How to adjust the carburetor on a chainsaw caliber

Table of Contents:

Avinir ›Blog› Chainsaw Caliber BP-1500 / 16U

(upd 13.08.2018: Alas, for a long time this model of the chainsaw has not been on the official website of the brand, and is not available on Ali)

Peace to all!
With the onset of cold weather, the problem of heating the garage arose. It seems to have solved the issue with heating the garage. I cooked a stove, but at the same time the problem of warming the garage surfaced. I decided in a half measure. I repaired the cracks in the gate by gluing foam rubber on the ends of the gate along their perimeter, and covered it with snow from below. Then the question arose of where to get firewood for a wood-burning stove. Directly a quest of some kind, when it is not mediocre to repair the delica.

Considering the proximity of the forest, in which a strong atypical hurricane for our area took place several years ago, knocking down a bunch of trees, the “rapidly” developing ASEZ “Mountain Air”, and the state program for the demolition of dilapidated housing, the issue can be said to be resolved. go and take it))) But there is nothing to take (((I need a saw.

So, my first chainsaw. Mighty domestic Chinese chainsaw “Caliber BP-1500 / 16U” for 3590 rubles. 3590 rubles, Karl! (purchase date 11/30/2017, after NG 100 rubles cheaper))) True, I had to modify it a little, about which later.

This saw, externally and internally, is very similar to a number of other Chinese chainsaws, for example Foresta xxx, WL4500, GOODLUCK GL4500M, Carver Promo PSG 45-15, Bison, etc. I wonder which model of the saw was originally copied from?

For example, here is an interesting article on how to distinguish a real Chinese saw GOODLUCK GL4500 from a Chinese fake))))

Complete set: cover / tire casing, file, container for mixing fuel, screwdriver, combination wrench, hex key 2 pcs., User manual. Round file, 4mm diameter.

A fairly detailed review of this chainsaw and many high-quality photos of it are in the review on the website

What amazes me most is that almost everything is made in China: both Makita and the vaunted iPhones. Why pay extra for a brand label? So, of course, I have proletarian solidarity with Rothschild, who said: I am not rich enough to buy cheap things. In short, time will tell.

When I poured motor oil into the chain saw, I checked it. it seemed like something was splashing. I made a test cut of the lumps. I checked the oil on the chain again, but the oil doesn’t go. Well, I think, in the cold, the oil thickened and the oil pump drive gear was licked or even worse. The service center said they will send the saw to Khabarovsk, the time frame is 45 days. In a paid workshop, 1000 rubles were asked for repairs with replacing the gear and / or pump. In short, I decided to disassemble it myself. It turned out that there was simply no hole in the oil filter, which is at the end of the hose in the oil tank (oh, of course there was a hole)! Corrected. It all worked. But now there is no guarantee. In vain I dismantled it to the oil pump, it was necessary to start with the filter. Who knew.

Overall, I am very pleased with the purchase.

Update as of 12/05/2017:

On the issue of running a chainsaw on the Internet, there are polar opinions. At first, I let it idle for about 30 minutes with periodic re-gasings. Then, as a gentle running-in, he slowly sawed his first cubic meters of firewood from dry boards and beams left over from a dilapidated house, which was more than 50 years old, and also sawed a couple of nails. Burned one and a half tanks of fuel.

Update as of 12/21/2017 (or the end of the running-in?):
When I started to harvest firewood there for the second time, i.e. already on the third tank and cubic meter, the saw somehow changed in behavior. The saw began to start badly, and then at the end it began to stall when the gas was pressed. After searching the Internet, I realized that the problem is known. it requires adjusting the carburetor settings. over, after “running in” (the term itself in relation to chainsaws is very controversial), many sources recommend contacting the service to adjust the settings of the saw carburetor.

By the way, the carburetor in my standalone chainsaw with the inscription “Wanbao” (with primer). A search in the internet for this name gives out links to the “Walbro” carburetor, which is apparently the “original”. But in nature there are also variants with the inscription “Wangbo”.

Perhaps the problem with the poor starting of the saw was that I added a little more oil to the gasoline in the manufacturer’s recommended proportion for the “break-in” mode, but this seems unlikely to me. Nevertheless, according to the videos on the Internet (I attach one of them below) I independently adjusted the carburetor:
1) tightened the adjusting screws “L” and “H” clockwise;
2) unscrew the adjusting screws “L” and “H” by 1.5 turns (coarse adjustment);
3) started the saw, warmed up a little at idle with periodic re-gasings;
4) rotating the screw “L” achieved the maximum idle speed (lean mixture)
5) unscrewed the screw “L” by 1/4 turn (enriched the mixture, such as otherwise prolonged work on the lean mixture is fraught with overheating)
6) tightened the “L” screw a little more so that when the gas is pressed sharply, the saw does not stall (adjusted the throttle response);
7) (if necessary, adjust the idle speed with the screw “T” if the chain starts spinning);
8) I did not adjust the maximum revolutions by ear, but during the trial sawing of the log I slightly adjusted the screw “H” when the saw clearly did not have enough power (fuel).
(I do not pretend to be the ultimate truth, I do it because I understood the processes taking place based on the studied (often contradictory) material from the Internet).

Later I bought a digital tachometer RLHM035R (review / instruction) and measured what I adjusted:
– XX. 3900 rpm (but the chain was standing, although at such speeds it should spin – I believed the video below))). lowered the screw “T” to 3000 (later observations showed that with a cold start, the XX 3300, as it warms up, falls to 2700, and then 2700-3100 jump, even later I found out that now after a long work, i.e. at maximum speed under load, if the gas is released revolutions fall below the lowest and the saw stalls. raised XX to about 3100). And even later I read the Instruction, which says that XX is about 4000.
– Maximum. 10,900 no load (according to the passport maximum 11,000). so left.

Further reference information:

Somewhere in the middle of summer, a neighbor in the garage asked for a saw. Returned with new Oregon 91VXL057 chain. Said that the chain (native) ran into a nail and broke (((
(there is also an Origon 91P056X chain in stock)

Recently I had a chance to saw a log thrown out by the sea with a diameter not much smaller than the length of the saw bar of a chainsaw. When I saw the middle of the log I noticed that the power seemed to be lacking, the saw was pushed into the return line.

Surely, with the same length of the saw bar, but with greater power, this effect would not have manifested itself. Perhaps, including for this reason, this model was removed from sales, but this is not certain))

A friend bought a chainsaw Caliber BP-1800/16 PROMO. In appearance, she is very different from non-PROMO, it seemed to me more like a “gypsy”.
In addition, there is no heat insulator between the cylinder and the muffler, the ignition switch is a toggle switch. The plastic of the air filter and starter is of other shapes, more rounded. probably not compatible with the “classic” Caliber (but this is not certain). And also there is no partition between the muffler and the cylinder, which improves the airflow of the latter. The color of the plastic is different (this is nitpicking)))
Turnover of XX was 4500, lowered to 3000.

And more about “Promo”. I wrote a letter to the sales department of “Caliber” and asked, what is the difference between chainsaws of the “Promo” series. To which they answered me directly and honestly: cheaper plastic and components.

By the way, the model range included saws with a shorter 14 “saw bar (Caliber bp-1500 / 14u), as well as a lower power with a CPG volume of 38 cm3 (Caliber bp-1300 / 16u, Caliber bp-1400 / 16u).

How to adjust the carburetor on a Chinese instrument

Let’s figure out how to properly adjust the carburetor on a Chinese chainsaw of different brands. The setup principle is similar to that described in the material above. First you need to inspect the tool, and identify the presence of adjusting screws. Usually the T screw is on the top and the L and H screws are below. Access to these screws does not always require you to remove the protective cover or shroud.

If the Chinese chainsaw has a different number of screws, then based on their number, you need to make the appropriate adjustment. The device and principle of operation of all chainsaws of different brands and manufacturers is approximately the same, therefore, there will be no problems with adjustment.

It is always easy to do any new job, if there are instructions, so do not be afraid to tackle the setup. Even if you do something wrong, then by contacting a specialist, he will definitely point out your mistakes. If you have any difficulties with adjusting the chainsaw carburetor, then describe them in the comments. Experts, masters and just amateurs, together with the founder of the portal, will help you understand this issue.

To self-adjust the carburetor, you need to familiarize yourself with its device and remember the operating procedure that is performed to adjust the parts responsible for the correct functioning of the component parts of the device and the parts adjacent to it.

It is necessary to carefully process objects for configuring the system, as well as to determine whether open parameters correspond to the maximum allowable values.

Chainsaw carburetor adjustment instructions

Setting up a chainsaw carburetor begins with a preparation procedure. The preparation is based on the following actions:

adjust, carburetor, chainsaw, caliber
  • Check the air and fuel filter for contamination, and if any, these elements need to be cleaned
  • Check the diaphragm for damage
  • Serviceability of the needle valve
  • No air leaks, which can occur due to leaky oil seals, gaskets and seals

After making sure that the carburetor is in good working order, you can adjust it yourself. It is possible to restore the mechanism to its factory settings, but it is not always necessary to do this. Instructions on how to adjust the carburetor on Stihl, Husqvarna, Makita, Dolmar, Champion, Sadko and others chainsaws are described below. Initially, we find out what each screw in the mechanism is intended for:

  • Screw H. main jet, which is responsible for setting the maximum number of revolutions of the tool
  • Screw L. XX jet, which is needed to set low idle speed
  • Screw LA or S or T. increasing and decreasing the amount of mixture supplied to the cylinder

Adjusting screws what do they mean

Each type of tool of the brands Stihl, Husqvarna, Makita, Dolmar, Partner is accompanied by an instruction, which contains a section that describes this process in detail. It will not hurt if you find the instructions before setting up, and read it before turning the screws.

READ  Chainsaw attachment for cutting logs onto boards

Preparing for setting up the chainsaw carburetor includes performing the following manipulations:

  • Installing a chainsaw with your own hands on a flat surface. It is also recommended to secure the tool so that it does not move when you push the screws with a screwdriver.
  • Steer the tire away from you
  • Provide a safe distance for others, since the carburetor of the chainsaw is adjusted with the engine running
  • It is not necessary to remove the carburetor from the unit to adjust it

Chainsaw mechanism tuning process:

This is not the end of the regulation process, but the tool can already be tested in action. For beginners and inexperienced sawers, it is recommended to complete the setup process at this point. For a more accurate adjustment of the carburetor of the chainsaw, you need to set the maximum speed. Let’s start setting up the H screw for experienced sawers:

  • Determine the enrichment of the mixture by the exhaust. To do this, we develop the revs to the maximum, and look at the nature of the exhaust. The presence of gray smoke and strong vibration of the instrument indicate excessive enrichment of the mixture.
  • The tachometer (if connected) will show a large number of revolutions. more than stated in the characteristics
  • To reduce the maximum speed, you need to move the screw H a few turns counterclockwise
  • The maximum speed is checked again, and the process is repeated if necessary.

You can make sure that the instrument is configured correctly by the following signs:

  • The chain does not move when idling
  • The engine works like a four-stroke engine
  • When you press the throttle stick, the engine responds quickly and revs up

To make the most accurate tuning, you will need to use a wired or wireless tachometer.

Tachometer for fine tuning

Husqvarna Saw Carburetor Adjustment.

For the break-in mode, so that the parts receive sufficient lubrication, the carburetor setting of the Husqvarna chainsaw is made so that the maximum speed is 600-700 rpm. below working. If it is not possible to set the operating maximum frequency by the tachometer, you should not change the presets with the H screw. It is forbidden to exceed the value of the maximum number of revolutions by the manufacturer. If, after completing the adjustment, the saw chain moves when the engine is idling, turn the screw T counterclockwise to bring it to a complete stop.

For accurate adjustment, the saw must be warmed up for at least 10 minutes, set on a flat surface. The tire should point away from the person making the tune. At the initial stage, the highest idle frequency should be found. To do this, screw L is smoothly turned first from left to right, then vice versa. When the maximum revolutions are found empirically, screw L should be unscrewed counterclockwise by a value from 1/8 to a quarter of a full revolution.


Idling is adjusted by the nozzle marked with the letter T. It must be turned from left to right until the chain starts to move. Then gently feed in the opposite direction until the rotation of the chain stops. Chainsaw carburetor adjustment is performed in the chainsaw should work. Screw H is considered to be installed correctly if the noise of the saw at full throttle without load remains small. If the exhaust is too smoky and the saw makes a lot of noise, the mixture is too rich. It is necessary to turn the H jet clockwise until the correct sound is set. How to properly tune the carburetor, you can watch the video below.

How to adjust the carburetor of chainsaw

The video shows a simple but effective way to adjust the carburetor using an inductive tachometer. Looks like

Chainsaw carburetor tuning. Or how not to pay repairmen!

Owning a chainsaw makes life much easier even for an amateur, and in some professions this tool is virtually indispensable. However, like any relatively complex device, a chainsaw requires periodic maintenance. Due to untimely or poor quality maintenance, as well as as a result of the impact of both planned and excessive loads, various kinds of malfunctions may appear. For professionals, interruptions or erratic saws reduce efficiency or can lead to a ruined working day. One of the fairly common malfunctions is the incorrect setting of the chainsaw carburetor, which gets lost due to unsuccessful attempts to adjust or displace the adjusting screws for other reasons.

adjust, carburetor, chainsaw, caliber

About the carburetor device

The carburetor is used to mix the combustible mixture with air, observing the predetermined proportions. If precise dosages are not followed, engine performance is compromised. When a large amount of air is supplied during the mixing of the components, and there is not enough fuel, this mixture is considered “lean”.

Supersaturation should not be tolerated, as with a large amount of fuel compared to air, engine failure or wear is also possible. Carburetor adjustment is necessary not only before initial use, but also if any abnormalities in its operation are detected. Before you start working with your chainsaw, do not forget to check it.

HOW TO ADJUST the Carburetor on the Homelite Timberman 45 Chainsaw

Carburetor components

The carburetor design contains a standard set of elements, but may vary slightly depending on the manufacturer. Components:

  • The foundation. It is a special tube that visually resembles an aerodynamic design. Air passes through it. There is a damper in the transverse direction in the middle of the pipe. Its position can be changed. The more it is pushed into the passage, the less air is supplied to the engine.
  • diffuser. This is the longest part of the tube. It increases the air flow rate exactly in the segment from which the fuel comes out.
  • channels. The fuel mixture is contained in the float chamber, then flows into the jet, from which it flows into the sprayer.
  • Float chamber. It is a separate structural element that resembles the shape of a tank. It is designed to constantly maintain an optimal level of fuel fluid in front of the entrance to the channel from where the air enters.

Not sure which chainsaw to choose? Read our article.

Looking for a cheaper model, but reliable and time-tested? Russian chainsaws.

Or research foreign chainsaw manufacturers like Calm.

Chainsaw Gauge Carburetor Setting

A chainsaw is a complex unit, the operation of which is based on a two-stroke type internal combustion engine. The internal combustion engine requires the use of a carburetor. In this mechanism, fuel is mixed with air, and this mixture is fed into the engine cylinder for combustion. The operation of the internal combustion engine largely depends on the carburetor, which needs periodic adjustment. Chainsaw carburetor adjustment can be done by hand, but for this you need to know the instructions, which are described below.

Partner Model: Setting Up in Detail

One of the popular brands of chainsaws is Partner. Using her example, we will consider the process of adjusting the carburetor. To work, you need a tachometer (a measuring device for determining the speed of rotation of the mechanism).

You can clearly see how to adjust the carburetor on a chainsaw in the video below. The manufacturer uses three types of screws in the design:

  • H (allows you to adjust the low speed);
  • L (to regulate high revs);
  • T (idle speed correction).

The last screw is visible to the user, and only he has access to it, if the work is carried out at home. The Partner chainsaw (as well as other models. Stihl, Ural, Druzhba) is adjusted in stages and only on a hot engine.

Using the adjusting screw (as shown in the photo), with a slight movement from left to right, stop the chain until it is completely braked. You need to install the chainsaw on a solid, flat surface, the rotating element is turned in the opposite direction from you.

Important: if the reason for the breakdown of the carburetor is the use of low-quality fuel, the exit from the standing (contamination) of the filter, in parallel it is necessary to flush it. The wear of the piston elements is a problem that cannot be solved with minimal effort; a major overhaul is needed. In such cases, it is possible to adjust the carburetor on a Partner chainsaw (Ural, Druzhba) only with the involvement of a professional master who has special equipment and tools.

Carburetor device and breakage

One of the main components of the chainsaw mechanism is the carburetor. Its principle of operation is similar to that of an internal combustion engine. A small explosion in the cylinder after combustion of the mixture activates the piston, which rotates the crankshaft. The motor operates in a cyclic type, which reduces the risk of its failure.

You can find out that you need to adjust the carburetor of a chainsaw by the following signs:

  • the motor often stalls or does not start at all (often associated with the use of a poor-quality mixture);
  • looseness of the fastening of the screws, malfunction of the protective cap (the reason lies in the intervention of the owner in the design);
  • high fuel consumption and increased emissions (oversaturated low-octane mixture, often used).

Chainsaw speed control

The sequence of screws for fine tuning: L. H. T (step by step instructions shown in the video). The first is responsible for the number of revolutions, it is turned from left to right or in the opposite direction to the maximum mark. It is worth doing such actions gently and without pressure.

The speed limit, which can be adjusted quickly, is determined by ear by the master with sufficient experience or by using a tachometer. The regulator H fixes the limit point (turns by about a quarter of a turn of the screw). If it is determined incorrectly, you can damage the engine, and the chainsaw can no longer be used without major repairs. Idling must be adjusted with screw T. It is smoothly turned counterclockwise until the chain stops. Thus, you can adjust the speed on any model of chainsaw. All actions are carried out on a warm engine.

How to adjust a chainsaw: carburetor, rpm, ignition

A chainsaw is an important economic element that allows you to perform a lot of household work in a short time, which the owner cannot cope with on his own. This complex mechanism with many parts will work smoothly only with timely and high-quality service. You can quickly adjust the chainsaw yourself, guided by the basic rules applicable to this category of equipment and the user’s manual.

How to adjust the ignition

Malfunctions in the ignition system render the chainsaw engine inoperative. The owner simply cannot start it at the right time, or this process becomes lengthy and unproductive.

Correctly adjusting the ignition on the chainsaw is possible only if the exact cause of the breakdown is determined. First you need to remove the candle using a special key, having previously disconnected the high-voltage wire from its head. It may be wet. this is a signal of an excess of fuel or that you have not been able to properly adjust the carburetor. The candle is dried, then the starter is started. this will remove the remaining fuel. This way you can tune your Husqvarna chainsaw and other models to a high level of performance.

If black carbon is present, clean the electrodes and spark plugs with a fine needle. You can adjust the ignition by checking for a spark. With the skirt of the candles, they touch the cylinder and set the starter in motion. If you cannot adjust the ignition using the above methods, you can try to replace the element with a new one.

How to determine if the setting is correct

If you are not sure that the owner was able to properly adjust the Partner chainsaw (or another model) on his own, pay attention to the carburetor operation. It must have the following characteristics:

  • idling does not move the chain,
  • engine starts quickly,
  • the sound is clear, without noise and crackling.

You can adjust the ignition and speed of the device at any time, as soon as there is a suspicion of a malfunction.

one per entry “How to adjust the chainsaw: carburetor, rpm, ignition”

Husqvarna 137. I changed a new cylinder with a piston, the carburetor does not cut it, and there is no idle. Screws L and H twisted stalls, there is no low speed. How to be?

How to adjust the carburetor on a chainsaw: don’t miss important details

So that an attempt to adjust the carburetor on a chainsaw is not meaningless, you must:

  • study the instructions from the manufacturer;
  • get a tachometer if you are not a professional carburetor;
  • make sure the filter is clean;
  • install the unit on a level place, direct the chain away from you.
READ  How to Make a Snowmobile Out of a Chainsaw

The principle of operation of carburetors is the same for different models of chainsaws, but the number of screws used in the settings may differ (1 or 3). The second option is more common, but it happens that the manufacturer leaves access to only one.

Before adjusting the carburetor on a chainsaw, you should familiarize yourself with the decoding of the designations indicated on the screws:

  • H. high speed setting.
  • L. low speed adjustment.
  • T (LA or S). idle speed correction.

The basic (factory) setting is carried out when the engine is off, and the final debugging must be done in working condition.

How to adjust the carburetor on a chainsaw: DIY tips

Ordinary users do not often ask themselves the question: “How to adjust the carburetor on a chainsaw?” Few people are ready to try to solve such a problem on their own, but daredevils are still there. The need to adjust the carburetor may be indicated by:

  • excessive vibration of the instrument;
  • engine stop immediately after start or complete absence of start;
  • abundant exhaust of gases;
  • increase in gasoline consumption.

How to adjust the carburetor on a chainsaw: you can start tuning

First you need to tighten the screw L, and then H along the thread until it stops, and then turn them in the opposite direction by 2 turns. Next, we proceed to debugging the idle speed (with the engine running). We adjust the screw L in different directions until we find the highest speed. After the adjustment, the chain should not rotate at idle speed. If this happens, the screw T (LA or S) must be turned counterclockwise until it comes to a complete stop. Next, we proceed to adjusting the maximum maximum speed. Acceleration is checked last. When you pull the throttle trigger, you should notice if the engine is quickly revving up to maximum speed. If yes. debugging is successful if not. the procedure must be repeated.

Adjustment tools

To tune the carburetor, you will need a Phillips or slotted screwdriver of different lengths or thicknesses, the size depending on the design of this unit and the features of the engine assembly. It should be noted that some manufacturers make carburetors designed to use special tools.

In particular, special types of screwdrivers may be required to tune Husqvarna carburettors and other imported tools. It is advisable to clarify this question even when buying a chainsaw, so that you can purchase the necessary additional equipment in advance.

In addition, you will need refined gasoline or acetone to flush and clean the device. They are used to clean the outer surfaces of the carburetor. All internal channels are flushed with kerosene, diesel fuel or white spirit. Before washing, the carburetor is disassembled, all rubber or plastic parts that may suffer from contact with aggressive chemical compounds are removed.

Open-end or spanner wrenches are used to disassemble the carburetor. The internal channels are flushed in specially designated trays, sometimes plastic syringes are used for this.

Design and principle of operation

A carburetor is a device in which fuel (gasoline) and air are mixed in predetermined proportions, followed by feeding the prepared mixture into the engine cylinder. Almost all models of chainsaws are equipped with carburetors of the same type, so the device and principle of operation are the same.

The main structural elements of the carburetor are:

  • body, which is cast from aluminum to reduce weight. Chainsaws constantly have to be moved from place to place, during operation they are held by hands, therefore, reducing the weight of the tool is the primary task of manufacturers;
  • diffuser with an air damper, which are located at the inlet;
  • nozzles, which are valves for metering fuel supply;
  • a sprayer that injects gasoline into the chamber (in the diagrams it is designated as the main jet);
  • fuel (float) chamber.

Figure 1. Diagram of a chainsaw carburetor

The principle of operation of the carburetor can be described as a cycle consisting of the following steps:

  • Air damper opens during engine start.
  • The piston stroke creates a vacuum in the air channel, as a result of which air enters the diffuser, the amount of which is regulated by the position of the air damper.
  • Gasoline flows from the gas tank to the float (fuel) chamber. The rate of its admission is regulated by jets.
  • In the diffuser, gasoline and air are mixed, resulting in the formation of a fuel-air mixture, which then enters the engine cylinder. The more the mixture enters the combustion chamber of the cylinder, the higher the power and speed on the engine shaft will be.

Important! It should not be assumed that the operation of the carburetor is cyclical, as it might seem from the description. All processes take place constantly and continuously.

How to properly adjust the carburetor on a chainsaw with your own hands?

A chainsaw is a useful, and sometimes just a necessary tool for the owner of a private house. It has a high degree of autonomy, can be used in the field, where there is no possibility of connecting to the power supply network. For some craftsmen, the chainsaw is one of the main devices that perform large amounts of work almost daily. Such loads knock down the factory settings that were set for all important engine components.

The operating mode most often changes at the carburetor, which has to be re-adjusted. Not having an idea of ​​the design and principle of operation of this element, it is impossible to properly adjust it. The question concerns many users who closely operate chainsaws, so it will be useful to consider it more carefully.

  • Design and principle of operation
  • When carburetor adjustment is necessary?
  • Adjustment tools
  • How to properly adjust the carburetor with your own hands?
  • How to set up a China-made saw?

How to properly adjust the carburetor with your own hands?

After rinsing and completely cleaning the carburetor, assemble it and start adjusting. First of all, you should understand the purpose of the adjusting screws. The instruction will help with this, but some general points should be considered right away. The most common designations for screws are:

  • H. adjusts the state of the main jet, i.e. adjusts the maximum speed of rotation of the motor shaft;
  • L. adjusts the idle jets (responsible for the minimum shaft rotation speed);
  • T. regulates the idling of the motor. It can also be designated by the letters LA or S, on some models of carburetors it is not at all.

Turning screws H and L clockwise depletes the fuel-air mixture, and counterclockwise enriches it (the amount of gasoline increases). When the screw T rotates, the idle speed of the shaft changes. it increases clockwise, and decreases in the opposite direction.

Figure 2. Carburetor adjustment mechanisms

Before proceeding with direct actions, you should find and carefully study the information on the position of the adjusting screws (the magnitude of the angles of rotation when adjusting). This information is available in the instructions for the chainsaw. Then you need to prepare the workplace. lay the saw on a flat horizontal plane, directing the chain in the opposite direction from you. Detach all covers, remove foam rubber and air filter. At this, the preparatory operations are considered completed, you can proceed to the main part of the work.

Carburetor setting procedure:

  • Smoothly tighten screws H and L clockwise until they stop. Be careful not to break the screws. this will cause a complete loss of the carburetor.
  • Unscrew both screws one and a half turn.
  • Run the engine for 10 minutes and warm it up. This is a necessary moment, since it will not be possible to correctly adjust the carburetor on a cold engine.
  • Turning the screws H and L, alternately adjust the rotation of the shaft at maximum and minimum revolutions.
  • By adjusting the position of the screw T (or it may have another designation), the idle speed of the chainsaw is adjusted. It is necessary to achieve smooth and stable engine operation. It is important to monitor whether the chain is idling or not. If it moves, turn the screw a little more counterclockwise.
adjust, carburetor, chainsaw, caliber

Important! It is better not to adjust the screw H for an inexperienced person. If it is not set correctly, a lean air-fuel mixture will be supplied to the combustion chamber of the cylinder at maximum speed. This will lead to accelerated wear of the piston group.

You can check the operation of the engine visually and by ear. A mixture that is too rich will cause thick smoke from the exhaust. When the lean mixture is being fed, a whistling sound is heard while the saw is running. Excessive economy mode is harmful. if the L screw is set to “lean” fuel, there will be problems with starting the engine. If the H screw is set to lean, the saw will noticeably lose power. You can determine the correct setting by the following criteria:

  • at idle speed, the engine does not stall, and the chain is stationary;
  • there is no excessive smoke from the exhaust pipe while the engine is running;
  • the engine demonstrates good throttle response (quickly picks up speed when you press the accelerator).

A detailed description of the setting is available in the instructions that come with the instrument in the delivery set. It should be carefully studied, as there may be some features or specific requirements established by the manufacturer and related only to this saw model. If all requirements are met exactly, the performance of the chainsaw will be restored to its original state.

When carburetor adjustment is necessary?

Initially, from the moment the tool was sold, all carburettors were adjusted and tuned at the factory. However, in the process of operation, the settings gradually go astray, and the operating mode changes in accordance with the operating conditions. Signs of a malfunctioning carburetor may include:

  • too high gasoline consumption, thick smoke comes from the exhaust pipe;
  • engine power is clearly not enough to perform normal tasks;
  • engine speed “float”;
  • after starting, the motor stalls either immediately or after a few seconds;
  • the engine cannot be started at all;
  • the chainsaw “shoots”, there are sharp claps in the engine of the tool.

Note! The reason for poor engine performance may be the worn out piston group, then adjusting the carburetor of the chainsaw does not give a full solution to the problem. Also, no setting will give the expected effect if the node is not cleaned of small particles of debris in parallel. The most problematic elements are jets and filters, both gasoline and air.

It should be noted that during the running-in of a new engine, the carburetor is adjusted to a reduced fuel supply in order to limit the engine power. After the end of the run-in, the fuel supply increases to the nominal value. These adjustments are made using the adjusting screws on the carburetor body (there are usually two or three).

How to set up a China-made saw?

The design of the carburetor on Chinese chainsaws is no different in principle. The order and principle of adjustment also do not differ and are performed in the same order. The only difficulty that may arise during the execution of work is determining the purpose of the adjusting screws. Typically the T screw is on the top and the H and L are on the bottom of the carburetor body. One more, additional screw may be present.

Figure 3. Location of adjusting mechanisms

How To Tune A Chainsaw | Adjusting The Carburetor

Usually, their purpose is determined empirically, slightly changing the position and monitoring the result. After the purpose of the elements is clearly defined, further customization is not difficult and is performed in the usual manner.

Chainsaw carburetor tuning is an important and necessary procedure that must be performed periodically to restore the normal operation of the tool. This process does not create fundamental complexity, but it requires the user to be careful, attentive and comply with safety rules. The chainsaw chain is usually not removed, since you will need to observe its position. Therefore, it is important to constantly remember about the possibility of launching it and exercise the necessary caution.

The adjustment should be done smoothly, with small changes in the position of the screws, so as not to cause too sharp changes in the shaft rotation mode. The result depends on the care and thoroughness of the user, and a properly tuned carburetor will extend the life of the tool.

How to properly adjust the chainsaw carburetor

During the operation of the tool, situations arise when it is necessary to adjust the carburetor of the chainsaw. Within the framework of the article, we will figure out when to configure, how to do it correctly and whether it is worth adjusting it yourself, or is it better to give it to a specialized service. The carburetor is an important unit, the service life of the saw depends on how correctly it works.

  • Situations in which adjustment is necessary
  • Tools
  • How the carburetor is adjusted?
  • Process description
  • Adjusting the carburetor of a Chinese chainsaw
  • Video
  • Summing up
READ  Replacing a Fuel Hose on a Chainsaw


To adjust, you will need the following tool: a tachometer, screwdrivers, in rare cases, special keys. We will analyze their purpose, the need for availability and cost.

Tool Appointment Recommended
Screwdriver set (slotted screwdriver) Most chainsaws require a simple flat-blade screwdriver to turn the adjusting bolts. 300. 700 rubles Required
Special adjusting key For example, to adjust the carburetor on Husqvarna chainsaws, a special key is required, it is available only in certified service centers authorized for repair by the manufacturer. This measure is aimed at reducing breakdowns due to incorrect settings by inexperienced users and those who are engaged in repairs without official permission to do so. Out of stock Chainsaw dependent

Setting up the chainsaw, if possible, should be carried out in official service centers that have a manufacturer’s certificate and an appropriate permit for repair work.

adjust, carburetor, chainsaw, caliber

How the carburetor is adjusted?

The algorithm for setting up the chainsaw is quite simple and consists of the following steps:

  • Warming up the engine to operating temperature (the adjustment must be carried out only on a warm engine, this will allow you to get a more accurate adjustment).
  • Adjusting the engine for smooth operation at low rpm.
  • Setting the carburetor for the correct supply of the fuel mixture at maximum speed.
  • Fine adjustment of the carburetor for idle operation.
  • Chainsaw check in all modes.

Almost all carburetor models have three adjusting screws.

  • The screw (T) is responsible for fine tuning in idle mode.
  • Screw (H) setting for maximum speed.
  • Screw (L) regulates the formation of a mixture at low rpm.

By tightening the screws (L) and (H), the fuel supply and the mixture becomes leaner, respectively, the speed increases.

Carburetor adjusting screws L. minimum rpm and H. maximum engine rpm.

Now let’s look at how the correct adjustment of the chainsaw carburetor goes in more detail.

Process description

  • If the carburetor of the chainsaw is not adjusted and it is not possible to start the chainsaw, then the adjustment starts by setting the screws (L) and (H) to the standard setting. This is 1/5 of a turn of the screws until completely tightened.
  • After that, you need to start the engine, let it run a little and warm up.
  • The next step is to set up the low speed mode. Optimum low engine performance can be achieved by adjusting the screw (L) and idle speed (T). To do this, first the screw (L) is tightened until the maximum engine speed is obtained, then it is released by 1/4, and the idle speed is normalized with the screw (T).
  • After adjusting the work on the “bottom”, the thrust and maximum engine speed are adjusted. To do this, slowly tighten the screw (H) and check the speed according to the readings of the electronic tachometer. It is unacceptable to allow exceeding the maximum engine speed declared by the manufacturer!

The location of the carburetor adjusting screws on the Husqvarna chainsaw.

An important step is to check the saw in all operating modes after adjustment, for this you need to let the chainsaw cool down, and then start it according to the cold tool start algorithm. If the saw starts up normally and idles smoothly, you need to check how it is sawing. If in the process of checking deficiencies in the power of the chainsaw are found, then it is necessary to repeat the adjustment of the screw (H) by unscrewing it and checking the thrust in operation.

Loss of thrust at maximum RPM recommended by the manufacturer is an indicator of CPG wear or poor fuel quality. Speaking of fuel, 90% of faults are due to fuel. Which one to use? 92 or 95? How much is stored? We answered all these questions in the article on which gasoline to pour into the chainsaw.

We recommend watching a video on how to clean and adjust the carburetor of a chainsaw, the author of which also talks about the detrimental effect of fuel on the components of the carburetor. This example shows how to rebuild your carburetor using an inexpensive repair kit.

Adjusting the carburetor of a Chinese chainsaw

Carburettors installed on Chinese-made saws are made similarly to European ones and have the same adjustment screws.

The carburetor of a Chinese chainsaw is adjusted according to the algorithm presented above, and differs in that during the initial setting of the screws (L) and (H) they must be turned out two turns. Further, the carburetors of the Chinese saw are adjusted in the same way as the European ones.

How to adjust the carburetor of a Chinese chainsaw in just 3 steps, read here (a very useful article). As an example, we recommend looking at the article about adjusting the carburetor on the Carver chainsaw.

Situations in which adjustment is necessary

New chainsaws are supplied by the manufacturer with adjusted carburetors. This is called standard adjustment. But for the normal passage of the running process, it is required to lower the maximum engine speed, adjust the carburetor. After running in, the chainsaw needs to be fine-tuned to achieve maximum engine efficiency.

Also, a signal for cleaning and adjustment is an increased fuel consumption, which negatively affects the operation of the exhaust system. Simply put, the chainsaw begins to smoke heavily and the muffler becomes clogged with carbon deposits, which in turn will lead to a decrease in power.

With an excess of fuel in the mixture, engine parts are poorly lubricated and premature wear occurs. Also, a poor-quality mixture can cause the engine to jam due to overheating (this is one of the reasons why the chainsaw will not start).

It looks like a jammed, overheated piston, from a disassembled chainsaw with an incorrectly tuned carburetor.

Adjustment is necessary when the engine does not idle, stalls, or does not develop full power. Carburetor tuning should be done with clean air and fuel filters. We also recommend reading an interesting article that tells in detail about the main reasons why the chainsaw starts up and immediately stalls.

The main components of the carburetor are:

  • Housing. Made of aluminum for lightweight construction, it has a one-piece shape. The housing contains a diffuser, an inlet connection, an impulse channel, a main screw and an idle screw, a damper that regulates the air supply, and other elements.
  • Diffuser. Located at the carburetor inlet.
  • Jets. Special valves by means of which the amount of fuel is regulated.
  • Spray.
  • Float chamber.

Chainsaw carburetor device

Almost all chainsaw models use an identical carburetor design. As an exception, the carburetor of some very cheap Chinese chainsaw can be called. some parts may not be there, and most of the nodes are made from very cheap materials.

Chainsaw carburetor: device, principle of operation, malfunctions, maintenance and repair

Any chainsaw is equipped with a two-stroke single-cylinder carburetor engine. Early models of chainsaws were equipped with contact ignition, but now almost all manufacturers use electronic ignition, so you do not need to constantly clean the contacts and adjust the gap between them.

The air-fuel mixture is mixed in the carburetor for engine operation. With the help of a special flap, you can manually deplete or enrich the fuel mixture for a specific purpose. for example, for cutting hardwood.

Both the serviceability of the engine and the performance of the chainsaw directly depend on the good technical condition of the carburetor. Let’s take a closer look at how the chainsaw carburetor works.

An approximate diagram of a chainsaw carburetor

How to properly adjust the carburetor on a chainsaw with your own hands

Chainsaw carburetor factory settings provide optimal parameters for fuel and air intake. But in the process of work, they can get lost due to vibration. a shift of even ¼ of a turn for any of the screws can lead to a serious change in the parameters of the preparation of the air-fuel mixture and it is necessary to adjust the carburetor of the chainsaw.

The carburetor of the chainsaw is adjusted using three screws marked H (High), L (Low) and S. The last screw, depending on the brand and manufacturer, may have other names, for example T or LA.

  • H: responsible for the operation of the main jet and regulates the maximum speed.
  • L: adjusts the position of the idle jet and allows you to adjust the low speed.
  • S / T / LA: intended to adjust the idle speed of the motor.

To know how to properly adjust the carburetor on a chainsaw, a technical data sheet is required. it contains information about the angles of rotation of the adjusting screws. After that, we go directly to the adjustment. By the way, here you will need a screwdriver to adjust the carburetor of the chainsaw or an ordinary flat screwdriver:

  • Place the chainsaw on a flat surface, preferably a table or something similar.
    IMPORTANT: The chainsaw must be positioned so that the tire points in the opposite direction. The engine must be turned off.
  • Using a wrench or screwdriver, unscrew the fasteners of the housing cover and remove it to get to the carburetor.
  • Remove the air filter that covers the chainsaw carburetor. The manufacturer can install a shock absorbing foam insert on top of the carburetor. it must also be removed.
  • Now the tuning of the chainsaw carburetor begins. Screws L and H must be tightened up to the stop. Twist them slowly and carefully so as not to break.
  • Unscrew both screws approximately 1.5 turns.
  • Start the engine and let it run for about 7-10 minutes so that it warms up well. on a cold engine it will not work to adjust the carburetor of the chainsaw.
  • After the engine has warmed up, set it to work at medium speed.
  • Slowly begin counterclockwise to tighten the idle screw. You need to twist until the motor runs smoothly. If the engine starts to stall, you need to continue adjusting the carburetor of the chainsaw and gradually return the screw clockwise.

After the carburetor of a Chinese-made chainsaw or any other has been adjusted, it is necessary to “drive” the motor at different speeds.

The main malfunctions of the carburetor on a chainsaw

It should be understood that the dimensions of all the holes are very small. Even the smallest contamination can block the flow of air or fuel, which is why filter elements are installed at the inlets. Unfortunately, they do not always cope with the task at hand. Chainsaw carburetor malfunctions are indicated by the following symptoms:

  • High gas mileage and thick exhaust smoke;
  • The engine does not pull;
  • Floating revolutions;
  • The motor starts, but stalls immediately or after a few seconds;
  • The motor does not start at all.
  • The chainsaw shoots the carburetor

All these malfunctions are a sign of a violation of the carburetor adjustment on the chainsaw, or it is dirty. Hence the need for adjustment, cleaning or repair. How to do this. we will consider below.

How to remove a carburetor from a chainsaw?

Either the engine does not start or immediately stalls, most likely the carburetor is clogged and needs cleaning. How to check a chainsaw carburetor? We’ll have to disassemble. otherwise it will not work.

Before cleaning the carburetor on a chainsaw, it is still recommended to check other components: air and fuel filters, spark plug and muffler. It is possible that it is they who are clogged. it is easier to clean the filter or replace the plug than to clean the carburetor on a chainsaw. By the way, it is the problem with the candles that is the reason why the chainsaw shoots at the carburetor. too late ignition leads to the fact that an excess of the air-fuel mixture is formed, since it does not have time to burn completely.

If the problem persists, the carburetor will have to be removed. It is very easy to do this:

  • Remove the plastic back cover. it is held on the latch or on the thread.
  • Dismantle the air filter.
  • Use a flat screwdriver to pry on the air rods and remove them. There can be two or three rods, depending on the model.
  • The carburetor is attached with two mounts. they are located diagonally. You need to unscrew them.
  • Disconnect the gasoline hose that supplies fuel to the carburetor from the gas tank.