How to Know the Fuel Consumption of a Chainsaw

How TO CONFIGURE a carburetor on a Husqvarna 135 chainsaw. Related Entries

Carburetor adjustment Husqvarna 372 XP, 365

Adjusting the carburetor of the Husqvarna 372 XP chainsaw means adapting the engine to local conditions, for example, climate, altitude, gasoline quality and type of oil for two-stroke engines.

The carburetor is equipped with three control options:

L = low speed jet. H = high speed jet. T = Screw to adjust idle speed.

Likers L and H control the amount of fuel that matches the flow of air supplied by the throttle.

If the nozzles are screwed clockwise, the mixture will be poor (less fuel in relation to the amount of air), and when unscrewing, the nozzle will be richer.

A poor mixture produces higher speeds, while a richer mixture gives lower speeds. Screw T adjusts the shutter idle.

If the screw T is turned clockwise, the number of revolutions, and if you turn the arrows, the number of revolutions will decrease.

Presetting and starting the Husqvarna 365 XP chainsaw

When checking factory operation, the carburetor was pre-adjusted. Preliminary adjustment: N = 1 revolution, respectively L = 1 revolution.

To make sure that the parts of the Husqvarna saw engine are sufficiently lubricated (pumped), the carburetor is installed with a slightly higher enrichment of the fuel mixture during the first 3-4 hours of operation.

How to Know the Fuel Consumption of a Chainsaw

For such an installation, the maximum speed is set at 6-700 rpm below the recommended speed.

If it is not possible to check the maximum number of revolutions with a tachometer, then the H stream should not be installed on the preset.

Do not exceed the maximum speed. If the chainsaw chain is idling, turn screw T counterclockwise to stop it completely.

How TO CONFIGURE a carburetor on a chainsaw. Chainsaw carburetor device

To independently adjust the carburetor of the chainsaw, you do not need to be a professional motor technician. However, you still have to learn some aspects of the carburetor operation related to the process of preparing the fuel mixture.

The vast majority of chainsaws are equipped with Chinese-made Walbro carburetors. In their device they are simple, if not primitive. There is a one-piece block-type housing with a through hole. Inside the hole there is a diffuser. Narrowing the passage with the fuel injection channel. There are dampers on both sides: the smaller one is the throttle, it controls the amount of fuel mixture to be fed into the cylinder. A larger damper. Air, serves to limit the flow of air during a cold start.

Walbro carburetor device: 1. Inlet fuel fitting; 2. Pulse channel of the diaphragm pump; 3. Inlet valve; 4. A membrane of the fuel pump; 5. Exhaust valve; 6. Filter mesh; 7. Air damper; 8. Throttle valve; 9. A fuel channel; 10. Idle adjustment screw; 11. A needle; 12. Idle jets; 13. A control membrane; 14. A fuel chamber; 15. Main jet; 16. Diffuser; 17. The main adjusting screw

All the magic of fuel preparation takes place in the hidden channels and chamber of the diaphragm pump. When the throttle is turned, the cross-section of the channel through which fuel is injected into the mixing chamber increases slightly and fuel enters in a larger volume. At the same time, the carburetor has two kind of valves: for feeding at low and high speeds. When changing the throttle position, the fuel flow changes proportionally between these two valves.

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The need for such a device is that at idle and under load, the quality of the mixture should be different. At the same time, the channel through which fuel is fed into the mixer at idle does not completely overlap during engine acceleration, and vice versa. The maximum speed channel is slightly corroded at idle.

How TO CHANGE a carburetor on a Partner-350 chainsaw. Description and Specifications

The Partner 350 chainsaw is an example of an excellent saw workshop, suitable for performing various kinds of work on a personal plot, harvesting firewood, etc. Compared to, then Partner 350 is very necessary when it comes to periodic use at low load levels.

It is important to note that the unit has a chrome-plated inner surface of the working cylinder, which allows to significantly extend the life of the device. This chainsaw has a good air purification system, CCS marking. In other words, it will be said that an air purification system is involved in the unit, which is based on the principle of a conventional centrifuge.

After cleaning, the air prepared for work will enter through a special filter into the carburetor. If you are interested in setting up the carburetor of the Partner 350 chainsaw, then we inform that it is easy to disassemble and clean it yourself. To adjust the carburetor, simply add air to the system and let it run for a minute in the empty. Then gaz a few times in a row, but slowly. Look

If there are “failures” in dynamic operation, then you will need to unscrew the L-screw L by ¼ of its revolution and re-check everything. As you can see, adjusting the carburetor of the Partner 350 chainsaw with your own hands is possible and it is of particular difficulty.

Partner 350 chainsaw device

Partner 350 chainsaw device is quite simple to understand. If you are a beginner, and don’t know how to cut trees with a chainsaw, go. To fully understand the scheme of operation of this unit, we suggest that you familiarize yourself with the user instructions in detail.

Partner 350 Chainsaw Features:

  • Household type saw;
  • Equipped with a two-stroke engine of a single-cylinder type;
  • The specific power of the system is 1.8 hp. (1.3 kW);
  • Cubic volume of the engine. 36 cm;
  • Start type. Manual;
  • Fuel volume. 400 ml;
  • Oil volume. 200 ml;
  • Type of cooling system. Air;
  • Maximum idle speeds up to 4000 rpm are characteristic;
  • Working tire length. 0.4 m;
  • Chain step. 3/8;
  • Type of fuel used for work. Gasoline oil;
  • Nominal weight about 4.7 kg.

How TO CONFIGURE a carburetor on a Stihl chainsaw. How to properly adjust the chainsaw carburetor

A chainsaw is a technically sophisticated tool that needs to be serviced from time to time. Cleaning, replacing filters and, of course, adjusting the carburetor of the chainsaw will help to serve the entire life set for it. In this article, we will consider the issue of carb settings. How and why it is carried out.

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Situations in which adjustment is necessary

New chainsaws are supplied from the manufacturer with adjusted carburetors. This is called standard adjustment. But for normal passage, the process requires lowering the maximum engine speed, adjusting 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 increased fuel consumption, which negatively affects the operation of the exhaust system. Simply put, the chainsaw begins to smoke very much and the muffler becomes clogged with carbon, which in turn will lead to a decrease in power. With a lack 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).

Adjustment is necessary when the engine does not keep idle, stalls or does not develop full power.

The carburetor must be adjusted with clean air and fuel filters.


Correct adjustment of the carburetor of the chainsaw should be carried out using a special tool. A tachometer. It allows you to most accurately determine the maximum number of engine revolutions and adjust them according to the requirements of the manufacturer. To adjust, you need to have a small slotted screwdriver. For some models of chainsaws, you will need a special adjustment key, without which it is impossible to carry out work.

The key for adjusting some carburetor models is available only in service centers authorized by the manufacturer for the repair of chainsaws. This measure is aimed at reducing damage due to improper settings by inexperienced users and those involved in the repair, without official permission to do so.

Setting up the chainsaw should, if possible, be carried out in official service centers that have a certificate from the manufacturer.

How to adjust the carburetor

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

  1. Adjustment of the engine for smooth operation at low speeds.
  2. Setting the carburetor to the correct flow of the fuel mixture at maximum speed.
  3. Fine carburetor adjustment for idling.
  4. Checking the chainsaw in all modes.

The carburetor must be adjusted after the engine has run a little and warmed up.

Now we will consider how the correct adjustment of the carburetor of the chainsaw goes in more detail. 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. The screw (L) controls the formation of the mixture at low speeds. By tightening the screws (L) and (H), the fuel supply and the mixture are leaner, respectively, revolutions increase.

Process description

If the carburetor of the chainsaw is not adjusted, and it is not possible to start the chainsaw, then the setting is started by setting the screws (L) and (H) to the standard setting. This is 1/5 turn of the screws until fully tightened. After which, it is necessary to start the engine, let it run for a bit and warm up. The next step is setting the low speed mode. Optimum engine operation at the “bottom” can be achieved by adjusting the screw (L) and idle speed (T). To do this, first screw (L) is tightened until the maximum engine speed is obtained, then it is released by 1/4, and the screw idle is normalized by screw (T).

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After adjusting the work on the “bottoms” is the adjustment of traction and maximum engine speed. To do this, slowly tighten the screw (H) and check the speed using the electronic tachometer.

Exceeding the maximum engine speed declared by the manufacturer is unacceptable.

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

Loss of traction at maximum speeds recommended by the manufacturer is an indicator of CPG wear or poor fuel quality.

Carburetor adjustment for Chinese chainsaw

Carburetors mounted on Chinese-made saws are made similarly to European ones and have the same tuning screws.

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

The setting of the carburetor of the saw can be studied in the below. In this, the wizard shows how the step-by-step adjustment of a Chinese-made chainsaw is performed without using a tachometer. Carries out after adjustment check in various modes.

Adjusting the carburetor of the chainsaw, although it seems a fairly simple process, but requires a very careful and responsible approach. The article describes the process in sufficient detail, however, if you have never regulated a chainsaw, it is worth contacting specialists, this will help save time, nerves and money.

How to adjust the chainsaw carburetor. Service

How TO CONFIGURE a carburetor on a chainsaw Champion. Husqvarna Saw Carb Adjustment.

For the break-in mode, so that the parts receive sufficient lubrication, the carburetor of the Husqvarna chainsaw is configured so that the maximum speed is 600–700 rpm. Lower than working. If it is not possible to set the operating maximum frequency according to the tachometer, it is not worth changing the default settings with screw H. Exceeding the maximum speed value by the manufacturer is prohibited. If, after completing the adjustment, when the engine is idling, the saw chain moves, turn the screw T counterclockwise to force it to stop completely.

For precise adjustment, the saw must be warmed up for at least 10 minutes, installed on a flat surface. The tire should be pointing in the opposite direction from the person performing the tuning. At the initial stage, the highest value of the idling frequency should be detected. Setting up the carburetor chainsaw performed in the chainsaw should work. To do this, screw L is smoothly turned first from left to right, then vice versa. When the maximum revolutions are found experimentally, the screw L must be turned counterclockwise by a value from 1/8 to a quarter of a full revolution.