Chainsaw Ural dilute gasoline for chainsaw

How to measure head temperature and exhaust gas temperature?

chainsaw, ural, gasoline

We will measure, obviously, with thermocouples. Two. One of which must be present inside the muffler, and the other must be pressed against the block head at the point that is most likely to have the highest temperature among other places on the head.

The thermocouple wires are connected to a twisted pair (gray wire in the figures; twisted pairs are used to connect computers to each other, as well as to modems, printers, etc.), and this, in turn, to two digital multimeters.

For the reliability of measurements, for the thermocouple. the exhaust gas temperature sensor. a hole was drilled in the muffler so that the temperature of the gases directly leaving the engine cylinder was measured, and not the gases that passed through the muffler system and partially cooled.

The candle of the tested Ural chainsaw was, generally speaking, a terrible sight:

Overgrown with carbon deposits, which apparently included oil additives. Hmmm Nevertheless, the saw did its job quite tolerably, i.e. sawed. Started up with 1 4 jerks (more on this below). The candle was not specially changed in order to test the possibility of starting the engine and the operation of the chainsaw in somewhat deteriorated technical conditions.

Of course, in the course of the experiments, it would be necessary to measure the useful power, as well as the composition of the combustible mixture but, alas, this is not possible without special laboratory equipment. Therefore, the power was determined “by eye”. depending on the load on the chainsaw and the diameter of the cut wood. And the composition of the combustible mixture. the ability to cut more or less fully (i.e. when the saw does not stall, does not overheat unnecessarily and does not smoke much).

If there is no 80 gasoline, can the 92 be used in two-stroke engines?

Recently, this question has worried. not to say that many, but, nevertheless, a sufficient number of equipment owners. Indeed, sometime, years ago, people (or organizations) honestly, legally acquired technology. Running on 80 gasoline (AI-80). We used this technique legally and conscientiously, took care of it, and repaired it. And, suddenly we got what is called “under the curtain”: the production of the 80th gasoline was discontinued

Experimental results

Now, finally, let’s consider the most interesting thing. the experimental results. The Ural chainsaw was tested when sawing wood (with a diameter of 10 to 30 cm and, sometimes, more), the following mixtures were used as fuel:

Before the next test, the remaining fuel was carefully drained from the gas tank, after which a mixture with a new composition was poured and the tests continued. The tests were carried out in the sequence listed above. In total, the tests took about three days during the period 5 15 July 2019. The oil was used like this, which stood in a plastic container for about 1.5 years.

Diesel fuel was purchased at Bashneft filling stations in July 2019.

Note. And what was the purpose of adding kerosene, diesel fuel (or diesel fuel)? To lower the octane number. The fact is that oil, kerosene, diesel fuel reduce the octane number. We’ll talk about this below.

Is it possible to start and operate the Ural chainsaw on 92nd gasoline?

Oddly enough, yes. Naturally, gasoline should be added with oil in a ratio of about 1:20. However, looking ahead, we will see that you can add not only oil. But more on that later.

So, the third most important criterion is temperature. It is she who determines, on the one hand, the ability to fully operate the engine. On the other hand, it also affects reliability. Namely, if the temperature during engine operation is excessively high, this will contribute to its premature failure. After all, the piston, as well as the cylinder itself, are made of aluminum alloy. The melting temperature of which is in the range of 600 700 0 C. Therefore, at an excessively high temperature, engine parts can, trivially, begin to melt and burn out.

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Is it possible to use some other types of fuel in equipment designed for 80 gasoline?

So let’s talk about this, about the purely technical side of the issue. There are two ways to answer this question:

The operating cycles of these engines are different, the characteristics, technical features are also different. Therefore, of course, one cannot recklessly apply the same thing to both types of such engines. In this article, we will focus specifically on two-stroke engines. specifically, let’s consider whether it is possible to use 92nd gasoline in two-stroke engines, specifically, in the Ural Electron chainsaw. Therefore, below we will mainly talk about it. This chainsaw has a relatively low compression ratio of the fuel mixture in the engine compared to modern chainsaws.

In general, two-stroke engines have not only chainsaws, but also some walk-behind tractors, boat motors, motor pumps, brushcutters, lawn mowers, etc. Where a low engine mass is required, where maximum power per unit of mass is important. there, as a rule, two-stroke gasoline engines are used.

And what is the temperature.

Here we are all talking. temperature, temperature. Which one? Temperature. WHAT? At a minimum, this is the exhaust gas temperature. However, there is also the temperature of the block head. There is also the temperature of the working mixture during its combustion. average and maximum.

Indeed, what is meant by “temperature” in this case? WHAT temperature is most relevant in order to determine the reliability of the engine?

Of course, ideally, you should measure ALL possible types of temperatures, one way or another related to a running engine. The problem, however, is that this will require the use of special laboratory environments. Since, say, it is rather difficult to measure, say, the maximum temperature of an ordinary average Ural chainsaw. Indeed, for this, a highly sensitive and, most importantly, high-speed temperature sensor will have to be placed in the block head somehow. Of course, this can be done. But. Complicated. Especially, for example, in a garage-home. For you will need to drill the block head, use argon welding, etc. And it’s not a fact that after such manipulations the saw will last a long time

One article, as well as many automotive textbooks, deals with at least TWO types of engine temperatures:

It should be noted that these are. in the general case. parameters not related to each other. It may well be that the temperature of the block head is too high, but, on the contrary, the temperature of the exhaust gases is normal. And vice versa.

In a number of other publications, including on the Internet, on the forums, alas, often it is either only about the temperature of the exhaust gases, or only about the temperature of the block head. Apparently, this is a consequence of either a reluctance to understand the issue, or a lack of opportunities for searching and analyzing information.

So, as a criterion for temperature, we take both of those just listed. Let us accept, as a dogma, that if both of these temperatures do not go beyond the permissible limits, then the remaining temperatures and, consequently, the reliability of the two-stroke gasoline engine will also be within the specified limits, i.e. fine.


First, you should outline the criteria on the basis of which we will draw conclusions, whether it is possible to use a chainsaw on 92nd gasoline. It:

The first two criteria are obvious. It is clear that if we cannot start the engine without serious tweaks, if we cannot more or less fully work with a chainsaw, then, naturally, 92nd gasoline will clearly not be suitable.

By reliability we mean the preservation of the operating parameters of the chainsaw engine, in particular, its temperature. precisely, not too much temperature rise during engine operation, when running on 92nd gasoline, compared to 80th.

How to mix fuel for chainsaw

Of course, there are also other factors of reliability, for example, the composition of gasoline (will it corrode the carburetor gasket, for example), the burning rate, the maximum pressure in the combustion chamber, the tendency to detonate, etc. But, the first two three of them are interrelated with temperature. As for the latter. so for this 92nd gasoline is even better than 80th.

Influence of the quality of the fuel mixture on the temperatures of the cylinder head and exhaust gases

Also, studies were carried out to what extent both temperatures are affected by a change in the quality (enrichment / depletion) of the fuel mixture. As a rule, depletion led to an increase in idle speed; but, even after their adjustment (reduction), the temperature of the cylinder head increased quite significantly (by 50% or more). This was especially noticeable for the last mixture (with diesel fuel). When the mixture was enriched, the head temperature at idle speed decreased.

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Whereas the temperature of the exhaust gases, oddly enough, was not too subject to changes depending on changes in the quality of the mixture.

Helpful hints:

The correct operation of your equipment is entirely up to you. First, do not disdain the manufacturers’ pointers or, in extreme cases, the instructions on the oil packaging. This will help avoid unpleasant situations. The neighbor does not always know what is the best way to do it. The cheapness of oil and gasoline is not an indicator of high quality, because a breakdown of a tool can be much more expensive (about 80% of the cost of a chainsaw) than the funds saved on the fuel mixture.

Under the brand

For modern brands, for example, Husqvarna, Partner, Makita, Echo, STIHL, AI-92 gasoline is suitable. Today, just a huge number of people complain about the premature failure of chainsaws due to poor gasoline. Therefore, some experts recommend pouring AI-95 into such chainsaws. At the same time, a good AI-95 can “burn the piston”, and again a certain number of people found a compromise and mix AI-95 with AI-92. In general, it all depends on the quality of gasoline and in the end it is up to you.

For domestic instruments, Ural, Druzhba, it is recommended to take AI-80 gasoline. It is very important that fuel consumption is kept to a minimum.

Making the mixture: important proportions

When using a two-stroke engine, clean fuel is purchased separately and mixed with oil, often in proportions of 1:50. It is structurally impossible to install an oil pump in such an engine, therefore, pouring pure gasoline into the chainsaw is strictly prohibited! The proportions, quantity and some brands are indicated by the manufacturer in the instructions for use.

Important points in the cooking process:

  • Domestic chainsaws work with oil M8-V, M-12TPU, M8-V, TP, MGD-14M. In some cases, you can use foreign options;
  • Proportions: 2.5 liters of FI-80 gasoline per 100 grams of oil;
  • Foreign models are distinguished by minimal fuel consumption. They work on foreign oils, and their proportions become 1:40 or 1:50.

How to breed gasoline for a chainsaw Ural

Preparation of the fuel mixture when working with the MP-5 “Ural-2T Electron” chainsaw

To make fuel mixture huyosen chainsaw

For the running-in period of the chainsaw, use a fuel mixture of gasoline and oil according to 2.3 in a ratio of 15: 1 by volume, i.e. add 1 liter of oil to 15 liters of gasoline and mix the mixture thoroughly. The amount of gasoline and oil in the fuel mixture is shown in table 1.

Hello! Glad to see you again, dear readers and subscribers of Andrey Noak’s Blog. Everyone who has a chainsaw at home already knows exactly what kind of gasoline and how to fill it. But to those who just want to buy such a unit for themselves, the article will seem entertaining.

The chainsaw is one of the most convenient and versatile household appliances. Before use, you need to prepare a fuel mixture. But for the unit to work correctly, you must follow all the manufacturer’s recommendations. Each model is individual, so which gasoline to fill in the chainsaw?

Fuel mixture

To properly prepare fuel, you will need a list of additional tools:

  • Plastic or metal container for diluting the substance;
  • Measuring bottle for gasoline;
  • Dispenser;
  • Syringe;
  • Chainsaw tank.

Some manufacturers, such as STIHL, immediately make measuring containers for a more convenient measurement of the fuel mixture.

Different manufacturers produce oils in different shades. The manufacturer HP produces a red liquid. Oil of a green hue is the premium segment “synthetics”. For your Husqvarna chainsaw, you need to use the correct brand of oil. It is of high value, good quality, and is green or blue in color.

The main thing is to correctly calculate the proportions of the mixture. Excess oil can form carbon deposits on pistons and spark plugs. Excessive gasoline can cause engine damage or piston seizure. Each manufacturer gives its own proportions to models of different power.

To mix the components, you will need the aforementioned additional accessories. Also on sale you can find special canisters with two holes for oil and gasoline. Everything is very simple here, pour in the ingredients, tighten the lid tightly and mix by tilting the container. Glass and plastic bottles can be used.

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The fuel mixture must be free from water or dust.

Fuel consumption

One of the most important questions that arises from the owners of the saw tool, because everyone wants to know what he can count on.

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 interruption. If the chainsaw is not as powerful, then it will have a smaller tank volume. So the user can independently control the fuel consumption.

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

Good to know

Procurement of fuel must be carried out counting on 3 refueling. After all, storing a large volume of fuel can negatively affect the operation of the chainsaw. The mixture can behave in different ways, as it will be influenced by many factors. As a result, your household unit may receive serious damage, which will entail financial costs.

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

It is important to remember that in case of a chainsaw breakdown due to a 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 takes place. After working with the chainsaw, you need to use up the remaining fuel, turn off the engine and remove the remaining fuel mixture.

In order for the chainsaw to serve for a long time and not cause problems with repairs, you need to properly prepare the fuel mixture. Internet forums are replete with questions on this topic. We interviewed experts and compiled a short guide.

To prepare the fuel mixture, use AI-92 or AI-95 gasoline. A lower octane number will not work. Gasoline is not necessarily leaded (otherwise the engine will fail) and not old (octane number can change over time). It is forbidden to use oil for boats and four-stroke engines.

The main issue is proportions. Excess oil will cause carbon deposits on pistons and spark plugs. Excessive gasoline will cause piston seizure and early engine failure. On average, one liter of gasoline is mixed with 20-50 ml of oil. STIHL and Husqvarna, for example, recommend taking 100 ml of oil for 4 liters of gasoline. The specified proportion is optimal for chainsaws up to 1.5 kW. For chainsaws over 1.5 kW of the same brands, use a ratio of 1/50 (100 ml of oil per 5 liters of gasoline). Recommendations from Partner and Jonsered: 1/33 ratio (3.3 liters of gasoline, 100 ml of oil). The supersynthetic oil is added at a rate of 100/1. These figures are approximate. Always use the data given in the instructions for your particular chainsaw model. Trust the numbers on oil labels to a lesser extent.

What to mix? On sale are canisters with graduated marks and two holes. for oil and gasoline. Pour in ingredients, screw on lids and stir by tilting the bowl.

Many people use glass and plastic bottles, baby horns and syringes. Be careful with glass and plastic for static electricity. Make sure that no solid particles or water droplets get into the mixture. Be sure to stir the mixture thoroughly.

Finished fuel cannot be stored for more than 25-30 days, because the oxidation process changes its composition. Engine breakdown caused by overexposed fuel is considered non-warranty. The amount of repairs reaches 80% of the cost of a new chainsaw. After the end of the working season, use up the remaining fuel, turn off the engine, remove the remaining fuel mixture.

Remember, your goal is to create a mixture that will ensure smooth operation of the engine, complete combustion of fuel without the formation of deposits, smoke or scuffing.