Secrets of proper preparation of fuel for a chainsaw

Why do chainsaws need to be filled with a mixture of gasoline and oil?

Why is it contraindicated to fill the unit’s tank with gasoline without oil, and what happens if you make a mistake? The reason for the need to dilute gasoline with oil is that two-stroke engines do not have an oil chamber, like four-stroke engines. The absence of this chamber leads to the fact that the rotating and rubbing metal parts of the engine do not receive lubrication, so the following disadvantages are observed:

The friction force increases, which means rapid wear of parts.
The temperature increases due to the friction force, which also negatively affects the operational life of the internal combustion engine.
As the load increases, there is a significant loss of power and performance.

Oil is added to the gasoline of a chainsaw unit to prevent the development of the above processes. If you pour pure gasoline into the tank of the unit and start the engine, then in a short period of time it will simply overheat and jam. That is why, when purchasing a tool, it is important not only to find out how to start and operate a chainsaw, but also to understand the ratio of gasoline to oil.

Why do you need to dilute the lubricant?

At the very beginning, it is necessary to understand the reason for the dilution of fuel. The mixture used for a chainsaw is diluted primarily to extend the service life of its owner. The instructions for it strictly prohibit operation without diluting gasoline.

The basis of the chainsaw motor is a piston internal combustion engine. It consists only of a cylinder, so it does not have additional systems for lubricating parts. The mixture enters it, settles, lubricates the piston rings and walls. In tools such as chainsaws , oil and gasoline act as a unique lubricating fluid. The mixture extends the service life of all parts.

Mixing technology

In addition, it contains additives that are beneficial for engine performance. It has antioxidant, preservative and other properties, which are also useful for the engine and its parts.

Why you need to adhere to the appropriate proportions when mixing

Having decided on the need to mix gasoline with oil in a chainsaw, you will need to find out why you need to adhere to the appropriate proportions when mixing the fuel mixture into a chainsaw.

If you fill in gasoline with a low oil composition, this will contribute to the development of all of the above consequences - engine overheating, scuffing of the CPG and jamming of the internal combustion engine. Only in this case the internal combustion engine will work a little longer than on pure gasoline.
If you fill the tank with fuel with a high oil content, then this is also dangerous, because in this case, in addition to strong smoke, carbon deposits will be observed on the cylinder walls, muffler and other parts. There will be a decrease in power and a decrease in the productivity of the unit. In this case, the engine will run longer, and if deposits occur, they can be removed.

To eliminate negative consequences, and at the same time increase the service life of the tool, it is recommended to understand how much oil should be added to gasoline for a chainsaw in order to achieve ideal engine operation.

What gasoline is suitable for the tool?

There are different opinions among sawyers regarding the use of appropriate gasoline. Some recommend using AI-92 fuel, others argue that you should use fuel with an octane rating of AI-95.

Now it's time to dot the i's. All chainsaws operate on gasoline with an octane rating of 90 to 95. However, it is recommended to give preference to AI-92 fuel. The exception is when the manufacturer makes a recommendation about which gasoline is best to use.

Interesting to know! To produce AI-95 gasoline, most manufacturers use additives mixed with AI-92.

The most important requirement when using fuel is that it must be clean and free of contaminants.

The ratio of oil and gasoline or how to remember the proportion

The most correct proportion of gasoline to oil is the value indicated by the manufacturer.

If you bought a chainsaw, don’t be too lazy to open the instructions and find the manufacturer’s recommendation on how much oil per liter of gasoline to mix into the chainsaw. These recommendations are present in the technical documentation for the unit. However, many people often lose the instructions, so they have to turn to friends or the Internet for help.

If you don’t know how much oil to add to gasoline when preparing fuel, then you should use universal data. Such data requires compliance with the following ratio - 1 to 50 or 1 to 40.

What does this mean? Let's look into this in detail.

A proportion of 1 to 50 means that for 1 liter of gasoline you need to add 20 ml of oil. A ratio of 1 to 40 is characterized by the use of 25 ml of oil per 1 liter of gasoline. Why are two universal values specified? It all depends on the time of year, so if the tool is used in the summer, then 20 ml of oil is added per 1 liter of gasoline, and if in winter, then 25 ml. It’s easy to remember this proportion; to do this, you can use a marker to write marks on the plastic body of the instrument. Below is a table of the ratio of oil and gasoline for chainsaws. Ratios of 1 to 35, 1 to 30 and 1 to 25 are appropriate for high-power units.

Mixing ratio table

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.

Instructions for making a fuel mixture

Let's find out in more detail how gasoline is diluted with oil. Some tool owners do this - pour clean gasoline into the tank and add the required amount of oil. After this, close the lid and stir. This method of diluting gasoline with oil is incorrect. Instructions for preparing a gasoline-oil mixture are as follows:

You need to take a plastic bottle of equal volume - 1 or 2 liters. You can use a 1.5 liter, but this can cause confusion when adding oil.
Fill the container halfway with gasoline.
Add lubricant. It is recommended to dose the oil using a syringe. It is advisable to use a 5 cc syringe, which will allow you to measure exactly 25 ml of oil.
After adding the lubricant to the container, shake thoroughly.
Add gasoline until the container is full and mix thoroughly again.
The result is a ready-made gasoline-oil mixture for a chainsaw, which should be used within 1-2 weeks.

Many people do not pay enough attention to storing the prepared mixture, and therefore can immediately prepare 5 liters and use it throughout the year. However, this approach is extremely incorrect, since the shelf life of the finished mixture is 15 days. If you are sure that gasoline does not contain alcohol, then you can store the finished mixture longer - up to 3 months. After this, the mixture loses its properties, having a negative effect on the internal combustion engine.

Interesting to know! Make it a rule not to prepare chainsaw fuel in large quantities. It is better to prepare 2 times one liter, than to immediately mix 2 liters, which will remain and will be stored indefinitely.

After combining gasoline with oil, all that remains is to refuel the tool and start using it. When refueling a chainsaw, there are some important points that should be taken into account. We'll look into them.

Advice from experienced people

Bogdan Mikhailovich, 51 years old

14 years of chainsaw ownership experience

Now there is a lot of oil, it is very easy to run into a fake. The point here isn’t even that it’s somehow wrong, it’s just an ordinary mineral water, and you buy it at the price of branded, famous synthetics. Therefore, it is better to buy from official dealers - at least they have normal supplies. Among the companies I can recommend Shtil, Oregon, Husqvarna is also good, but in my opinion, a little expensive. Recently, Zubr began producing its own oils. I tried it - it seems ok, and cheaper, but it’s better not to use it in professional equipment. And for household ones it will do.

Anton, 37 years old

6 years of experience using chainsaws at home

I am surprised to see how not only newcomers to gasoline technology, but also quite gray-haired guys prepare a whole canister of the mixture so as not to have to do it all over again every time. Come to your senses, people, this is a mixture; over time, it separates a little, sediment falls out, and the properties change. it must be fresh. Its maximum shelf life is less than a month. And it’s even better to chat a new one before each session, your hands won’t fall off, it’s a matter of minutes. And then they complain about problems, that the saw is sneezing and all that. Of course, the oil peeled off, the cylinder was rubbed dry, it turned out to be a burr, and then a scuff. For repairs.

How to properly fill a chainsaw with a gasoline-oil mixture

Freshly prepared mixture should be stored in a dark room, but no more than 2 weeks. It is best to mix immediately before using the tool. The refueling procedure is carried out by performing the following manipulations:

Before unscrewing the tank cap, you need to clean the surface, or even better, blow it with a hose from the compressor.
Place the chainsaw on its side with the lid on top. At the same time, keep in mind one important point: refueling should not be done in the wind in order to prevent dust and other contaminants from entering the tank.
Place a watering can on the neck, which will eliminate the possibility of fuel spillage.
Fill the tank, but do it so that there is room left. This is done in order to eliminate the possibility of gasoline leaking when screwing on the cap.
After refueling the chainsaw, be sure to pour oil into the tank to lubricate the chain.

We start the engine and make sure it is functioning properly. The smoke from the chainsaw should come out light in color and in volume only when the speed increases.

Chainsaw Shtil MS 180 – technical specifications

The Stihl MS 180 chainsaw stands out for its solid technical parameters. These include:

power – 2 l. With.;
fuel tank capacity – 270 ml;
tank capacity for filling oil – 260 ml;
possible length of the tire used for work is 30–35 cm;
chain pitch – 3/8 "
assembled weight – 4 kg.

Among the advantages of the model, modest fuel consumption should be noted. When operating under maximum loads, the motor consumes no more than 2.9 l/machine. hour.