How to set up a carburetor on a Stihl lawn mower

Table of Contents:

When to adjust the Stihl 180 carburetor

First, it is worth deciding why it may even be necessary to adjust and repair the stihl ms 180 carburetor. So, this must be done in the following cases:

  • if the chainsaw does not keep idling;
  • repairs may be required if the saw does not start;
  • there is a loss of power;
  • increased fuel consumption;
  • the chainsaw does not develop maximum speed.
  • stalls when accelerating.

This list can be continued for a long time, but we have identified the main reasons. Before proceeding with the adjustment, you need to know what are the main parts of the carburetor on the Stihl 180 chainsaw, and who makes it.

Frequent Stihl carburetor breakdown and how to avoid it

A common reason for the failure of a carburetor on a Stihl chainsaw is a sticking valve in the nozzle. The reason for sticking is a violation of the storage of the chainsaw, or rather the instructions of the manufacturer Stihl 180 for proper preparation for storage.

As follows from the instructions, before long-term storage, it is necessary to drain the fuel from the tank, then start the saw and burn the gasoline from the carburetor. Failure to comply with this elementary rule entails the following consequences. The forsknui valve, being in direct contact with the fuel, sticks to the body, since the gasoline evaporates little by little and only sticky oil remains. It is impossible to replace the nozzle, since they are not in the repair kit, you can only try to knock it out and rinse it, which is not always possible to do without damaging the nozzle.

Nozzle

The fuel injector is mounted in the carburetor body in such a way that it is a connecting link between the distribution chamber and the cavity in which the throttle valve is installed. Simultaneously with the fuel, air is supplied to the nozzle and an air mixture is formed. The nozzle has a check valve that blocks the flow of air in the reverse sequence, that is, from the throttle chamber to the distribution chamber.

Removal and installation algorithm

In cases where it is necessary to clean the Stihl 180 carburetor or disassemble it, you first need to remove the assembly from the chainsaw. This must be done in compliance with a certain algorithm of actions:

  • Put the protective cover for the chainsaw on the tire.
  • Remove the top cover of the chainsaw.
  • Remove the two nuts securing the air filter and carburetor.
  • Remove the air filter housing.
  • Disconnect the wire from the engine control lever.
  • Carefully remove the lever from its seat in the housing, at the same time disconnecting the air damper rod from it.
  • Pull the carburetor towards you and disconnect the fuel supply as well as the throttle rod.

To facilitate dismantling, you can additionally untwist the rear handle and disconnect the throttle rod first from it, and then only from the carburetor. This may be required, because without some experience, disconnecting the rod from the carburetor is quite problematic and it is easier to disassemble the handle first.

To install the part in place, follow the reverse order of the algorithm.

When removing and installing the chainsaw engine control lever, you should be extremely careful, since the seat on the saw body is the weak link of the saw, and very often inexperienced users break it.

Air damper

The carburetor choke is installed on the opposite side of the throttle and is responsible for starting a cold engine, it is controlled by the engine control lever. For a cold start, the air damper is completely closed, for normal operation, open.

carburetor, stihl, lawn, mower

Dismantling the carburetor Stihl 180

In order to purge, change gaskets or the needle valve, the carburetor must be disassembled. To do this, unscrew 4 screws on the expansion joint cover and one on the fuel pump.

Having opened the case, you should be extremely careful, because if debris gets into the inside of the carburetor, it will make its work impossible. The thickness of the channels in it is comparable to the thickness of a thread or even a human hair.

A video for repairing a Stihl 180 carburetor can be viewed below. In it, the master tells in detail about the problems and clearly demonstrates the entire repair process..

Stihl 180 carburetor device

So, the stihl ms 180 carburetor is developed and produced by a subsidiary of Stihl called Zama. Original carburetors, on their body have a company logo that guarantees product quality.

The nuances of adjusting the carburetor of the Stihl MS 250 chainsaw

You may have a question about how to adjust the carburetor on a Stihl chainsaw. First you need to decide when such a need arises. The described work may be required if the spark plug electrodes have changed color. When it turns out to be black, this indicates over-enrichment, while with a brick-gray color, you can be calm, since this is the norm. When a master notices a white bloom, then he can be sure that the mixture is depleted..

The main role in the adjustment is played by the upper screw, in the described model it is located closer to the muffler. If you follow the factory parameters, which you can find on the tool cover, then this screw must be unscrewed one turn, and then corrected. When unscrewing, the mixture will be enriched, while if the screw is screwed in, the mixture will be leaner, while less gasoline will enter the air-fuel mixture.

When carburetor adjustment is required

If it happens that the adjusting screws are loosened, then the carburetor should be adjusted. Other signs may indicate the need for these manipulations, among them:

  • breakage of the protective cap;
  • significant piston wear;
  • interruptions in the operation of the motor;
  • strong vibration;
  • no response from the engine when trying to start the tool;
  • increased fuel consumption;
  • strong exhaust.

Idling check

You should know how to adjust the carburetor on a Chinese chainsaw. In this case, another check is carried out at idle speed. Once the acceleration adjustment has been completed, it is necessary to bring the tool to idle. If you did everything correctly, the chain will remain stationary, and the motor will pick up speed in a short time when you press the accelerator.

You should also listen to the operation of the engine. The sound should be like a four-stroke unit. If you are thinking about how to properly tune the carburetor on a chainsaw, then you must make sure that the above conditions are met. If this is not the case, then the adjustment must be repeated, and the basic stage is omitted. You should not take to work if you do not have sufficient experience, because in this case, a misalignment of the unit may occur. When self-tuning is not possible, then stable work can be achieved by contacting professionals.

Final stage

Before adjusting the carburetor on a Husqvarna chainsaw, you need to find the third screw, which is marked with the letter “T”. Then the engine is warmed up for 10 minutes at medium speed. The third screw must be turned counterclockwise until the motor starts to run steadily. The chain must be stationary.

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If the engine stalls at idle, the screw should be turned clockwise. When the target moves, the screw is unscrewed back. If you are faced with the question of how to set up the carburetor on a chainsaw, the next step is to check how the engine works correctly at maximum speed when accelerating. It should be assumed that the engine is functioning correctly under acceleration if the accelerator is pressed to a maximum speed between 2800 and 15000. The screw marked “L” must be unscrewed to the left one eighth of a turn.

How to set up a carburetor on a chainsaw: recommendations

Chainsaw carburetor. this is one of the main components of this tool. He is responsible for the fuel supply. The efficiency and power of the equipment depends on how correctly this unit functions. Timely adjustments also ensure cost-effectiveness.

Before adjusting the carburetor on a chainsaw, you should know that adjustments to this part of the device are quite rare. As a rule, the factory setting is sufficient for normal operation. However, if more precise adjustment is required, then special screws can be used. Before starting such work, it is necessary to understand the subtleties and nuances of the process.

Specialist’s recommendations for working with the Druzhba chainsaw carburetor

Before adjusting the carburetor of the Druzhba chainsaw, you must carry out maintenance on the tool. It involves flushing the engine, cleaning the carburetor, replacing the spark plug, checking the chain tension, cleaning the air filter, warming up the engine and adjusting the idle speed. Once the screws “H” and “L” have been tightened all the way, they must be unscrewed one turn. This must be done when the chainsaw is muffled..

Then the tool is warmed up, full throttle is given, and the first of the mentioned screws rotates in such a way as to reach 14,000 revolutions per minute. The maximum speed should be held for 10 seconds or less.

By turning the last screw, ensure that the chain starts to move. Then the bolt is loosened a quarter turn counterclockwise. If after this the idle speed turned out to be not so stable, and the tool accelerates slowly, the screw under the designation “L” must be turned counterclockwise, only then the chainsaw will gain speed.

It is important to remember that the adjustment will not give results if air is sucked into the engine from the side. This can happen through:

  • accelerating pump;
  • carburetor;
  • a gasket under the carburetor;
  • crankshaft oil seals.

After completing the procedure, the engine of the instrument can be started by warming it up for 10 minutes. In this case, you can set the average speed. Then you can do the idle screw.

Basic adjustment step

First you need to use the rotational screws. They are wrapped clockwise all the way. Then turn it back one and a half turns.

Preliminary manipulations

In order to get to the carburetor, the bolts on the tool cover are unscrewed. The case must be opened and the foam rubber, as well as the parts of the air filter must be removed. Only now can you start adjusting. Before setting up the carburetor on a chainsaw, you should find out that the main task of these works is to change the quantity and quality of the air-fuel mixture that is pumped into the engine combustion chamber.

While working, you must follow certain rules, among them:

  • the chain must be directed to the side;
  • the equipment should be laid on a flat surface;
  • the cutting parts must be removed to a safe distance.

The first requirement is due to the need to avoid injury. If you are wondering how to set up a carburetor on a chainsaw, you should know that it is necessary to carry out these works using three screws. The first one controls the jet and is designated by the letter “H”. It is necessary to correct the maximum speed..

The second screw can be found under the letter “L”. This assembly is required to control the idle jet at low shaft speeds. Quite often, novice craftsmen ask themselves how to set up a carburetor on a Partner chainsaw. It denotes the third screw with the letter “T”. It is needed to correct the idle speed. The adjustment process is divided into stages:

  • base;
  • final.

The first is carried out with the engine off, while the second is carried out with a warm engine.

Throttle and choke shaft wear

The air and throttle shaft can wear out 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 cleaned air, the shaft wears out and can 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 flush the existing (serviceable) one. The filter must be washed in soapy water and dried.

How to adjust the carburetor on a lawn mower

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

The principle of operation of the carburetor lawn mowers

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

Stihl FS 55 Lawn Mower Carburetor Adjustment

Stihl FS 55 lawn mower carburetor adjustment Sadservice spare parts store sadservice.com.ua.

Fuel is sucked into the carburetor system by a pump (its membrane). Then it passes through the choke in the carburetor. The fluid then flows through the pump inlet and outlet valves. Filtered by the grid. Moves through the needle valve into the diaphragm chamber.

Clogged control cavity

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

How to clean, adjust, and fix common carburetor problems on a Stihl FS90 trimmer weedeater

This causes over-enrichment of the fuel and the engine starts to malfunction. It is necessary to disassemble the carburetor and clean the cavity of the control membrane.

Stihl FS 55 Lawn Mower Carburetor Adjustment

Stihl FS 55 lawn mower carburetor adjustment Sadservice spare parts store sadservice.com.ua.

Fuel is sucked into the carburetor system by a pump (its membrane). How to adjust the carburetor you were told correctly. Adjusting the carburetor trimmer Stihl fs 38 Then it goes through the union in the carburetor. How to adjust the carburetor of a gasoline lawn mower. How to adjust the carburetor to the carburetor from lawn mowers is a knot in the power system. Then the liquid moves through the inlet and outlet valves of the pump. Filtered by the grid. Moves through the needle valve into the diaphragm chamber.

Step-by-step operation of the device:

  • Air supply to a tube with an air baffle (damper). The baffle regulates the intensity of the air flow.
  • The fuel supply system is necessarily narrowed by the mixer to speed up the flow.
  • Gasoline through the float chamber and the nozzle tube with a constriction. A float chamber adjusts the temporary volume of gasoline. In the float chamber, the pressure level is neutral, and in the tube with a constriction it is already small. Due to the pressure drop, the fuel seeps through the jet.
  • The acceleration of the air flow facilitates the transfer of fuel (gasoline) and its atomization. Ultimately, 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 throttle is open, the greater the fuel consumption and power..

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

Lawn mowers carburetor device

The basis of the carburetor for lawn mowers is an aluminum body. It contains a diffuser (hole with inner contours). Air is blown through this hole. The flow rate of oxygen (air) depends on the cross-section (orifice) of the diffuser.

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

Outside the carburetor is installed:

  • fuel pump;
  • jet system;
  • a system for adjusting the mixture of fuel and air;

Principle of operation

A carburetor is a power system module in which liquid fuel and air are mixed before being fed into the engine cylinders. Mixing and flow are adjusted accordingly depending on the tool and its mode of operation..

The carburetor device for lawn mowers is the same for almost all cases. It belongs to the category of float devices. The latter provide stable parameters of ready-made mixtures.

The principle of the module is as follows.

  • Air enters the body of the air damper tube. The latter increases or decreases the air flow depending on its position..
  • In the area where the hole for the gasoline supply is formed, the tube has a narrowing – a diffuser. Here the flow rate increases.
  • Fuel from the float chamber is fed through the nozzle into the tube. The float level determines the amount of fuel supplied. Since the pressure in the chamber is normal, and in the tube it is low due to the greater rarefaction of the air, gasoline is sucked in through the nozzle.
  • The accelerated air flow picks up the fuel and atomizes it, forming an air-fuel mixture of the desired density.
  • The mixture is sucked into the cylinder through the pipeline.

The more open the air damper in the tube, the higher the density of the air flow, and, therefore, more fuel enters the cylinder. Adjusting the carburetor of lawn mowers is reduced to setting such a ratio of flaps, at which the density of the fuel mixture becomes optimal.

Adjustment and repair of the carburetor lawn mowers

The trimmer does not belong to complex household appliances, therefore, most of its breakdowns are mechanical in nature and are quite successfully eliminated with their own hands. Even if the engine fails for serious reasons – damage to the piston ring, for example, repairs are reduced to replacing a part.

But even with a relatively simple design, such a part of the device as a carburetor needs to be adjusted..

Signs of imbalance

Debugging the carburetor is mandatory during the manufacture of the device. As a rule, the owners will find out about the need to adjust the fuel supply with their own hands only after serious enough breakdowns, in the process of correcting which, the module was removed and, for example, cleaned.

Correct Way To Adjust Or Tune The Carburetor On A Weedeater / Grass Trimmer – Video

The following are the symptoms of a configuration failure:

  • starts, but the engine immediately stalls – since the engine can only work when a certain amount of gasoline is supplied, with too “lean” fuel, that is, blocking the supply channel, the engine will stop;
  • too high fuel consumption, a lot of 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 dense..

The carburetor for lawn mowers Stihl, Makita, Husqvarna and others is adjusted using the adjusting screws. Sometimes the reason for the malfunction is a violation of fixation – due to vibration or damage to the protective cap. Such a breakdown can be detected by simply trying to turn the screw slightly: if the fixation is not rigid, it is worth checking the setting.

Diy lawn mowers carburetor adjustment

Setting up the module does not apply to repair and replacement of spare parts is not required. In this case, the lawn mowers carburetor repair kit will not be needed..

Three screws are provided for debugging:

  • L – is regulated first, since it is responsible for supplying fuel at low speeds;
  • H – he is responsible for the supply of gasoline at high speeds, as well as for fuel consumption and temperature;
  • T – it is used to debug idle.

There are options, as a rule, this is the carburetor of a Chinese lawn mower, when only one screw remains on the body for debugging – for adjusting the idle speed. This does not mean that the module is configured automatically – it means that it will be difficult to carry out even such a type of repair as debugging. In the photo – adjusting the carburetor of a Chinese lawn mower.

  • The module is configured only when the engine is warm: for this, the device is pre-switched on for 10 minutes. If the mowing head rotates at idle speed, then the debugging is started immediately: turn the screw T counterclockwise until the rotation stops.
  • Adjustment begins with screw L. The screw is turned to the right and left until it is found such a position at which idle speed does not become maximum.
  • Then the screw is turned ¼ turn counterclockwise. This will be his working position..
  • Idle speed must be adjusted by turning counterclockwise to increase the number of revolutions and clockwise to decrease it. Its debugging consists in achieving such a mode in which a sufficient number of revolutions are made before the start of rotation of the mowing head. In this case, the engine must work stably at different positions.
  • The position of screw L is determined last – at maximum speed, the trimmer should not work for more than 10 seconds. The throttle opens, the screw turns clockwise, very slowly, until a decrease in the number of revolutions is audible.
  • Then, also slowly, the screw rotates counterclockwise until the motor starts to malfunction. Then the screw is turned back clockwise until the engine starts working normally again..

If there is a tanometer, and if the recommended rpm values ​​are indicated in the product passport, the correction can be made more accurate, focusing not on hearing, but on the readings of the device.

The adjustment of the carburetor of the lawn mowers in the video was carried out by ear.

8 comments on the entry “Adjustment and repair of the carburetor lawn mowers”

    Dmitry Pavlovich 07/04/2016

Please clarify. In the adjustment section p. 5, screw L – error? Should you read screw A? Thank you.

prompt the initial position of the screws H L LA

SHOW START POSITION

prompt the initial position of the screws H L LA

Thank you very much for the video about the accelerator and did not know, but the defect is very important and creates a huge problem that almost everyone is silent about. BRAVO….

Maybe all the same tachometer is a rpm meter, and not a tonometer blood pressure meter

and I have L, H, LA, it’s LA instead of T?

The video shows some kind of tightness, so you need to be able to chew snot.

Maximum speed limitation

After adjusting the fuel mixture and low speed, check how the lawn mower engine will run at maximum speed. If necessary, limit the maximum speed to the required level using the hollow screw. Loosen the locking nut and screw in the screw to decrease the maximum speed or turn it to increase. Tighten the nut after adjustment. The maximum RPM setting is necessary to protect the trimmer motor from overheating and to be able to use the start key lock to reduce right hand fatigue.

In the future, it may be necessary to readjust the trimmer carburetor. For example, if the engine starts to rev poorly when running at full load, loosen the screw another quarter turn. If starting is difficult, increase idle speed. Both weather conditions and the quality of the fuel mixture can affect the operation of lawn mowers. Vibration can cause the adjusting screws themselves to turn..

Idle speed adjustment

We start adjusting low speed. The screw limits the return movement of the throttle lever – by turning it, we increase the idle speed, unscrewing it, we decrease it. Adjust so that the engine runs confidently at low revs and even slightly accelerated (for better starting), but so that the line reel or knife does not rotate, and there is a sufficient reserve of revolutions before they start spinning. If the engine starts poorly, increase the idle speed even more..

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lawn mower or trimmer

A trimmer is a broader concept than a lawn mower (lawn mower), as it can also be electric. A petrol trimmer and a lawn mower are one and the same.

Some authors claim that the trimmer is a weaker tool than a more powerful lawn mower, which can be used for mowing shrubs. Personally, I have a tool with a maximum power of 1.7 kW and capable, as stated in the instructions, to mow small shrubs up to 10 mm thick. The user’s manual is called “Petrol trimmer …”.

Fuel supply adjustment

Start slowly tightening the fuel mixture adjustment screw until the engine starts to stall or stalls if you do not have time to catch the moment. After that, unscrew the screw a quarter of a turn if the engine did not stall, or half a turn if it stalled. Start the stalled engine. Check by opening the throttle as the engine picks up speed. Continue to unscrew the screw a quarter of a turn until the engine starts to accelerate steadily during gas blowing. This will be the moment of the most economical stable engine operation. For the PRORAB-8406 petrol trimmer, the adjusting screws are turned clockwise, unscrewed – counterclockwise, for some other brands the lawn mower can be the other way around.

Adjusting the carburetor lawn mowers, trimmer

Increased fuel consumption and the rapid formation of carbon deposits on the spark plug when using a properly prepared fuel mixture indicate the need to adjust the carburetor. Here’s how to tune trims with carburetors with one fuel adjusting screw..

Carburetor adjustment

Flush the air filter before adjusting the carburetor. It is recommended to rinse it after every 10 hours of operation. After that, you can start adjusting. The photo shows the PRORAB-8406 petrol trimmer carburetor as an example. The numbers indicate the adjusting screws that we will use.

PRORAB-8406 petrol trimmer carburetor adjusting screws

The purpose of the adjusting screws:

  • Fuel mixture adjustment screw.
  • Idle adjustment screw.
  • Maximum speed limiting screw.

Start a lawn mower and wait for it to warm up.

Spring may interfere

My first attempt to adjust the carburetor of the lawn mowers did not work, as the spring of the screw for adjusting the fuel mixture interfered with. The factory spring turned out to be too thick in the compressed state and did not make it possible to reduce the fuel supply to the required level. I had to pick up another spring and continue adjusting after replacing it.

Fuel mixture adjusting screw with spring

In the photo above the factory spring, below the adjusting screw with the matched spring. I am writing about this because I’m not sure if this is an isolated case, and someone else may face the same situation.

The principle of operation of the carburetor lawn mowers

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

Fuel is sucked into the carburetor system by a pump (its membrane). Then it passes through the choke in the carburetor. The fluid then flows through the pump inlet and outlet valves. Filtered by the grid. Moves through the needle valve into the diaphragm chamber.

Step-by-step operation of the device:

  • Air supply to a tube with an air baffle (damper). 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 the nozzle tube with a constriction. A float chamber adjusts the temporary volume of gasoline. In the float chamber, the pressure level is neutral, and in the tube with a constriction it is already low. Due to the differential pressure, the fuel penetrates through the nozzle.
  • The acceleration of the air flow facilitates 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 about creating an optimal fuel mixture through the correct air supply..

Do-it-yourself lawn mowers carburetor adjustment

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

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

Lawn mowers carburetor device

The basis of the carburetor for lawn mowers is an aluminum body. It contains a diffuser (hole with inner contours). Air is blown through this hole. The flow rate of oxygen (air) depends on the cross-section (orifice) of the diffuser.

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

Outside the carburetor is installed:

  • fuel pump;
  • jet system;
  • a system for adjusting the mixture of fuel and air;

The main problems and malfunctions of the carburetor.

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

  • Blockage.
  • Breaking.

In order to find out the cause of the breakdown, the fuel filter cap is unscrewed to remove the strainer. If dirt just accumulates on it, then flushing in gasoline or blowing 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 repair, they practice checking this element).

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

The throttle body, the places where the carburetor parts are bundled, the inlet or outlet pipe – all of these parts are susceptible to depressurization. You can check for sure in a primitive way – smear the problem area with soapy foam.

How to adjust the carburetor on a lawn mower

Before adjusting, you must thoroughly clean the filters according to the maintenance instructions in the instructions..

Further adjustment of the carburetor of the lawn mowers with their own hands is carried out with the adjusting screws. There are three of them:

  • right;
  • left;
  • lower.

Right (L) – adjusting the fuel mixture for low rpm.

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

To adjust, turn the screw a quarter turn counterclockwise.

Lower (T) – 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 overestimated speed of a hot engine;
  • a large reserve of turns for the trimmer head;
  • stable operation of the engine when changing position (sharp lifting or lowering of the knife).

Left (H) – mixture adjustment at high rpm. (The screw is adjusted last).

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

The carburetor setting for lawn mowers with the last screw is done as follows:

  • Open the throttle to full, at the same time give full throttle. Turn the screw clockwise until the speed drops (in this case, orientate 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, even operation.
  • For a more visual use 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 only by the speed and stability of the engine.

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