Husqvarna petrol mower does not work at full capacity. Husqvarna trimmer fuel system

Petrol mowers, like all petrol-powered garden tools, are not difficult to maintain equipment. You can and should repair and configure yourself. For example, adjusting the carburetor of a lawn mower with your own hands is a matter of five minutes.

The carburetor from a lawn mower is a component in the power system. In it, like any carburetors, the process of mixing air and fuel (gasoline) takes place for further 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 adjusted.

Main problems and malfunctions of the carburetor.

Mesh filter. There are usually only two problems with this element:

Blockage.
Breaking.

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

If there is visible damage to the mesh filter, you must install a new one. There may also be damage to the fuel supply pipe (during repairs, it is practiced to check this element).

In most cases, the carburetor starter does not function due to blockages. Acetone or the same gasoline should be used for washing.

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

The throttle body, joints of carburetor parts, intake or exhaust pipes - all of these parts are subject to depressurization. You can definitely check it in a primitive way - spread soap foam on the problem area.

The structure of a lawn mower carburetor

The basis of the carburetor is an aluminum body. It contains a diffuser (a hole with internal contours). Air is forced through this hole. The oxygen (air) supply rate depends on the cross-section (pass hole) of the diffuser.

The diffuser is equipped with fuel channels. Fuel is drawn from them using an air flow.

Install externally on the carburetor:

fuel pump;
jet system;
fuel-air mixture adjustment system;

The operating principle of a lawn mower carburetor

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

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

Step-by-step operation of the device:

Air supply into a tube with an air baffle (damper). The partition regulates the intensity of the air flow.
The fuel supply system is necessarily narrowed with a diffuser to increase the flow rate.
Gasoline through the float chamber and the nozzle tube with a narrowing. A chamber with a float regulates the temporary volume of gasoline. In the float chamber the pressure level is neutral, and in the tube with a narrowing it is already low. Due to the pressure difference, fuel penetrates through the nozzle.
Accelerating air flow promotes 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 throttle is open, the greater the fuel consumption and power.

Simply put, adjusting the carburetor on a lawn mower is creating an optimal fuel mixture due to the correct air supply.

How to adjust the carburetor on a lawn mower

Before adjustment, the filters must be thoroughly cleaned according to maintenance in the instructions.

Further adjustment of the lawn mower carburetor is done with your own hands using 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 turn counterclockwise.

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

clockwise – increase;
counterclockwise – decrease.

For correct adjustment idle speed characteristic:

stable operation of a cold engine;
not over-revving a hot engine;
there is a large reserve of revolutions for the trimmer head;
stable operation of the engine when changing position (sudden raising or lowering of the knife).

Left (H)– adjusting the mixture at high speeds. (The screw is adjusted last).

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

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

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

Correctly adjusting the carburetor with your own hands in this case means combustion of the fuel mixture without residue; the color of the spark plug should be light brown.

Adjusting the carburetor of a brush cutter in practice - video

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

It is almost impossible to cover all types of carburetors produced by gas trimmer manufacturers. But, since the design of this module, as well as its operating principle is largely similar between different models, then we can make a generalized description of the processes occurring in the carburetor. This information will allow the user to understand the principles of operation of the device, troubleshoot problems and operate it correctly.

The basis of the trimmer carburetor is one-piece aluminum body. Below is a diagram of this block.

At the bottom of it there is a diffuser, which is also called Venturi nozzle(18). Air is sucked through this nozzle by a motor.

The smaller this hole is, the faster the air flows, and the higher the level of its rarefaction will be in the area with the smallest diameter.

At the top of the diffuser there are fuel channels(11,12). Air flows through these channels and draws in gasoline. The fuel pump itself, the jets and the system used to regulate the flow of the fuel-air mixture can be built-in or installed externally.

Throttle valve(9) regulates the amount of air sucked into the carburetor. Its amount affects the power that the engine develops. The flap (7) is used for cold starting. It must be closed if you are going to start the unit. After the engine has started, it must be opened, otherwise the engine will immediately stall.

Pulse channel(1) connects the impulse chamber of the pump to the engine crankcase, namely, to its internal volume. The piston located in the cylinder, performing reciprocating movements, consistently changes the pressure in the crankcase (vacuum or increase in pressure). Pressure differences cause the membrane (4) to move. Therefore, the operation of the pump is synchronized with the operation of the engine.

The suction of gasoline from the tank occurs precisely with the participation membranes(4). Gasoline enters the carburetor through fitting (2). Further, its path lies through the inlet valve (3), exhaust valve (5), through the mesh filter (6), fuel channel (10), passes the needle (14) and fills the chamber (16), which has a control membrane (18) .

The valve (14) is connected to the membrane (18) via a lever (17). The cavity, which is located below the membrane, is connected to atmospheric air through the hole (19).

The device operates as follows.

A vacuum is created in the diffuser during the suction stroke. This fact causes air leaks. The position of the throttle valve (9) determines the amount of air entering the carburetor chamber, as well as the engine power and the number of revolutions.
At this time, fuel is sucked from the chamber (16) through the jets (11,12), after which it is mixed with the flowing air. Gasoline, mixing with air, begins to atomize. Thus, it is created air-fuel mixture.
The finished mixture enters the cylinder, where it is compressed by a rising piston and ignites at its top point from a spark generated by the spark plugs.
Since the volume under the control membrane (18) is connected to atmospheric air through the channel (19), the membrane goes up, opening the valve (14) through the lever (17). After opening the valve (14), a new portion of fuel enters the chamber (16).
Once the chamber (16) is filled, the membrane (18) returns to its original position and the valve (14) closes.

Further, when the motor is running, all the above processes are repeated. To adjust the amount of fuel entering the diffuser through the jets, a screw (13) is used. A screw (15) is also used to adjust the idle speed. When the regulators are unscrewed, the fuel mixture becomes richer, and when the regulators are tightened, the mixture becomes leaner. Also in some carburetor models you can adjust the engine idle speed quantity regulator. It is usually located on the outside and, when tightened, rests against a lever mounted on the throttle valve axis.

Thus, using 3 adjusting screws, you can achieve maximum engine performance, as well as configure its smooth operation at any temperature environment, and even in mountainous areas.

Common carburetor malfunctions

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 a carburetor yourself. Listed below typical faults brush cutter carburetor.

Fuel pump problems

A common malfunction that plagues the fuel pump is deformation of the pump membrane. For this reason, it does not seal properly and the pump channels do not seal.

The reasons for membrane deformation may be the following:

long-term trimmer operation;
use of unsuitable fuel;
entry of gases into the pulse channel.

As a result, damage to the membrane reduces pump performance, and as a consequence:

the combustible mixture becomes depleted;
it is difficult to start the engine;
there are interruptions in the operation of the motor;
the piston is damaged.

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

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

Strainer clogged

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

To eliminate the problem, you will need to thoroughly clean and rinse the strainer. Also recommended blow with compressed air all holes in the trimmer carburetor body.

The adjustment lever is faulty

This breakdown occurs when the contact surface of the lever wears out.

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

Worn inlet needle

The inlet needle fails, usually due to the presence of abrasive particles in the fuel fluid.

As a result:

the tightness of the inlet needle seat is disrupted;
leakage of the flammable mixture appears;
Engine malfunctions appear due to over-enrichment of the fuel mixture.

Also, the inlet needle may simply jam.

A stuck inlet needle may cause presence of dirt in the fuel, or a long downtime of the device without operation.

Clogged adjustment cavity

If dirt accumulates in the adjustment cavity, the inlet needle cannot tightly close the hole and a lot of fuel pours into the chamber.

This causes fuel re-enrichment, and the engine starts to work incorrectly. It is necessary to disassemble the carburetor and clean the cavity of the adjusting membrane.

Deformation of the control membrane

The membrane may be subject to deformation when long work unit and when using aggressive fuel.

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

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

Intake control lever problem

This problem can occur if the adjustment lever is not installed correctly or if it is bent before installation. As a result, the contact surface takes an incorrect position, which disrupts the additional fuel supply.

Damper wear

The throttle and choke valves mostly wear out due to abrasive particles in the air. Defective dampers look as if they have been sandblasted.

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

Worn throttle and choke shaft

The air and throttle valve shaft may wear out due to 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 hit 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 (functional) one. The filter must be washed in soapy water and dried.

When to make adjustments

Carburetor adjustment is necessary in the following cases:

the new engine was run-in (4-5 liters of fuel mixture were used);
the composition of the fuel has changed (brand of oil and gasoline);
the weather changed (it became hot, cold);
air rarefaction has changed (applies to mountainous areas);
after long-term storage;
the load on the engine has increased (after changing tools, etc.);
due to vibration, the adjustment screws spontaneously unscrewed;
Fuel consumption has increased, the carburetor is overflowing with fuel;
carbon deposits quickly appear on the electrodes of the spark plug (even though the fuel mixture is prepared correctly);
the engine starts and immediately stalls or picks up speed poorly;
no gasoline enters the cylinder;
a large amount of exhaust gases.

How to make the adjustment correctly

Before you start adjusting the trimmer carburetor, you must do the following:

flush the engine;
replace or clean the spark plug;
replace with 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 thoroughly).

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

If at idle motor, have you noticed that cutting tool rotates, which means it is necessary to reduce engine speed. This is done using the lower idle speed control, often marked with the letter “T”. The picture below shows the placement of the controls on a Husqvarna trimmer.

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 comes to a complete stop.

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

Right knob L adjusts the level of enrichment of the fuel mixture at low speeds. It needs to be adjusted first. Achieve maximum idle speed. This is done using the L control, turning it left and right. After finding the point of maximum speed, return the regulator half a turn to the left (counterclockwise).
Lower adjuster T (LA) used to adjust idle speed. By turning it to the left, the engine speed will begin to decrease, and when turning the regulator to the right, the engine speed will increase.
Left Knob 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 operate at full speed for more than 10 seconds, it may fail.

To eliminate this nuisance, adjustment will be required. With the engine running, give full throttle, then turn the “H” control to the right until the speed begins to decrease. After this, the “H” regulator must be slowly turned to the left until you hear uneven engine operation. Then turn the “H” control to the right until you hear the motor running smoothly.

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

Adjustment lawn mower carburetor you can do it yourself

Petrol mowers, like all petrol tools for the garden, are not difficult to maintain equipment. It is possible and necessary to repair and configure without the help of others. For example, adjusting the carburetor of a lawn mower with your own hands– it’s a matter of 5 minutes.

The carburetor from a lawn mower is a component in the power system. Carburetor adjustment That's it for Husqvarna adjustment. Well, there will be a trimmer. In it, like all carburetors, the process of mixing air and fuel (gasoline) takes place for subsequent 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 adjusted.

Main problems and malfunctions of the carburetor.

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

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

If there is 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).

In most cases, the carburetor starter does not work due to blockages. You should use acetone or the same gasoline for washing.

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

The throttle body, joints of carburetor parts, intake or exhaust pipes - all of these parts are subject to depressurization. You can probably check simple method– Spread the problem area with soap foam.

The structure of a lawn mower carburetor

The base of the lawnmower carburetor is a duralumin body. It contains a diffuser (a hole with internal contours). Air is forced through this hole. The oxygen (air) supply rate depends on the cross-section (pass hole) of the diffuser.

The diffuser is equipped with fuel channels. Fuel is drawn from them using an air flow.

Install externally on the carburetor:

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

The operating principle of a lawn mower carburetor

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

Adjustment carburetor brush cutters Husqvarna 125, 128

How to adjust carburetor brush cutters Husqvarna 125, 128 (without tachometer) Part number: 5450818-48.

Husqvarna 125R carburetor adjustment without tachometer (temporary solution)

How to adjust carburetor, if you need to work, but a service with a tachometer is too far away.

Step-by-step operation of the device:

Air supply into a tube with an air baffle (damper). The partition regulates the intensity of the air flow.
The fuel supply system is certainly narrowed by the mixer to speed up the flow.
Gasoline through the float chamber and the nozzle tube with a narrowing. A chamber with a float regulates the temporary volume of gasoline. In the float chamber the pressure level is neutral, but in the tube with a narrowing it is already small. Due to the pressure difference, fuel leaks through the nozzle.
Acceleration of the air flow promotes the transfer of fuel (gasoline) and its atomization. Ultimately, an air-fuel mixture of the required 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, adjustment carburetor on a lawn mower - creating a good fuel consistency due to correct air supply.

How to adjust the carburetor on a lawn mower

Before adjustment, you need to carefully clean the filters according to the technical maintenance instructions.

Upcoming setup do-it-yourself lawn mower carburetor made with adjusting screws. There are three in total:

Right (L)– adjusting the fuel consistency for low speeds.

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

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

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

clockwise – increase;
counterclockwise – decrease.

For correct idle speed adjustment it is typical:

stable operation of a cool motor;
not over-revving a hot engine;
there is a large supply of revolutions for the trimmer head;
stable operation of the motor when changing position (sudden raising or lowering of the knife).

Left (H)– consistency adjustment at high speeds. (The screw is adjusted last).

The overall adjustment of 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:

Open the throttle to full, and at the same time give full throttle. Turn the screw clockwise until the speed drops (in this case, use your ear).
Turn the screw as slowly as possible counterclockwise until the motor runs unevenly.
Then turn back just a little, barely hearing measured, even work.
For a more pleasant implementation of abilities, it is more convenient to see the work of an experienced user:

It’s interesting that based on the creator’s beliefs video, the setting (its correctness) is determined by the color of the spark plug, and not just by the speed and stability of the engine.

Faithful carburetor adjustment with your own hands in this case - combustion of the fuel mixture without residue, the color of the candle should be light brown.

Trimmer. How to properly start a cold trimmer engine Created by: Vasilii Ivanovih Posted: Feb 11 2016 Views: 56,692 Liked: 146 Disliked: 268 Trimmer. How to properly start a cool trimmer engine. Our client is left with the subtleties and tricks of starting a cool trimmer. The trimmer starts up great if you...