Gasoline for a chainsaw: which one to choose and why mix it with oil?

The gasoline engine drives a metal chain with a large number of cutting “teeth.” They rotate at high speed around the guide bar. As the chain contacts the log or tree trunk, its teeth run along the surface, cutting the wood. The circular motion of the chain keeps the teeth in contact with the wood, so the saw continues to cut until the job is done or the chain stops.

Most gasoline saws have two-stroke engines, which are similar to the models used in mopeds or boats. They are similar to each other in the principle of operation. It is worth keeping in mind that the engine of a gasoline chainsaw will require regular maintenance to keep it in working condition.

Chainsaw fuel system design

Most modern chainsaws are powered by a single-cylinder, two-stroke internal combustion engine running on 92 octane or 95 octane gasoline . Old domestic models must be fueled with 80 octane fuel.

In order to facilitate the design, hand chainsaws are not equipped with a gearbox.

The rotational speed of the chain drive is determined by the speed characteristics of the motor, which usually exceed 10,000 rpm. Therefore, the fuel mixture for a chainsaw equipped with a high-speed engine must contain special motor oils.

The chainsaw fuel system includes:

• filling tank;
• fuel filter;
• carburetor;
• hoses through which fuel is supplied to be mixed with air and then into the engine cylinder.

The fuel filter is attached to the end of a hose that runs into the tank. When the engine is running, uninterrupted pumping of fuel is ensured by a small pump built into the carburetor. To start the engine, mechanical pumping of gasoline is required with an additional device - a primer. A special air valve protects the tank from creating a vacuum when the liquid level decreases during operation. The carburetor is responsible for the correct ratio of fuel to forced air in the process of creating an air-fuel mixture that is supplied to the cylinder for combustion. The entire fuel system works in concert with the ignition system in time with the movement of the piston.

How to choose oil to lubricate a chain or motor

A good lubricating mixture extends the life of the chainsaw and guarantees high quality work. For a new tool, it is recommended to use Stihl branded chain oil recommended in the instructions. Otherwise, the chainsaw may be removed from warranty service due to non-compliance with operating conditions. At the end of the warranty period, you can use any other brand of oil. It is worth remembering that it needs to be replaced twice a year.

Stihl has developed a whole line of lubricant mixtures for two-stroke engines. High cleaning ability will improve the environmental friendliness of using your tool.

All synthetic oils are made on the basis of primary raffinates, which can reduce the amount of emissions and prevent damage to the moving elements of the chainsaw during continuous operation.

STIHL HP oil

- made on a mineral basis and has excellent combustion and lubrication properties. Available in various volumes from 20 ml to 55 l.

HP Ultra Oil

- Suitable for long-term use of the tool. Ensures complete combustion of the fuel mixture and thoroughly lubricates the necessary components. It has a high degree of decomposition - more than 80% in 21 days.

Engine oil SAE 30

— used for any operating conditions in the garden. Helps reduce fuel consumption and is characterized by high-quality base oils.

Engine oil 10 W-30

— designed for 4-stroke engines. Resistant to temperatures up to – 30 °C.

Gasoline in a chainsaw

Many people know the saying: “We are what we eat,” and it’s the same with technology. Filling with low-quality fuel will certainly affect the operation of the tool. Fuel consumption increases, engine power decreases, parts wear out faster.

What requirements must gasoline meet in order for the chainsaw to operate without interruption:

— gasoline should not contain alcohol (unleaded);

— gasoline in a chainsaw must have a high octane number;

- Gasoline for the chainsaw must be fresh.

These characteristics affect the traction properties of the engine and the duration of its operation.

Before choosing one or another type of fuel, carefully read the operating instructions. Most often there are clear instructions on the choice of fuel.

To refuel modern chainsaws, AI-92 gasoline is used; these characteristics are considered optimal for this type of engine. Some advanced users recommend using AI-95 gasoline, supposedly it is of better quality. Experts do not recommend doing this. The fact is that the octane number of gasoline, in this case, is obtained with the help of various impurities and additives, the quality of which raises many questions.

Adviсe

Tips and life hacks can be extremely useful in practical work, let's look at some of them:

1. It is convenient to use cans with dispensers, and experienced people filter gasoline through suede. The cleaner the fuel, the better the carburetor will work.
2. Gasoline can actively evaporate, especially at high temperatures; a suspension forms at the bottom of the canister, which cannot be poured into the engine.
3. It is recommended to prepare fuel for no more than three operational refuelings.
4. The quality of the fuel can be affected by the material of the container; PVC materials react especially actively.
5. If the combustible mixture was poured of poor quality, the chainsaw may be void of warranty.
6. During operation, you should test the tightness of the containers and the rhythmic operation of the engine.
7. One of the first signs of a malfunction is undue heating of the circuit.
8. Before subjecting the tool to serious loads, you should test it at idle speed.
9. The tank lasts for half an hour when working.
10. There is still lubricant (residues) in the second container when the reservoir runs out.
11. If a large amount of smoke appears during operation, this means that the fuel is of poor quality.
12. While the unit is operating, do not approach open flames.
13. (distance up to 2 meters).
14. You should not fill the fuel “under the rim”; leave a little space.

Advantages and disadvantages of oil

Any high-quality machine oil has its pros and cons.
Any high-quality engine oil has its pros and cons . Some experts say that any chainsaw oil will do. This is not entirely true; almost any substance can be used for the Khurstavna chainsaw, but only gear oil is required for the Shtil chainsaw. When choosing, you need to know the color of the oil well; a two-stroke engine requires a composition that has a reddish, bluish or greenish tint.

To prepare the mixture yourself, you need to use a heat-resistant lubricant that has a well-known brand.

The density of the product is affected by seasonality:

• Air temperature.
• Humidity.

• Solar radiation intensity.
• Pressure.

what the features of different oils are by carefully studying the label on the container. If there are no instructions or labels on the package, you should refuse to use such a substance. At the same time, the performance characteristics of oils should not change dramatically when temperature conditions change.

You should not use any substitutes; counterfeit products are often found among them (up to 20%). It is quite difficult to distinguish a fake; you need special equipment.

It is recommended to store fuel in metal containers. It is best to prepare the fuel mixture in a canister.

There are a large number of oils and each has its own characteristics

The consistency is made in the ratio:

The performance characteristics of mineral or organic oil intended for the chain itself are not suitable for preparing the fuel mixture. The container is filled with the finished product (up to half), then mixed (the container must be hermetically sealed). Thus, a homogeneous composition is obtained. It is better not to prepare the fuel ahead of time; it quickly loses its functional properties. At room temperature, flammable liquids deteriorate within two weeks.

Fuel consumption

One of the most important questions that arises among owners of saw tools, because everyone wants to know what to expect.

The volume of almost all tanks is approximately 500 ml. If the power of the chainsaw is 2 kW, then the consumption of the fuel mixture will be approximately 1.2 liters per hour of operation. To put it simply, such a tool will be able to work at maximum speed for half an hour without a break. If the chainsaw is not so powerful, then its tank volume will be smaller. This way the user can independently control fuel consumption.

Over time, the user will learn to service his tool without any help. The main task will be to maintain the economic unit in good working condition, using high-quality fuel mixtures. Follow safety rules when preparing flammable liquids. This will help preserve the instrument and not harm yourself and the environment.

Storage recommendations

The mixture must be prepared in the quantity necessary to carry out a small amount of work, since when the solution is stored for a long time, its quality characteristics deteriorate. The prepared mixture must be consumed within several days.

A fuel mixture that has been stored for about a month will reduce engine performance. Resinous substances are formed in the nodes, and carbon deposits appear, the piston rings lose mobility. The longest shelf life of the mixture is no more than 2 weeks. During this period, the solution will not lose its quality. If the air temperature is more than +25ºC, then the shelf life of the product is reduced to 10 days.

Recommended sequence

In accordance with the standard technology for producing a fuel mixture, the calculated amount of oil is poured into a tank half filled.

The mixture is thoroughly mixed with the plug closed, after which the remaining gasoline is poured. This sequence contributes to the homogeneity of the acquired composition.

It is better to prepare fuel for a chainsaw in quantities sufficient to perform one-time work. The finished composition can be stored at a standard temperature of 20°C for less than 1 month. At higher temperatures, the shelf life is reduced to 2 weeks.

An expired mixture initiates the formation of resinous compounds, which contribute to clogging of the jets, the formation of carbon deposits and limiting the mobility of the piston rings. In order to save money, the overexposed composition can be consumed by adding up to 15-20% of the total volume to the freshest mixture.

Proportions of gasoline and oil

Due to the two-stroke type of engine, fuel is purchased separately in its pure form, and then mixed with oil intended specifically for this engine version. Most experienced users mix substances in proportions of 1:50. In the photo you can see popular high quality products used to prepare the fuel mixture.

Important points to observe:

• domestic chainsaws (Ural, Shtil, Druzhba) work with an oil component of the M8-V, M-12TPU, M8-V, TP, MGD-14M brands, sometimes foreign versions can be used; recommended proportion – 100 g of oil per 2.5 liters of AI-80 gasoline;
• foreign models (Husqvarna, Partner) operate on foreign-made oils (1:50 or 1:40) and are characterized by a minimum consumption.

Most Common Circuit Problems

How to adjust the oil supply to a chainsaw chain?

If the oil supply to the chain is incorrectly adjusted, the chain may overheat (insufficient supply) or increased oil consumption and contamination of the wood with oil (too much supply). Therefore, adjusting the oil supply to the chainsaw chain is a very important process, since both the consumption of the oil itself and the long-term operation of the chainsaw itself depend on it.

How oil is supplied to the chainsaw chain depends on the position of the oil pump plunger adjustment screw. The factory setting is for the screw to be in the middle position. To reduce the oil supply, you need to turn it o, to increase it - to o.

How long does gasoline last?

During long-term storage, gasoline evaporates (regardless of the brand), sediment forms at the bottom, it loses its properties, in other words, it deteriorates. It is worth knowing that it is not so much the gasoline itself that ignites, but its vapor. Therefore, if there has been a can of gasoline in the garage since last year, then think, is it worth it? Better leave it to light the fire for the barbecue.

Using “stale” gasoline for a chainsaw entails many problems:

• difficult starting;
• reduction in maximum power;
• increased wear of chainsaw engine parts.

It is worth remembering that the prepared fuel mixture (gasoline and oil) can be stored for no more than a month; after this time it should be disposed of. Using an old mixture increases wear on chainsaw engine parts - don’t forget about it!

Good to know

Fuel must be prepared for 3 refills. After all, storing a large amount of fuel can negatively affect the operation of the chainsaw. The mixture can behave differently, because it will be influenced by many factors. As a result, your household unit may suffer serious damage, which will entail financial costs.

Sometimes even the container can affect the quality of the liquid. Plastic and glass react with gasoline, creating a flash fire hazard.

It is important to remember that if the chainsaw breaks down due to poor-quality or incorrect mixture, it will not be possible to repair the unit under warranty.

The finished liquid cannot be stored for more than a month, because the oxidation process occurs. After working with a chainsaw, you need to use up the remaining fuel, turn off the engine and remove the remaining fuel mixture.

Proportions of oil and gasoline for chainsaws

There are only 3 ways to mix oil. But to implement any of them, you need to correctly measure the components so that the mixture acquires the required technical qualities. Basic proportion options:

• 1/15;
• 1/20;
• 1/25;
• 1/40;
• 1/50.

In terms of milliliters, 1/50 will correspond to 20 ml of oil per 1 liter of fuel. Others are calculated similarly. It is not recommended to choose them at your own discretion and measure them by eye. You should strictly follow the instructions on the oil packaging or included with the tool. If they do not coincide with each other, priority should be given to the one that comes with the saw. You also need to mix them with knowledge of technology. You need to add oil to fuel, and not vice versa. It has a denser structure than gasoline and can stick to the walls of the container, whether it is a separate mixing container or just a fuel tank. To obtain the correct mixture, you need to use measuring instruments:

• graduated measuring cups or bottles;
• medical syringes without needles;
• special branded containers for mixing.

Features of preparing the mixture

For safety reasons, it is recommended to prepare the fuel mixture in a metal canister that is not subject to the formation of static electricity.

• The recommended proportions of gasoline and oil are individual for each model. In most options, this is a ratio of 50:1 and 40:1. Much less common are chainsaws that run on a gasoline-oil mixture in a ratio of 25:1.
• According to manufacturers of branded chainsaw equipment, their products do not require running-in. However, during the first hours of operation, experts advise operating a new chainsaw on a fuel mixture with a high oil content and, if possible, in a gentle mode.

Containers with built-in dispensers are convenient for preparing the working mixture. The selectivity of fuel filters at gas stations, in some cases, leaves much to be desired, so it is recommended to filter gasoline through suede or non-fiber material.

Following these recommendations will eliminate spontaneous equipment failures associated with malfunction of the carburetor.

The specific characteristics of mineral or organic chain oil are aimed at lubrication and cooling of saw accessories, and therefore are not suitable for preparing a fuel mixture.

Running the tool

Starting a chainsaw, especially the first time, is a rather difficult and important step. To ensure everything goes correctly, follow the instrument manufacturer's instructions exactly.

When working with a chainsaw, be sure to use personal protective equipment.

Before you start working with a chainsaw, you should take care of your own safety. First of all, do not neglect personal protective equipment: a thick jacket, safety glasses and reliable closed shoes will be useful. They will protect against dust and small chips that fly in different directions during intensive work.

While working, you should not be distracted, and if there is a need to step aside, the tool should be turned off. The chainsaw is held with both hands, while your back must be kept straight and not slouched. The chain is only driven when sawing wood.

If during work it is time to refuel the tool, then you need to wait until it cools down. Under no circumstances should you pour fuel into a hot engine - this can create a fire hazard. All refueling operations should be carried out at a safe distance from the work site - about 5-6 m.

To carry out activities such as felling trees, make sure there is a free space around that is free of unauthorized people or buildings.

Benefits of branded oils

You can also find branded oils on sale, which are characterized by their specific performance characteristics.

The advantages of branded oils include the following points:

1. Higher quality.
2. Increased lubricating properties.
3. Can be used to refuel most foreign chainsaws.

However, increased characteristics determine that the product of foreign manufacturers has a higher cost. That is why many, in pursuit of savings, try to refuel their foreign chainsaws with a product from domestic manufacturers, making a serious mistake.