How To Set Up A Chainsaw Carburetor? Recommendations.

Chainsaw carburetor is one of the main components of this tool. It is responsible for fuel supply. The efficiency and power of the equipment depend on how well this unit operates. The timely adjustment also ensures cost-effectiveness.
Before setting up the carburetor on a chainsaw, you should find out that adjustment of this part of the device is quite rare. As a rule, the factory setting is sufficient for normal operation. However, if a more precise adjustment is required, you can use special screws. Before starting such work, it is necessary to understand the subtleties and nuances of the process.

When carburetor adjustment is required.

If the adjusting screws were loosened, then the carburetor should be adjusted.

Other signs may also indicate the need for these manipulations, among them:

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

Additional signs.

If piston wear has occurred, then the engine will also need to be repaired, but the carburetor adjustment will act as a temporary measure, and the unit will become more stable. If the described node was clogged, which led to interruptions in the operation of the motor, then it will also be necessary to carry out washing.
Whereas when a situation arises when the engine stalls or does not start, it can be concluded that the working mixture was depleted. Incomplete combustion of the fuel mixture also indicates abundant exhaust. This conclusion can be reached if the tool began to spend fuel in an excessively large amount.

Preliminary manipulations.

To get to the carburetor, bolts are unscrewed on the tool cover. The housing must be opened, and the foam rubber, as well as parts of the air filter, must be removed. Only now, you can begin to adjust. Before setting the carburetor on the chainsaw, you should know that the main task of these works is the change in the quantity and quality of the air-fuel mixture, which is injected into the combustion chamber of the engine.

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During work, you must follow certain rules, including:

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

The first requirement is due to the need to avoid injury. If you have wondered about how to adjust the carburetor on a chainsaw, then you should know that you need to carry out these works using three screws. The first of them controls the nozzle and is denoted by the letter “H”. It is necessary to adjust the maximum speed.
The second screw can be found by the letter “L”. This node is necessary to control the idling nozzle at low revolutions of the shaft. Quite often, novice masters wonder about how to set up a carburetor on a partner chain saw. In it, the third screw is denoted by the letter “T”. It is needed to adjust the idle mode. The adjustment process is divided into stages: the first is conducted when the engine is off, while the second is on a warm engine.

Basic adjustment phase.

First, you need to use the revs. They are wrapped in a clockwise direction. Then turn back a half turn.

Final stage.

Before adjusting the carburetor on the Husqvarna chainsaw, you need to find the third screw, which is indicated by the letter “T”. Then the engine warms up for 10 minutes at medium speed. The third screw must be turned counterclockwise, waiting for the motor to start working steadily. The chain must be fixed.
If the motor stalls at idle, then the screw should be turned clockwise. When the target moves, the screw is unscrewed. If you are faced with the question of how to set up a carburetor on a chainsaw, in the next step, you should check how well the engine works at maximum revolutions during acceleration. It should be assumed that the engine functions correctly during acceleration, if, when you press the accelerator, the speed increases to a maximum value in the range from 2800 to 15000. The screw with the designation “L” must be turned to the left for the eighth part of the revolution.

Adjustment of the maximum number of revolutions.

Before adjusting the carburetor on the Partner 350 chainsaw, you must find the “H” screw. It is necessary to adjust the maximum speed. It should be rotated clockwise, whereas if it is necessary to reduce the number, the movement of the screw should be directed in the opposite direction.
You should set the maximum frequency in the range from 11,500 to 15,000 revolutions per minute. If this value is exceeded, the motor will work for wear, which will certainly lead to a violation during ignition. When turning the screw under the letter “H”, it is necessary to take into account how the ignition takes place. If failures occur, the rotation should be stopped by turning the screw counterclockwise.

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Idle check.

You need to know how to set up a carburetor on a Chinese chainsaw. In this case, it is also carried out a repeated check at idle. As soon as the adjustment in acceleration mode has been completed, the tool must be idled. If you did everything correctly, the chain would remain motionless, and the motor will gain momentum in a short time when you press the accelerator.
Should also listen to the engine. The sound should be like a four-stroke unit. If you are thinking about how to adjust the carburetor on a chainsaw properly, then you should take care that the above conditions are met. If this is not the case, the adjustment must be repeated, and the basic stage is omitted. You should not take up work if you do not have enough experience, because in this case, a node misalignment may occur. When self-tuning is not possible, stable work can be achieved by turning to professionals.

The nuances of adjusting the chainsaw “Stihl MS 250” carburetor.

You may have a question about how to set up a carburetor on a Stihl chainsaw. First, you need to decide when the need arises. The work described may be required if the spark plug electrodes change color. When it turns black, it indicates over-enrichment, whereas, with brick-gray, you can be calm, as this is the norm. When the master notices white bloom, he can be sure that the mixture is depleted.
The upper screw plays the central screw, it is located closer to the muffler in the described model. If you follow the factory settings that you can find on the tool cover, then this screw must be unscrewed by one turn and then corrected. When unscrewing the mixture will be enriched, whereas if the screw is screwed, the mixture will be lean, while a smaller amount of gasoline will get into the air-fuel mix.

The recommendations of the specialist to work with the carburetor chainsaws “Friendship”.

Before you adjust the carburetor chainsaw “Friendship”, you must carry out maintenance tools. 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. As soon as the screws “H” and “L” are turned up to the stop, they need to be turned out one turn. It should be done when the chainsaw is muffled.
Then the tool warms up, gets full throttle, and the first of these screws rotates in such a way as to reach 14,000 revolutions per minute. Maximum turns should be held for 10 seconds or less.
The method of turning the last screw should be to ensure that the chain began to move. Then the bolt turns back a quarter-turn counterclockwise. If after that the idle speed was not so stable, and the tool accelerates slowly, the screw under the designation “L” must be turned counterclockwise, only then the chainsaw will gain momentum.
It is important to remember that the adjustment will not give results if the air is sucked into the engine from the side.

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It can happen through:

  • accelerator pump;
  • carburetor;
  • gasket under the carburetor;
  • crankshaft oil seals.

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


To carry out the work, you will need not only a flat surface but also a tachometer, by which you will be able to identify violations in the operation of the adjustable node. When turning the screws, the sound should be even, if you notice a screeching note, this indicates that the mixture is over-saturated.
If you do not have enough experience, then before starting work, you should familiarize yourself with the principle of operation of the carburetor, which functions in the same way as an internal combustion engine. It triggers a small explosion that occurs in the ignition cylinder of the mixture. The pressure from this process pushes the piston, which rotates the crankshaft. The movement develops into the rotation, which moves the chain through an asterisk. With optimal performance, the engine consumes up to 10 mg of fuel in each cycle while the mixture for the engine is prepared in the carburetor.