stihl trimmer, this screw may be marked “LA”.

So, turn the idle speed control to the left until the trimmer head stops completely.

To adjust the carburetor, 3 regulators (screws) are used.

The right control L adjusts the level of enrichment of the combustible mixture at low speeds. It needs to be adjusted first. Achieve maximum idle speed. This is done with the L knob, turning it left and right. After finding the point of maximum speed, return the regulator a half turn to the left (counterclockwise).
The lower regulator T (LA) is used to set the idle speed. By turning it to the left, the engine speed will begin to decrease, and by turning the knob to the right, the engine speed will increase.
The left control H is responsible for enriching the combustible mixture at high speeds. The enrichment setting completes the carburetor adjustment. Also, using this regulator, you can adjust the maximum speed, fuel consumption and engine power.

Important! If the engine is allowed to run at full speed for more than 10 seconds, it may fail.

To eliminate this trouble, adjustment is required. With the engine running, give full throttle, then turn knob “H” to the right until the RPM starts to decrease. After that, the "H" knob must be slowly scrolled to the left until you hear the uneven operation of the engine. Then turn knob “H” to the right until you hear a smooth running of the motor.

After carrying out the above steps, the carburetor setting can be considered completed. After correct adjustment, the engine should confidently gain momentum, quadruple a little at maximum speed, and when idling, the cutting tool should not rotate. This manual is suitable for adjusting carburetors on Huter, Patriot and other lawn mowers.

There are also carburetors without a screw, which is responsible for enriching the combustible mixture at low revs. That is, they have only 2 adjusting screws: the idle speed regulator and the fuel mixture quality regulator at high speeds.

The principle of operation of the carburetor lawn mowers

The throttle valve determines the amount of air to supply, and the power of the motor directly depends on this.

Carburetor option correctness

determined by the operation of the motor and the color of the candle. Adjusted

Self-tuning carburetor

on a Chinese trimmer, quickly and simply set
the carburetor
to

Fuel is sucked into the carburetor system by a pump (its membrane). Then it passes through the fitting in the carburetor. Further, the liquid moves through the inlet and outlet valves of the pump. Filtered out by the grid. It moves along the needle valve into the membrane chamber.

Step by step operation of the device:

Air supply to a tube with an air partition (flap). The baffle regulates the intensity of the air flow.
The fuel supply system is necessarily narrowed by a mixer to speed up the flow.
Gasoline through the float chamber and jet tube with a narrowing. The float chamber regulates the temporary amount of gasoline. In the float chamber, the pressure level is neutral, and in the constriction tube it is already low. Due to the pressure drop, fuel seeps through the jet.
The acceleration of the air flow promotes the transfer of fuel (gasoline) and its atomization. In the end, an air-fuel mixture of the desired proportion or density appears.
The air-fuel mixture seeps into the engine cylinder through the fuel pipe.

The level of air density in the system depends on the area of the open air damper. The wider the damper is open, the greater the fuel consumption and power.

Simply put, adjusting the carburetor on a lawn mower is creating a good fuel consistency due to the correct air supply.

Do-it-yourself lawn mowing carburetor adjustment

Regardless of the model of garden tool, trimmer carburetor adjustment requires careful preparation. The owner of the lawn mower will need to check the spark plug, air filter and the carburetor itself. In case of contamination, all elements must be cleaned or, if necessary, replaced.

The trimmer comes standard with 3 adjustment screws. The first of them is marked with the letter L, and serves to tune the engine when it is running at low speeds. The second bolt is marked with the letter H, and is necessary to adjust the internal combustion engine when it is operating at the highest possible speed. The third bolt may be marked with the letters T or LA - with its help the operator can adjust the engine to idle.

The process of setting up a lawn mowing carburetor is as follows:

First you need to carry out a series of actions with the adjusting bolt L. To do this, turn it clockwise until it stops. After that, the bolt L will need to be turned half a turn in the opposite direction. This will make it possible to adjust the optimal enrichment of the fuel mixture with oxygen when the engine is running at low speeds;
Then you need to adjust the operation of the internal combustion engine in idle mode. To do this, alternately turn the bolt T in different directions until the mowing head or knife stops rotating;
In the end, you will need to adjust the level of fuel enrichment with oxygen when the engine is running at maximum speed. To do this, the bolt H will need to be turned clockwise until it stops, then return it 1/2 turn in the opposite direction.

At the end, the operator must turn off the trimmer motor and start it again. If the unit has been configured correctly, then the lawn mower engine will confidently gain momentum when the gas trigger is pressed, and quickly reset them when the trigger is released.

How to adjust the carburetor on a lawn mower

The upcoming adjustment of the carburetor of the lawn mowers with your own hands is done with adjusting screws. There are three in total:

Right (L) - adjustment of the fuel consistency for low revs.

It is necessary to find the highest idle speed. To do this, slowly unscrew the screw (L) to the right and left.

To adjust, turn the screw a quarter of a turn, without fail counterclockwise.

Lower (T) - is responsible for adjusting the engine at idle.

clockwise - increase;
counterclockwise - decrease.

For the correct adjustment of specifically idling, it is characteristic:

stable operation of a cold engine;
not too high speed of a hot engine;
for a trimmer head a large margin of revolutions;
stable operation of the engine when changing position (a sharp rise or descent of the knife).

Left (H) - mixture adjustment at high speeds. (The screw is adjusted last).

From the left screw (H) depends on the overall adjustment of maximum speed, engine power, temperature and gasoline consumption.

Setting up the carburetor of the lawn mower with the last screw is done as follows:

Open the throttle to full, while giving full throttle. Turn the screw clockwise until the speed drops (in this case, orient by ear).
Turn the screw counterclockwise as slowly as possible until the engine runs unevenly.
Then turn back quite a bit, barely hearing a stable, smooth operation.
For a more visual application of skills, it is more convenient to consider the work of an experienced user:

Interestingly, from the point of view of the author of the video, the setting (its correctness) is determined by the color of the candle, and not just by the engine speed and stability.

do it yourself

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How to clean a carburetor on a trimmer

Motokosa carburetor repair Very often, complaints from the owners of gasoline trimmers are associated with various kinds of carburetor defects. Naturally, it is best in this case to seek help from a specialist.

Content

Carburetor Repair

Very often, complaints from owners of gasoline trimmers are associated with various kinds of carburetor defects.

You can also watch a video repair of a lawn mower (trimer) (part 1 - disassembly)

Do-it-yourself lawn mowing carburetor adjustment, repair and tuning, the principle of operation of the device, video

Lawn mowers, like all garden tools, are not difficult to maintain equipment. It is possible and necessary to repair, adjust without the help of others. For example, adjusting the carburetor of a lawn mower with your own hands is a matter of 5 minutes.

A carburetor from a lawn mower is a node in the power system. In it, like all carburetors, there is a process of mixing air and fuel (gasoline) for the upcoming supply to the engine cylinders.

In this process, the main thing is the correct proportion of fuel and air, which is why the carburetor is regulated.

The main problems and malfunctions of the carburetor.

Mesh filter. There are only two difficulties with this element:

In order to find out the cause of the breakdown, the fuel filter cap is unscrewed to remove the strainer. If dirt has simply accumulated on it, then washing in gasoline or blowing will help.

In case of visible damage to the mesh filter, it is imperative to install a new one. There may also be damage to the fuel supply pipe (during repairs, it is practiced to check this element).

The carburetor starter almost always does not work due to blockages. Use acetone or the same gasoline for flushing.

READ How to Change Gearbox to Echo Trimmer

Blowing out clogged carburetor parts with compressed air is an acceptable and comfortable repair practice.

The throttle body, the places of ligaments of carburetor parts, the inlet or outlet pipeline - all of these parts are subject to depressurization. You can probably check with a simple method - smear the problem area with soapy foam.

The device of the carburetor lawn mowers

The base of the carburetor of the lawn mower is an duralumin case. It contains a diffuser (hole with internal contours). Air is forced through this hole. The flow rate of oxygen (air) supply depends on the cross section (through hole) of the diffuser.

The diffuser is equipped with fuel channels. Fuel is drawn from them with the help of air flow.

Outside, the carburetor is installed:

fuel pump;
jet system;
System for adjusting the consistency of fuel with air;

The principle of operation of the carburetor lawn mowers

The throttle valve determines the amount of air to supply, and the power of the motor directly depends on this.

Step by step operation of the device:

Air supply to a tube with an air partition (flap). The baffle regulates the intensity of the air flow.
The fuel supply system is necessarily narrowed by a mixer to speed up the flow.
Gasoline through the float chamber and jet tube with a narrowing. The float chamber regulates the temporary amount of gasoline. In the float chamber, the pressure level is neutral, and in the constriction tube it is already low. Due to the pressure drop, fuel seeps through the jet.
The acceleration of the air flow promotes the transfer of fuel (gasoline) and its atomization. In the end, an air-fuel mixture of the desired proportion or density appears.
The air-fuel mixture seeps into the engine cylinder through the fuel pipe.

The level of air density in the system depends on the area of the open air damper. The wider the damper is open, the greater the fuel consumption and power.

Simply put, adjusting the carburetor on a lawn mower is creating a good fuel consistency due to the correct air supply.

How to adjust the carburetor on a lawn mower

Before adjustment, you need to carefully clean the filters according to the maintenance in the annotation.

The upcoming adjustment of the carburetor of the lawn mowers with your own hands is done with adjusting screws. There are three in total:

Right (L) - adjustment of the fuel consistency for low revs.

It is necessary to find the highest idle speed. To do this, slowly unscrew the screw (L) to the right and left.

To adjust, turn the screw a quarter of a turn, without fail counterclockwise.

Lower (T) - is responsible for adjusting the engine at idle.

Clockwise - increase;
Counterclockwise - decrease.

For the correct adjustment of a specific idle speed, it is typical:

Stable operation of a cool motor;
Not over-revving a hot engine;
For a trimmer head, a large supply of revolutions;
Stable operation of the motor when changing position (a sharp rise or descent of the knife).

Left (H) - adjusting the consistency at high speeds. (The screw is adjusted last).

The general adjustment of the maximum speed, engine power, temperature and gasoline consumption depends on the left screw (H).

Setting up the carburetor of the lawn mower with the last screw is done as follows:

Trimmer Carburetor Cleaning

Spare parts for Chinese lawn mowers Chinese lawn mower repair

Carburetor cleaning in Champion T266 trimmer

If you have problems with the work of a Chinese lawn mower ( trimmer

), it does not start or does not work well, then it is more.

Open the throttle to full, while giving full throttle. Turn the screw clockwise until the speed drops (in this case, orient by ear).
Turn the screw counterclockwise as slowly as possible until the engine runs unevenly.
Then turn back quite a bit, barely hearing a stable, smooth operation.
For a more visual application of skills, it is more convenient to consider the work of an experienced user:

Interestingly, from the point of view of the author of the video, the setting (its correctness) is determined by the color of the candle, and not just by the engine speed and stability.

Correct setting of the carburetor with your own hands

in this case, the combustion of the fuel mixture without residue, the color of the candle should be light brown.

Lawn mowing carburetor adjustment in practice - video

Do-it-yourself lawn mower repair: main malfunctions and their elimination

A benzokosa is one of the main tools of a summer resident used to quickly bring the land in order. This tool is purchased for mowing grass in the backyard and the owners of private houses. The period of active use of lawn mowers and electric trimmers falls on the summer period. Before starting operation, the tool is put into working condition: rubbing parts are lubricated, the cutting set is changed, the fuel mixture is poured into the tank. If the engine does not start at all or stalls quickly, without gaining a sufficient number of revolutions, then you have to look for the causes of the malfunctions and eliminate the identified malfunctions. To repair lawn mowers with your own

hands, it is necessary to understand its structure and the principle of operation of the main nodes. This information can be found in the operating instructions, which the manufacturer applies to garden equipment without fail. Check for such a manual when buying a chainsaw. An imported tool must be accompanied by an instruction written in Russian.

READ Stihl Trimmer Carburetor Adjustment

How is a household lawn mower arranged?

A long tubular rod is attached to the gearbox of a two-stroke internal combustion engine. A shaft passes inside the bar, transmitting torque from the gasoline engine to the cutting mechanism. The fishing line or knives rotate at a frequency of 10,000 to 13,000 rpm. In the protective housing of the gearbox, there are holes into which grease is injected using a syringe. For ease of use of the tool, the manufacturer equips it with a special adjustable shoulder strap.

The cutting set is attached to the lawn mowers:

The fishing line, the thickness of which varies from 1.6 to 3 mm, is located in the trimmer head. When mowing grass, the line is subject to wear. Changing the line is quick and easy in two ways: by winding line of the same diameter onto a bobbin or by installing a new spool with already wound line.
Steel knives with double-sided sharpening for a lawn mower for cleaning the area from weeds, small shrubs, hard grass. Knives differ in shape, as well as the number of cutting surfaces.

On the U-shaped, D-shaped or T-shaped handle attached to the bar, there are control levers for the brushcutter. The cutting mechanism is protected by a special casing. Household lawn mowers are refueled with a mixture prepared from gasoline and oil, which is poured into the fuel tank. The device of semi-professional and household lawn mowers equipped with a fourfold gasoline engine is slightly different. The refueling scheme is also different: oil is poured into the crankcase, and gasoline is poured into the tank.

The measured piece of fishing line is folded so that one end is 15 cm longer than the second. We put the loop into the slot on the reel and start winding it in the direction indicated by the arrow

What to do if the engine does not start?

If it is not possible to start a lawn mower, then the first thing to do is to check the presence of fuel in the tank and its quality. To refuel the tool, it is recommended to use high-quality gasoline purchased at gas stations, the brand of which must be at least AI-92. Saving on cheap fuel can lead to a breakdown of the cylinder-piston group, the repair of which can take a third of the cost of the lawn mower itself. Equally important and correctly prepare the fuel mixture of gasoline and oil. The proportional ratio of these components of the mixture is indicated by the manufacturer in the manual. Do not prepare the fuel mixture in large volumes, as long-term storage loses its properties. It is better to use a freshly prepared mixture.

When preparing the fuel mixture, pour the oil into gasoline using a medical syringe, which allows you to accurately maintain the required proportion of components

A clogged fuel filter in the tank can also interfere with the engine of the lawn mower. Therefore, if you have problems starting the engine, check the condition of the filter. Replace the filter if necessary. It is forbidden to leave the inlet pipe without a fuel filter.

The air filter also needs to be checked. When contaminated, the part is removed, washed in gasoline in the field and put in place. In the country or at home, the filter can be washed in water using detergents. After that, the filter is rinsed, wrung out and dried. The dried filter is moistened with a small amount of oil used to prepare the fuel mixture. Excess oil is removed by squeezing the filter with your hands. The part is then put into place. The removed cover is put back and fixed with screws.

The air filter, washed in the fuel mixture, wrung out and dried, is put in place in a plastic case and closed with a lid

How this procedure is done in more detail you can see on the video:

If all of the above procedures are carried out, and the engine does not start, then adjust its idle speed by tightening the carburetor screw. In the video posted at the beginning of the article, attention is paid to this issue.

Quick Start Tips

So, in order:

Lay the tool on its side so that the air filter is at the top. With this arrangement of the chainsaw, the fuel mixture is ensured exactly at the bottom of the carburetor. On the first try, the engine will start if you remove the air filter before starting and pour a few drops of the mixture into the carburetor
, then reinstall the dismantled parts. The method has been tested in practice.
If the first tip does not work, then most likely the problem is in the spark plug. In this case, unscrew the spark plug and check its performance, and also dry the combustion chamber. Replace the spark plug that shows no signs of life with a new one.
If the spark plug is in good condition, the filters are clean and the fuel mixture is fresh, then you can use the universal way to start the engine. Close the carburetor choke and pull the starter handle once. Then open the throttle and pull the starter 2-3 more times. Repeat the procedure three to five times. The engine will definitely start.

Some pull the handle with such force that they have to repair the starter of the lawn mower with their own hands. This is only possible if the cable breaks or the cable handle breaks. In other cases, it is recommended to replace the starter. This unit is sold as a set.

READ Husqvarna 137 Chainsaw Carburetor Adjustment Video

How to replace the spark plug correctly?

The order of work is as follows:

Stop the engine and wait until it cools down.
Disconnect the high voltage wire from the spark plug.
Unscrew the part using a special key.
Inspect the spark plug for replacement. The part is replaced if it is faulty, heavily soiled, has a crack on the body.
Check the gap between the electrodes. Its value should be 0.6 mm.
Tighten the new spark plug inserted into the engine with a wrench.
Spend installation of a high-voltage wire on the central electrode of a candle.

As you can see, there is nothing super complicated in this procedure.

A new spark plug for a two-stroke internal combustion engine of a gasoline scythe is installed to replace the old part that failed

Why does the lawn mower stall after starting?

After starting, the engine may stall if the carburetor is incorrectly adjusted or misaligned. By what signs can one understand that the reason really lies in this? Very simply, by the vibrations that will be clearly felt during the operation of the lawnmower. You can adjust the fuel supply with your own hands by doing everything that is written in the instruction manual for the tool.

The engine may stall due to a clogged fuel valve. The cause is eliminated by cleaning it. If the lawn mower starts up, and then abruptly stalls, it means that the fuel supply to the carburetor is difficult. Loosen the carburetor valves to ensure that fuel flows freely to it in the right amount.

Too much air can also stall the engine. Increase the engine speed so that air bubbles exit the unit's fuel system more quickly. Also be sure to check the integrity of the fuel intake hose. In case of detection of mechanical damage (cracks, punctures, etc.), replace the part.

How to clean and store the instrument?

During the operation of the lawn mower, monitor the condition of the engine cooling system. The channels in the starter housing, as well as the cylinder ribs, must always be kept clean. If you ignore this requirement and continue to operate the lawn mower, you can disable the engine due to overheating.

Competent care of a gasoline scythe during the period of operation allows you to use it for several seasons in a row without major repairs.

Allow the engine to cool before cleaning. Take a soft-bristled brush and clean the outer surface of the dirt. Cleaning of plastic parts is carried out with solvents, including kerosene, or special detergents.

At the end of the summer season, the lawn mower should be prepared for long-term storage. To do this, the fuel mixture is drained from the tank. Then the engine is started in order to develop the remaining fuel in the carburetor. The entire tool is well cleaned of dirt and sent to "hibernation".

As you can see, it is quite possible to repair malfunctions of household lawn mowers on your own. Service should be contacted in case of serious breakdowns. In this case, the cost of repairs should be correlated with the price of a new lawn mower. It might be better to buy a new instrument.

Do-it-yourself lawn mowing carburetor adjustment. trimmer carburetor

A modern gasoline-powered trimmer is a complex unit, which also includes a carburetor. It is from its reliable and correct operation that the performance of the work will depend. Trimmer carburetor adjustment should be performed in the following cases:

After running the engine (as a rule, this requires 4-5 liters of gasoline);
Before the start of the mowing season;
If, during operation, the adjusting screws arbitrarily loosen due to vibration.

Taking into account the fact that the trimmer does not belong to the category of complex units, you can do the carburetor adjustment yourself.

Functions and working principle

In order to understand how the lawn mower carburetor works, it is worth getting acquainted with its principles of operation. The main elements of the carburetor include the throttle valve, the function of which is to control the air supply. The operation of such a device as a carburetor can be considered in stages.

The air mixture is supplied to the compartment where the throttle valve is located.
The moving air stream helps to move and atomize the fuel through the jet.
The resulting mixture (air-fuel) is fed into the engine cylinder.

Having become acquainted with these main stages, we can conclude: the more the throttle valve is open, the greater the gasoline consumption during the mowing process.

Carburetor adjustment for lawn mowers

Before proceeding with the adjustment, you need to very carefully clean

filters. This work must be carried out in accordance with the manufacturer's instructions. Further work on the carburetor is done by adjusting the three screws.

The right screw is for adjusting the air-fuel mixture. Turning the screw to the right and left is performed at idle. It is necessary to determine the maximum speed.
The left screw is the adjustment of the air-fuel mixture. Work is carried out at high speed. The screw is adjusted last, the engine power and gasoline consumption will depend on its correct setting.
The bottom screw is for adjusting the engine. Work is done at idle. Clockwise rotation indicates an increase, anti-clockwise rotation indicates a decrease.

How does a lawn mower carburetor work or the principle of operation

The adjustment of the carburetor of the Chinese lawn mower is completely identical to the setting of the lawn mowers of European, Russian and manufacturers. To cope with the task of adjusting the carburetor on lawn mowers and gas trimmers, it is necessary to understand the principle of their functioning. How the carburetor works on a lawn mower is described step by step and accessible below.

The operation of the lawn mower carburetor begins with the supply of fuel through the channel, as shown in the diagram.
Fuel is sucked into the carburetor by means of an impulse channel connected to the crankcase. Due to rarefaction of air, the flexible membrane at number 4 in the diagram above moves.
Fuel is supplied through valves 3 and 5. Valve 3 is an inlet, due to which fuel is supplied to the submembrane space, and valve 5 is an outlet
Further, the fuel moves along the channel and, passing through the fine filter, reaches the needle valve 14
The needle valve is connected by means of a lever to the control diaphragm 18
The needle valve is actuated by impact on the membrane. When it is necessary to pump fuel to start the engine, the soft cover of the hand pump must be actuated. When exposed, the needle opens, and the fuel mixture fills the chamber
When the engine starts (cold), the opening of the needle occurs due to vacuum with the air damper closed. This vacuum acts through the idle and high speed jets on the membrane 18
The membrane acts through the lever on the needle valve, whereby the chamber is filled
After starting the engine, the choke valve opens, causing the engine to run lean as the fuel mixes with the air.
When the chamber is full, the fuel mixture is supplied (sucked in) through the idle and medium speed jets (when the engine is running)
The throttle valve is shifted from its original position by 10-15 degrees
When work is carried out under load, the fuel begins to flow into the chamber through the high-speed jet, and at the same time the throttle valve rotates up to 90 degrees (depending on the force of pressing the gas). In all operating modes, the air damper must be open, through which the fuel is mixed with air, and thereby the mixture in the cylinder is ignited

Below is a diagram of the principle of operation of a lawn mower carburetor. Based on the scheme, you can not only understand the principle of operation, but also identify breakdowns and other malfunctions of the mechanism.

When operating the tool, it is necessary to take into account the presence of another jet. This jet is located between the idle and full power channels. It is necessary in order to exclude a strong depletion of the mixture, which occurs when the engine is running at part load. In such a situation, the occurrence of a badass pair is not excluded. Through an additional channel (jet), fuel is sucked into the chamber, whereby the fuel-air mixture is enriched. The diagram below shows an additional jet, which is indicated by the number 1.

Having an idea about the design of the scythe membrane carburetor and the principle of operation, it will not be difficult to set it up with your own hands. To adjust the carburetor of the lawn mower, adjusting screws are used. The diagram above shows two adjustment screws, but most modern petrol trimmers are equipped with three screws. The presence of three tuning screws allows for more precise adjustment, while achieving stable and uninterrupted operation of the internal combustion engine.

This is interesting!
What is the difference between a trimmer and a lawn mower? Many people think that the trimmer is a low-power electric lawnmower. However, a trimmer is a generalized name for lawn mowers, brush cutters and electric mowers, since they are designed for general purposes.

Instructions for cleaning the carburetor of lawn mowers: a quick way

Many people prefer to use the quick way to flush the carburetor of the lawn mower. This method is effective when single device malfunctions are detected. Consider step by step how the process of disassembly and cleaning with your own hands takes place:

To begin with, from the side of the primer, it is necessary to unscrew the four fixing bolts.
We will clean only the part where the membrane is installed, that is, the lower one. To do this, we disconnect the parts and, using a gun from the compressor, proceed to blowing with compressed air.
We blow out part of the carburetor with jets.
We remove the mesh, and blow it gently so as not to damage it. Its contamination indicates the need to clean the channels.
We check the condition of the foot (rocker arm) connected to the needle valve. It should not be bent, and move freely. Using gasoline or WD-40, it is necessary to check the serviceability of its operation. After filling the bath in which the foot is located, you must press it. If fluid flows out of the needle valve, then it is functioning properly.
After making sure that the foot (rocker arm) is working properly, you can assemble the product.
Assembly is carried out in the reverse order of dismantling.
At the end, install the cover with the primer, and tighten with 4 fixing screws.

After the carburetor has been cleaned with compressed air, do not rush to put it on the lawn mower. Now you can check the serviceability of its functioning, or rather, how it pumps fuel. To do this, connect the hoses to the outlet fittings.

We lower the supply hose into a canister of gasoline, and pump the primer.

If gasoline flows out of the return line, it means that the work on cleaning the carburetor has been completed successfully. Now you can install the part on the lawn mower and check the quality of the tool. This completes the process of quick cleaning of the product. In more detail, the entire cleaning procedure is presented in the video.

The principle of operation of the carburetor lawn mowers

The throttle valve determines the amount of air to supply, and engine power directly depends on this.

Fuel is sucked into the carburetor system by a pump (its membrane). Then it passes through a fitting in the carburetor. Next, the liquid moves through the inlet and outlet valves of the pump. Filtered out by the grid. It moves through the needle valve into the membrane chamber.

Step by step operation of the device:

Air supply to a tube with an air partition (flap). The baffle regulates the intensity of the air flow.
The fuel supply system is necessarily narrowed by a diffuser to increase the flow rate.
Gasoline through the float chamber and jet tube with a narrowing. The float chamber regulates the temporary amount of gasoline. In the float chamber, the pressure level is neutral, and in the constriction tube it is already low. Due to the pressure drop, fuel penetrates through the jet.
The acceleration of the air flow contributes to the transfer of fuel (gasoline) and its atomization. As a result, an air-fuel mixture of the required proportion or density is formed.
The air-fuel mixture enters the engine cylinder through the fuel pipe.

The level of air density in the system depends on the area of the open air damper. The wider the damper is open, the greater the fuel consumption and power.

Simply put, carburetor adjustment

on a lawn mower - creating an optimal fuel mixture due to the correct air supply.

Signs of imbalance

Carburetor adjustment must be carried out at the time of manufacture of the device. As a rule, owners become aware of the need for self-regulation of the fuel supply after serious failures, during the correction of which the module was removed and, for example, cleaned.

Symptoms of a malfunction in the settings are as follows:

It starts but the engine stops immediately. Because the engine can only run when supplied with a certain amount of gasoline, if the fuel is too "bad", i.e. When the feed channel is blocked, the motor will stop;
Too high fuel consumption, too much exhaust gases. The result of incomplete combustion of the mixture. In this case, on the contrary, there is too much fuel, and the mixture is too thick.

Do-it-yourself lawn mowing carburetor adjustment

The module configuration is not repairable and no spare parts are required. In this case, a gas trimmer carburetor repair kit is not required.

There are three screws for debugging:

L. Regulated in the first place, as it is responsible for the supply of fuel at low speeds;
H. Responsible for the supply of gasoline at high speeds, as well as for fuel consumption and temperature;
T. With its help, a non-working setting is carried out.

As a rule, there are options, this is a Chinese carburetor gasoline scraper, when there is only one screw left on the body for adjustment. To set idle speed. This does not mean that the module is configured automatically. This means that even repairs such as debugging will be difficult to perform. On the picture. Chinese brush carburetor adjustment.

The module is installed only when the engine is warming up: the device first turns on for 10 minutes. If the mower spins at idle, start the adjustment immediately: turn the screw T anti-clockwise until the rotation stops.
Adjustment starts with screw L. The screw rotates left and right until it finds its position at which the idle speed reaches its maximum.
Then turn the screw counterclockwise. This will be his job.
Idle speed should be adjusted by turning counterclockwise to increase speed and decrease clockwise. Its setting is to achieve a mode in which a sufficient number of revolutions are performed before the mower begins to rotate. In this case, the engine should work stably in different positions.
The screw position L is determined last. At maximum speeds, the trimmer should not operate for more than 10 seconds. The throttle opens, the screw rotates clockwise, very slowly, until a decrease in speed is heard.
The propeller then also rotates slowly counterclockwise until the motor starts to malfunction. The screw then turns clockwise until the engine starts to run normally again.

READ Trimmer Handle Assembly

If you have a blood pressure monitor, and if the recommended speed is indicated in the product data sheet, the correction can be made more accurate, focusing not on the ear, but on the readings of the device.

Adjusting the brush cutter carburetor in the video is done by ear.

to the post "Adjustment and repair of the gasoline brush carburetor"

Dmitry Pavlovich 04.07.2016

Please explain. In section 5 adjust screw L. Error? Should screw A be read? Thank you

Tell me the initial position of the screws HL LA

PLEASE PREVIOUS POSITION

Tell me the initial position of the screws HL LA

Thank you very much for the accelerator video, and I don't know, the defect is very important and creates a huge problem that almost everyone is silent about. BRAVO….

Possibly a tachometer. It's a speedometer, not a tonometer. Blood pressure meter.

And I have L, H, LA, is that LA instead of T?

The heart of any chainsaw is a two-stroke internal combustion engine.

The trimmer is not used for complex appliances, so most of them are floor.

Reliable and accurate mechanical instructions must be acquired.

Gone are the days of Soviet agro-industrial gigantism. They did a concert.

Motoblock. This is an economical tractor option for small jobs.

In order to make a do-it-yourself harrow type nozzle, in addition to bodies.

Source

Basic problems

Malfunctions of the carburetor of a lawn mower or trimmer, despite the relative ease of their elimination, sometimes require a long search by elimination. The main reasons are:

unsatisfactory quality of gasoline cleaning;
clogged air filter;
accumulation of deposits and soot in the compartments and passages of the carburetor.

Each problem has its own causes.

Fuel supercharger malfunction

The most recurring failure is wear, membrane rupture. As a result, its non-adherence. Fuel passages are not sealed at certain stages of the engine cycle. The reasons here are:

you have been working on a lawn mower or trimmer for too long without a break;
refueled low-quality fuel;
exhaust gases enter the impulse channel.

A deformed membrane is fraught with several bad consequences:

there is not enough gasoline or oxygen in the combustible mixture created;
the engine starts after 10 or more unsuccessful attempts;
the engine knocks, clicks during operation, etc .;
the working piston is deformed.

Strainer blockage

The reasons for the clogging of the strainer are poor-quality fuel cleaning, damage to the hose and / or injection head.

Adjustment lever failure

The wear of the contact face of the lever is a consequence of not completely purified fuel, into which grains of sand or particles of clay, metal or other inclusions that are insoluble in liquid hydrocarbons have fallen. There is a problem with fuel injection, the engine without load functions intermittently.

Inlet needle damaged

The inlet needle breaks due to the presence of metal and stone particles in gasoline. As a result, the seat of the inlet needle does not fit snugly against it, the fuel mixture flows. There is too much air in the combustible mixture created by the carburetor, which can cause the engine to “sneeze” during operation. Finally, the needle may stop due to low-quality gasoline, or the unit has been idle for a long time.

Clogging of the adjustment space

Deposits may accumulate in the control chamber. The needle does not completely close the hole, and a lot of gasoline enters the fuel chamber - the engine overflows it, and possibly fills the spark plugs. Because of this, the gasoline-air mixture contains an increased amount of gasoline vapors. The efficiency drops noticeably.

Adjustment diaphragm defective

The membrane is often deformed (sometimes torn) due to the continuous operation of the lawn mower or trimmer for several hours. If you abuse this "shock" mode of operation, membrane damage occurs more often. New breakdowns will fall like from a cornucopia:

the piston will break;
the number of unsuccessful attempts to start the engine will increase dramatically;
the fuel mixture will contain too little gasoline;
useful (thermal) power will drop sharply.

Inlet control lever stuck

Jamming of the adjusting lever is a consequence of its incorrect installation, accidental bending. The contact face will be in the wrong position. This will disrupt the additional injection of gasoline.

The damper is worn out

The throttle and damper become unusable due to the entry of dust, metal particles, etc. with the air stream. Damaged dampers are similar to parts that have been sandblasted. Due to the wear of the dampers, the efficiency of the motor decreases, breakdowns are detected. The piston and cylinder wear out.

In some cases, this filter is simply not suitable for your model of lawn mower or trimmer. In the end, the motor shaft will suffer - its pieces fall into the engine channels, causing the piston to be broken.

Carburetor cannot be adjusted

The springs on the adjusting screws are to blame for the fact that the adjustment is too rough (it is not possible to accurately set the parameters). The manufacturer of a brushcutter or trimmer can supply unnecessarily thick and stiff springs. You can find others either in workshops where such equipment is repaired, or purchased from any dealer or official representative of the company that released the motor for your trimmer or mechanical scythe.

primer broke

The primer is a manual mini-pump for forced pumping of fuel into the carburetor. For a successful start of the engine, it may be necessary to pump up 20 ml of gasoline manually.

Carburetor device

The benzokosa (motokosa) contains a base - an aluminum body, in which the rest of the parts are placed, working smoothly as a whole. The carburetor body has a diffuser - a stroke with internal channels through which air is pumped.

The channels branching off from the diffuser stroke deliver fuel, with which the injected air is mixed, entraining gasoline vapors. Outside the main compartment of the carburetor are placed:

jets;
fuel mini-pump;
unit that regulates the mixing of fuel with air.

The latter forms the very explosive mixture ignited in the combustion chamber of the carburetor.

Husqvarna carburetor adjustment

Before adjusting the Husqvarna, do maintenance on the trimmer (wash the lawn mower and engine, replace the spark plug, fix minor defects).

Be sure to wash the foam element of the air filter. Wash element in warm soapy water, then wring out and dry (or replace if old or damaged).

Note: If you adjust a Husqvarna carburetor with a dirty air filter, the fuel mixture will become much leaner after cleaning the air filter (which can lead to poor performance or even engine failure). Install a trimmer head with a cord of the maximum allowable diameter and standard length (up to the cutting blade in the additional protection) to put a load on the engine while adjusting the high speed screw of the Husqvarna carburetor. Start the lawn mower according to the Husqvarna Manual and warm up for 10 minutes (if the trimmer head rotates at idle, then the idle screw, i.e.

lower, must be turned counterclockwise until the rotation of the trimmer head stops). Carefully turn both needles (right and left) to the middle position between fully screwed in and fully screwed in (do not turn by the stop!, this may damage the Husqvarna engine)

There are three adjusting screws for adjusting the Husqvarna carburetor: right, left and bottom.

1) Right screw L - adjusts the richness of the low speed mixture (adjusted first): Find the maximum idle speed by slowly turning the right screw to the right and left. Then turn this screw ¼ turn counterclockwise. Note: From the Husqvarna factory, the right screw has been fully out (0.5 turn). He is now looking at 11 o'clock. 2) Bottom screw T - Husqvarna engine idle adjustment (if necessary): turning the screw clockwise increases the idle speed, counterclockwise decreases it.

Idle speed adjustment is considered correct when:

A cold engine runs steadily at idle.
A hot engine does not idle too high.
Before the trimmer head begins to rotate, there is a sufficient reserve of revolutions.
The engine runs steadily in any position (for example, when the knife is sharply lowered).

Note: From the factory (Husqvarna) the idle screw from fully screwed in was 8 full turns and "2 o'clock" (it still is). The recommended idle speed for the engine of the Husqvarna lawn mower is 2,900 rpm.3) The left screw H - adjusts the enrichment of the high-speed mixture (adjusted last). It regulates maximum speed, engine power, temperature and fuel consumption.

Note: The Husqvarna engine must not be run at full speed for more than 10 seconds!

Fully throttle (give full throttle) and slowly turn the left propeller clockwise until the Husqvarna engine speed is reduced (by ear).
Then turn the left screw very slowly counterclockwise until the engine starts to run rough.
Then turn the propeller slowly back a short distance clockwise until the Husqvarna engine runs smoothly.

This completes the Husqvarna adjustment.

Note: The recommended maximum speed for the Husqvarna engine is 11,500 rpm. The maximum output power of the engine of the Husqvarna 333R brushcutter is 1.6 kW (2.1 hp) at 8,400 rpm.

Note: On a new Husqvarna trimmer from the factory (Husqvarna), the left screw was completely out (0.5 turn) and blocked (filled) with hard plastic, which I drilled out after the warranty expired. Now the left screw (as well as the right one) is facing approximately 11 o'clock.

Checking the correct setting of the Husqvarna carburetor

The engine picks up speed quickly, smoothly and confidently, and quads a little at maximum speed, the T-35 trimmer head should not rotate at idle.

Fine tune the carburetor

If the engine starts, but stalls, then the idle screw must be adjusted. If the speed is high - unscrew the screw, closing the air damper.

In the event that the revolutions, on the contrary, are small, then we tighten the screw, opening the air damper. "Playing" with this screw, you can achieve optimal parameters for the engine to idle.

If the engine stalls directly during operation (when you mow the grass), then you need to re-adjust the gasoline supply screw. We unscrew or tighten this screw until we achieve the desired result.

Reference. Read to understand what you are doing!

The desired composition (quality) of the air-fuel mixture is adjusted (changed) by turning the screws for adjusting the fuel supply to the intake air stream (right and left). The amount of mixture entering the cylinder is controlled by the throttle valve. If they are turned clockwise, the mixture sucked into the cylinder becomes leaner (less fuel in the air / fuel ratio) and the engine speed increases, while the Husqvarna engine runs softer (weakly picks up speed) and power drops dramatically. In addition, having increased speed, less oil enters the cylinder on a lean mixture with gasoline (worse lubrication) and so you can screw up the engine. Well, the trimmer will start badly. If the screws are turned counterclockwise, the mixture sucked into the cylinder is enriched (more fuel in the air / fuel ratio) and the engine speed decreases, while at low speeds more gasoline and oil enter the cylinder (better traction, better lubrication), but the Husqvarna engine “unwinds” poorly (poorly gains momentum) and more soot forms in the cylinder!

Carbon regulation

Wash the air filter before adjusting the carburetor. It is recommended to rinse every 10 hours. After that, you can start setting up. The example photo shows the carburetor of the PRORAB-8406 petrol trimmer. The numbers indicate the adjustment screws that we will use.

PRORAB-8406 Carburetor Adjustment Screws

Purpose of adjusting screws:

Screw for adjusting the fuel mixture.
Idle adjusting screw.
The screw limits the maximum speed.

Run the brush and wait for it to warm up.

Fuel regulation

Start slowly tightening the propeller that regulates the fuel mixture until the engine stalls or freezes if you haven't caught the moment. Then loosen the screw a quarter of a turn if the motor is not running, or a half turn if it is not running. Start the stopped engine. Check by opening the throttle to see how the engine accelerates. Continue backing out screw #1 a quarter of a turn until the engine begins to steadily pick up increased speed when gas is applied. This will be the moment of the most economical stable operation of the engine. On the PRORAB-8406 gas trimmer, the adjusting screws are turned clockwise and unscrewed. Counter-clockwise, some other brands of brush cutter may be the other way around.

READ How to Wind Line on a Gasoline Trimmer Properly

Idle adjustment

Let's move on to the low speed setting. Screw #2 restricts reverse movement of the throttle lever. Wrapping it, we increase the idle speed, unscrew it, reduce it. Adjust so that the motor runs confidently at low rpm and even a little faster (for a better start), but so that the spool of line or knife does not spin and there is ample headroom before you start to spin. If the engine does not start well, increase the idle speed anyway.

Maximum speed limit

After adjusting the fuel mixture and low speed, check how the hedge trimmer motor works at maximum speed. If necessary, limit the maximum speed to the required level using the hollow screw No. 3. Loosen the locknut and tighten it to decrease the maximum speed or loosen it to increase it. Tighten the nut after adjustment. Setting the maximum speed is necessary to protect the trimmer motor from overheating and the ability to use the key lock to reduce right hand fatigue.

You may need to adjust the carburetor trim later. For example, if the engine starts to rev poorly when running at full load, back off screw #1 another quarter turn. If starting is difficult, increase idle speed. Weather conditions and the quality of the fuel mixture can affect the performance of the hedge trimmers. Vibrating propellers themselves can also tip over due to vibration.

Tips for repairing a gas trimmer carburetor

Regardless of the manufacturer, there is a factory defect in the carburetor parts of the lawn mower.

For example, the tuning technique described above may not give positive results if the mixture screw spring has an excessively large number of turns and, as a result, the optimum reduction in the level of gasoline supplied cannot be achieved. To eliminate this, you can shorten the spring a little yourself or purchase a new one in accordance with the instruction manual.

Many owners of lawn mowers follow the recommendations for preparing the fuel mixture indicated there when buying oil.

So, often the information on mixing gasoline with oil indicated on the bank differs from the instructions in the trimmer passport. As a result, black deposits can quickly form on the spark plug, which leads to a drop in power and increased fuel consumption. Therefore, when preparing the working mixture, the recommendations specified in the instruction manual should be followed. In most cases, the ratio for a run-in internal combustion engine is 1:25. It is worth noting that many tool owners prefer to prepare fuel "by eye", which will certainly lead to rapid wear of the piston braid in the event of a decrease in the portion of oil and the formation of soot on the spark plug with an increased amount of lubricating fluid.

The tips correctly followed above on setting up the trimmer carburetor will help to avoid not only engine overheating, increased fuel consumption, but also significantly increase the life of other parts and assemblies of the tool

Pay attention to the operation of the lawn mower in all modes and carry out scheduled maintenance and repair of the tool in time.

From personal experience

Benzokosa or trimmer

Trimmer. This is a broader concept than a gasoline scythe, because it can also be electric. Gas trimmer and brush. It is the same.

Some authors claim that the trimmer is a weaker tool compared to the more powerful hedge trimmers that can be used to mow bushes. Personally, I have a tool with a maximum power of 1.7 kW, and I can mow a small bush up to 10 mm thick, as indicated in the instructions. The user manual is called "Petrol Trimmer."

Fuel mixture ratio

I read somewhere that if the instructions for the motorcycle and the oil may indicate different proportions of the fuel mixture, you should use the proportion indicated in the manual.

This has been the case for a long time. Excess oil flowed from the engine into the gas tank, and soot constantly formed on the spark plug, because the instructions indicated the ratio for running the engine at 1:25 and a canister. 1:50. Has stopped. The spark plug continued to burn, but with less intensity (the carburetor had not yet been adjusted).

Until now, some users of gasoline tools determine the proportion of the fuel mixture "by eye". If the amount of oil is underestimated during the preparation of the mixture, after a while, immediately after starting the engine, a strange sound may appear, gradually disappearing during warm-up, and the engine stops abruptly. Continued operation of the trimmer in this mode will result in its failure.

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cleaning candles

In the worst of times with a non-adjustable carburetor trimmer, the engine would stop starting after every tank of fuel was used. And only having cleared the candles of soot, we could continue our work.

Fine sandpaper was used to clean the electrodes, and a thin bent-end staple was used to clean the space between the insulator and the case. First, the electrodes were wiped from large dirt with a rag, then they were cleaned with sandpaper. After that, the candle was dipped into diesel fuel, and the wetted soot was scraped off with a paper clip from the surfaces of the insulator, the inside of the case, and between them. The candle was then immersed several times in diesel fuel, which was then shaken off along with impurities. Sometimes the paperclip and rinse procedure is repeated. After that, the candle was wiped dry and were ready for further use.

It is unlikely that one tank of fuel with an untuned carburetor can be used up in less than 10 minutes. This was tested in practice when the trimmer was started and worked at high speeds with maximum fuel supply (the adjusting screw was unscrewed much more often than usual).

Source

Gas scythes, like all gas-powered garden tools, are not easy to maintain. You can and should repair, tune yourself. For example, self-management of a carburetor with a homemade brush. A matter of five minutes.

The brush cutter carburetor is a node in the power system. In it, as in any carburetors, the process of mixing air and fuel (gasoline) takes place for subsequent supply to the engine cylinders.

Model description

The above equipment option costs 13,490 rubles. It is a premium device. With it, you can take care of the territory on a large suburban area. The equipment lends itself to young and ancient grass, reeds and weeds, as well as young shrubbery.

The Calm FS 55 lawn mower, reviews of which you can read below, has a powerful 1 liter engine. With. The device is amazingly suitable for use in a suburban area or cottage. In one pass, you can mow 420 mm of grass in width. This device is suitable for hardware lawn processing, grass mowing and allows you to even walk along fences, process narrow areas and areas near flower beds. The tank holds 0.33 liters of fuel, which will be enough for uninterrupted operation for half an hour.

Elimination Methods

The list of upcoming work with the engine may be as follows:

replacement of the fuel pump;
disassembly and washing of the strainer;
replacement of the adjusting lever;
it is also necessary to clean the adjustment space;
replacement of the membrane (or the entire block where this membrane is located);
adjustment of intake, exhaust and needle valves;
damper replacement;
cleaning of fuel channels and diffuser;
replacement of screw springs;
primer change.

Not all of these jobs can be completed. It often turns out that many of them are not needed if a specific malfunction is immediately detected.

The device of the lawn mower

The device of the Stihl FS 55 lawn mower should be clear to you if you plan to operate the equipment, and even more so to repair it. The internal combustion engine in this unit is almost the same as in a chainsaw. But the last tire is fixed to the motor gearbox with a long tubular rod. A shaft is placed inside, which transmits torque from the motor to the working tool. This design is hung on a belt that is thrown over the shoulder. This allows you to hold the tool on weight, which is important with the sensitive mass of the chainsaw.

A handle is fixed to the rod of the unit; with it, you can move the end of the rod with working equipment. The Calm FS 55 lawn mower, the annotation for the repair of which is presented in the article, has a protective shield in the form of a casing on the human side, which eliminates injuries during operation. The instrument itself is a round drum, on both sides of which a thick fishing line comes out of the holes. Carburetor and chainsaw adjustment When the drum spins, the fishing line is pulled under the action of centrifugal force and hits the grass, cutting it.

The Calm FS 55 lawn mower, the technical properties of which will be presented to your attention below, has a quick-wearing nylon fishing line. Features motokosa Stihl fs 38, adjustment of the carburetor of lawn mowers Stihl fs 38. It is sometimes updated by the method of unwinding the coil, which is located inside the drum.

Video: How You Can Rinse a Carburetor on a Home Trimmer

Its location may vary depending on the trimmer model, but is usually located on the side of the device under the protective cover.

The case is attached either with a bolt or with a latch, which is very easy to open to remove the contents. The filter itself can be made in the form of a ring or plate made of foam, felt, fleece.

If you mow an average of 1-2 times a week, a replacement at least once a year will suffice. For more intensive use, inspection and replacement should be performed more frequently.

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