Setting The Chainsaw Carburetor. Do It Yourself.

To self-adjust the carburetor, you need to familiarize yourself with its device and remember the order of work that is carried out to adjust the parts responsible for the proper functioning of the components of the equipment and the parts nearby.
You need to carefully handle the items to configure the system, as well as determine the compliance of the set parameters with the maximum allowable values.
The carburetor is used to mix the combustible mixture with air while respecting the predetermined proportions. If correct doses are not observed, the engine is in good condition. When a large amount of air enters during the mixing of the components, and there is not enough fuel, this mixture is considered “poor”.
No oversaturation should be allowed, since, with a large amount of fuel compared to air, there may also be a malfunction or engine wear. Adjusting the carburetor is needed not only before the initial use but also when any deviations in its operation are detected. Before working with a chainsaw, do not forget to run it.
The design of the carburetor contains a standard set of elements, but may vary slightly depending on the manufacturer.


  1. The foundation. This is a special tube that is visually similar to the aerodynamic design. Through it passes the air. In the transverse direction in the middle of the pipe is a flap. Its position can be changed. The more it is pushed into the passage, the less air enters the engine.
  2. Diffuser. This is the gut part of the tube. With its help, the air supply rate increases precisely in the segment from which the fuel comes out.
  3. Channels for fuel supply. The fuel mixture is contained in the float chamber, then passes into the jet, from which flows into the sprayer.
  4. Float chamber. It is a separate structural element, reminiscent of the shape of the tank. Designed to continuously maintain the optimum level of fuel fluid before entering the channel, where air enters.

Every carburetor owner must have the necessary tools to make adjustments to this system. There are three adjustment screws, which are located on the device.

They have their own labeling:

  • L. screw for the correction of low speed.
  • H. the screw for adjustment of high turns.
  • T. regulates idling, in most cases is used for experiments.

Before adjusting the carburetor, you need to prepare the device:

  1. The engine warms up, that is, it starts about 10 minutes before the repair, and turns off at the start of work (see how to start a chainsaw).
  2. The air filter is checked and washed.
  3. Stops the chain by turning the screw T until it stops (see the oil for the chain).

To perform a safe repair, you need to prepare a flat surface where you can carefully position the device, and unscrew the chain in the opposite direction. Need a tachometer. It is determined by the presence of violations in the work of the carburetor. With screw turns, the sound should be perfect and smooth. If you notice screaming notes, then the mixture is oversaturated.
Adjusting the carburetor is divided into two main stages. The first is called basic. It is produced with the engine on. The second performs when the engine is warm.
To carry out the carburetor setting procedure successfully, you need to read the operating instructions in advance, specific model, to identify additional features of the device settings.
The adjusting screws of the highest and lowest revolutions should be held clockwise until the moment of meeting the highest resistance. When the screws reach the stop, you need to translate them in the opposite direction and leave with the passage of 1.5 turns.
The engine turns on at medium speed and so warms up about 10 minutes. The screw, which is responsible for adjusting idling, should move clockwise. It is released only when the engine enters the stable operation mode. It is necessary to check that the chain does not move during this process.
In idle mode, the engine may stall (the reason. here). In this case, you must immediately bring the adjustment screw clockwise until it stops. Sometimes the chain begins to move. In this case, turn the adjusting screw in the opposite direction.
Need to do a little research. The acceleration of the device is initiated. You should evaluate the health of the engine at the time of the maximum speed. When the engine is functioning correctly, it means when you press the accelerator, the speed quickly increases to 15,000 rpm.
If this does not happen or the speed increase is too slow, you need to use a screw marked with the letter L. It rotates counterclockwise. It is necessary to observe moderate movements since the turn cant be more than 1/8 of the full circle.
To limit this figure, you need to use a screw marked H. To increase the number of revolutions, turn it clockwise, and to reduce them in the opposite direction. The maximum frequency should not exceed 15000 rpm.
If you make this figure more, the engine of the device will work for wear, which will lead to problems in the ignition system. When rotating this screw, it is necessary to take into account the processes of ignition of the device. If there are the slightest failures, then the maximum value of turns needs to be reduced.
Before this procedure, you must perform a full adjustment of the components of the carburetor when working at maximum speed. Next, you should check the operation of the device in idle mode. When the correct parameters are achieved when adjusting,

You can see the exact matching design carburetor such criteria:

  1. When even a small press on the accelerator is carried out, the engine is accelerating at an accelerated pace. With a gradual deepening of pressure, you can see that the engine speed increases proportionally, reaching the maximum allowable values.
  2. When the engine is running, you can compare its sound with a four-stroke device.

If violations are noted in the above parameters or the device was not fully adjusted, you need to perform the main configuration step again. Sometimes actions are performed incorrectly. In this case, the device may fail due to the loss of the correct node settings. In this case, you will need to contact a specialist.
The device of different models of carburetors is almost the same, so when working with them, you can use the standard scheme. All items need to be removed carefully, and then lay out in the order given below, so that you can successfully place the items in place at the end of the repair work.

  1. The top cover is removed. To do this, unscrew the three bolts holding it in a circle.
  2. Foam rubber is also removed, as it is the top part of the air-conducting filter.
  3. The fuel hose is removed.
  4. The drive is displayed immediately on him.
  5. The tip of the cable is disconnected.
  6. Gasoline hose can be completely removed, if you systematically pull it from the fitting.

To finally prepare the carburetor for a major overhaul or replacement of the smallest parts, you need to disconnect it carefully from the main system. Sometimes it requires further disassembly. Unscrew the components carefully and fold the fasteners into groups, as these small parts are easily lost.
To properly configure the Chinese carburetor chainsaw, you must first remember the factory settings of the device, then turn on the engine. Subsequently, you will have to leave it to work for several hours to accurately set your parameters. Sometimes the work is done once after a ten-minute engine operation, but many Chinese-made models require special handling.

Adjustment order:

  1. Events start at idle. With the help of the adjusting screws, you need to achieve a steady set of engine speed, so you should first let it run at low speed. Deviation from the norm is the movement of the chain on the bus. In this case, you need to adjust the optimum position with the extreme screws so that the chain remains stationary.
  2. Transition to medium speed is underway.. Sometimes the engine smokes. This defect can be eliminated by tightening the screw to feed the leaner fuel mixture.

In this case, the smoke will disappear, but the engine speed will increase. It is necessary to adjust the settings to reach that level, when, when you press the throttle, the engine smoothly grows, no jerks or interruptions are heard.

  • Device engine check is performed.. The chainsaw is transferred to the minimum speed, and then there is a rapid push on the lever. With a maximum press, it is kept for 3 seconds. If there is a disturbance in the engine, you need to gradually loosen the screw until the optimum position is reached.
  • Chainsaw should work a few hours in real conditions. You need to engage in sawing wood, and then perform an inspection of all the elements involved in this event. If there are deviations, they need to be corrected, using adjusting devices. When all defects are eliminated and the optimum settings for the supply of properly concentrated fuel are established, the device setup process can be considered complete.

Before buying, we recommend that you familiarize yourself with the rating of chainsaws in terms of reliability and quality.
Look at the video:
For a chainsaw to work correctly, you need to carefully carry out work on adjusting the carburetor in exact accordance with their order. If there are any violations in the operation of the device, it is necessary to disassemble it completely. In most cases, it is required to replace any parts that have become unusable.
With constant verification of the quality of carburetor settings and the implementation of timely actions to improve its performance, there are no problems with the chainsaw.