Not so long ago, a chainsaw was considered a real luxury, as it was expensive and was used only by professionals. Today, this tool can be purchased by everyone. Household models appeared on the market that are lightweight and have a limited set of functions.
A modern chainsaw operates through a single-cylinder two-stroke carburetor engine. Previously, models of such equipment were equipped with contact ignition. Today, almost all manufacturers are introducing electronic ignition. Due to this, there is no need to adjust the gap between the contacts and constantly clean them.
What is a carburetor for?
For engine operation, the air-fuel mixture is connected in a carburetor. A special flap allows you to manually enrich it for certain tasks, for example, for working with solid wood. The operability of the engine and the productivity of the tool itself depend on the technical condition of the carburetor and its serviceability.
Device
Before starting operation, it is necessary to consider the device and the principle of operation of the carburetor of the chainsaw. Almost all models use parts that have an identical design. The exception is the carburetors of Chinese equipment. They may not have some spare parts, and a number of nodes are made of cheap materials. Among the main components of the carburetor should be highlighted:
- Body.
- Diffuser.
- Spray.
- Jets.
- Float chamber.
As for the case, it is made of aluminum to facilitate the design. It also has a solid mold. Inside there is a diffuser, a pulse channel, an inlet fitting, an idle screw, a main screw, and also a damper. The latter is necessary to adjust the air supply.
Present in the case and other elements. Considering the device and the principle of operation of the carburetor for the “Partner” chainsaw, you can notice that the described element of the device also has a diffuser, which is located at the inlet. Special valves are jets. They serve to adjust the amount of fuel.
Principle of operation
Before you start adjusting the carburetor, you need to understand the principle of its operation. When the engine starts, the air damper at the bottom of the housing opens. A vacuum occurs in the float chamber and the air channel. It is caused by the stroke of the piston. This helps to ensure that the airflow is drawn in through the diffuser.
The principle of operation of the Husqvarna chainsaw carburetor is exactly the same. With this instrument, the air intake rate is adjusted by the position of the air damper. Through the inlet fitting from the tank, gas enters the float chamber. Using the nozzles, the speed of fuel passage into the diffuser is adjusted. There it mixes with air. The prepared composition is in the inlet channels. From there, he goes to the cylinder combustion chamber.
What else do you need to know
The principle of operation of the carburetor chainsaw "Calm" is the same as that of the above model. Additionally, it can be noted that the needle is responsible for injecting fuel into the float chamber. The more fuel, after mixing with air, enters the engine, the higher the engine speed will be.
Regardless of the chainsaw model and manufacturer, modern tools are usually equipped with carburetors that have an identical design. They work, respectively, on the same principle. The main difference is only in the arrangement of nodes in the carburetor device and spare parts materials.
Features of the chainsaw, indicating the need for carburetor adjustment
The principle of operation of the carburetor of the Partner chainsaw is now known to you. This helps to understand how to adjust. It is necessary when some difficulties appear in the operation of the tool. The standard new chainsaw has factory settings according to which fuel is supplied. However, for proper break-in, the maximum engine speed should be limited.
Adjusting screws will help in this matter. They are located on the carburetor body. Fine tuning of the flow of the combustible mixture is carried out after break-in. The carburetor is also subject to adjustment with strong vibration. Some operational problems indicate this. If the internal combustion engine immediately stalls or starts poorly, this unit requires debugging.
Sometimes it happens that the engine starts up, but develops revolutions reluctantly or stalls. Having studied the principle of the carburetor chainsaw "Calm 180", you will begin to understand that in the process, the piston group may wear out. In this case, adjusting the carburetor may help, but it will only become a temporary measure.
What else could be the malfunction
During operation of the device, it will be noticeable that the engine does not work at idle or there is an increased consumption of gasoline. Because of this, the unit emits a lot of smoke, the muffler becomes dirty, and the candles are covered with soot. All this helps to reduce engine power. Your actions should be to adjust the carburetor.
Preparation for adjustment
When you become aware of the operating principle of the chainsaw carburetor, you can adjust it. For the correct setting, you need a technical passport, where you can get acquainted with the rotation angles of the adjustment screws. You will definitely need a screwdriver. You can take a special one, designed for adjustment, or ordinary.
The tool is mounted on a flat surface. It could be a table. The equipment must be positioned so that the saw bar is pointing in the opposite direction. The motor must first be shut off. Using a screwdriver or a wrench, unscrew the fastener that holds the cover of the housing cover. It must be removed, which will allow you to get to the carburetor.
Now you can remove the air filter, which closes the node you need. Sometimes a shock-absorbing foam insert is installed on top. It should also be removed. Now you can do the setup itself. The screws should be rotated carefully so as not to break them. The first are usually the L and H screws, which are loosened a half turn.
Customization Features
This procedure can be performed correctly only under certain conditions. For example, the cleaning filter must not be dirty (this applies to air and gasoline). Valves and nozzles must be clean and membranes free of damage. You must also make sure that the needle valve is working. It is also important that the required amount of fuel enters the float chamber.
Specialist advice
The principle of operation of the carburetor of the Chinese chainsaw has been described above. During the operation of the equipment, you can understand when it requires debugging. Before starting this work, you need to warm up the engine at minimum or idle speed for 15 minutes. Using the L control, you should be able to idle around 2000 rpm. It is important to pay attention to how the engine picks them up. Acceleration should occur quite quickly when exposed to the accelerator lever.
If you notice a speed failure, you need to unscrew the screw a little to eliminate this phenomenon, as it is caused by insufficient fuel enrichment. The principle of operation of the carburetor of the Partner 350 chainsaw will allow you to understand how to configure this unit. For example, when the mixture flow is adjusted at low speeds, it is necessary to tighten the screw T. Do this until you notice the rotation of the chain. The screw is then twisted half or a third.
It is important to monitor the coupling mechanism. At idle, the saw should not rotate. This is the norm. Using screw N, it is possible to compensate for over or under revolutions that may be caused by a change in fuel, ambient humidity or a change in oil concentration.
The upper setting may fly off when the low RPM is incorrectly adjusted. The principles of operation of the carburetor of a chainsaw will allow you to understand that it is better not to touch the H screw at all if you do not have enough experience. When tuning is done by an incompetent person, there is a risk that a lean mixture will enter the combustion chamber at high speeds. This operation of the engine under load can cause rapid wear of the piston system. All this will lead to a malfunction in the ignition system.
High RPM Adjustment
You can configure the carburetor according to a simple scheme. This is done by unscrewing or tightening the N. screw. This must be done until the engine reaches about 15,000 rpm at maximum speed. Measurements should be made with a tachometer.
Knowing the principle of operation of the carburetor of a chainsaw, you will be aware that under load the frequency of the spark charge can decrease by about 15%. Frequency should be measured with an oscilloscope. This value can vary from 230 to 250 Hz. To comply with safety measures, adjust the internal combustion engine at a slightly lower speed.
If you have a Chinese chainsaw in front of you, its carburetor is configured according to the same principle. There are holes on the case where you need to insert a flat screwdriver to adjust the speed. As soon as you familiarize yourself with the operating principle of this type of chainsaw carburetor, you will know that each hole has its own designation. For example, near the top you can see the letter T, while near the bottom - the letters L and H.
Conclusion
A chainsaw has become an indispensable tool in private households. Its smooth functioning is an important factor for efficient operation. High-quality performance of tasks depends on how effectively the carburetor performs its functions. To understand this issue, you need to familiarize yourself with the principle of operation of this node, as well as know how to properly adjust it.
But initially the chainsaw comes with factory settings. If you do not have enough experience in the matter of adjustment, it is better to contact a service center. As for the period when the chainsaw is still under warranty. After all, if you begin to disassemble the case during this period, then this may lead to the voiding of the warranty.