Fuel mixture preparation
Two-stroke engines run on a gasoline-oil mixture. The main cause of malfunction is the wrong proportions of fuel mixture or a complete lack of oil in the gasoline. When preparing the fuel mixture, a special oil for two-stroke engines marked “For garden equipment” is used. Do not use oil for boat engines, motorcycles, etc. Gasoline/oil mixture ratio may vary depending on the engine model, oil grade, and gasoline tool manufacturer’s recommendations. For two-stroke engines use a mixture ratio of 50:1, 32:1 and 24:1.
Under conditions of insufficient lubrication or when running on pure gasoline, the engine can run for quite a long time. Prolonged use of pure gasoline is often characterized by excessive vibration and an irregular engine noise. Shallow scoring on the piston and cylinder along the entire lateral surface height. The piston ring may be destroyed.
Lack of lubrication results in transfer of metal from the piston to the cylinder walls and engine seizure.
Excessive amount of oil in the fuel mixture leads to coking of the piston ring and formation of intensive soot on the piston.
Continuous use of the engine with the carburettor choke closed for extended periods of time may also result in heavy soot deposits on the pistons.
Also an indication of an engine running with too much oil in the fuel mixture is the presence of carbon deposits on the spark plugs and heavy coking of the muffler screen, which manifests itself in a loss of engine power when running.
Let’s look at some of the signs that tell you that the user is not following the Operator’s Manual recommendations regarding improper fuel use and lawn mower storage.
If dirty gasoline is used to make the fuel mixture, dirty deposits will be present in the carburetor.
Also a sign of dirty fuel will be a dirty fuel filter, located in the gas tank.
Oxidation of the carburetor components is an indication that the lawnmower has been stored with fuel for a long time. This changes the elastic properties of the rubber diaphragm of the fuel adjustment system and the diaphragm of the gasoline pump. There may also be tar deposits on carburetor components.
Gasoline tool manufacturers recommend adhering to the following proportions when preparing the fuel mixture:
Use oil that is labeled “For the gardening equipment. Do not use oil for boat engines, motorcycles, etc.д.
Use clean, fresh, unleaded gasoline with an octane rating of 92 or higher to prepare the fuel mixture.
Do not mix gasoline and oil together unless specifically instructed to do so. Use a special container to mix gasoline and oil. Do not mix gasoline and oil directly into the fuel tank.
Do not use an old fuel mixture that has been stored for more than 30 days.
Before storing for an extended time:. Remove fuel from fuel tank;. Run engine until all fuel is gone;. Remove spark plug, pour 30 ml of high-quality 2-stroke or 4-stroke oil into cylinder; pull starter handle to evenly distribute oil inside engine, and replace spark plug.To reduce the risk of injury, always wear safety glasses or goggles when operating the machine.
Proportion of gasoline and oil
The engine doesn’t need much oil to work properly. Its amount is always determined as a percentage, because the gas tank of saws can be of different capacity. Also, many operators prepare the mixture with a small margin, especially if serious work is to be done. After all, one tank of modern tools, for all their economy, is rarely enough for more than 1 cubic meter of firewood.
This is the standard due to the high quality of modern engines. Characteristic of most modern saws made in Germany, Switzerland, USA, Japan, Italy. In a word, all saws made not more than 10 years ago by world famous brands. Husqvarna, STIHL, Oleo-Mac, Makita, ECHO and others. will require exactly this proportion.You can read about it in the instruction manual.
However, many purely Chinese-made saws are also influenced by improved machining and assembly techniques. For example, many domestic brands of saws, assembled in Celestial Empire, also run on 1:50 mix. For example, on recent Zubr models, the label with the ratio marking appeared as a cardboard flag right on the handle of the starter cord, apparently for those who don’t like to look in the manual.
This ratio is often referred to as the “running-in ratio.”. This means that after you buy a new saw, you’ll need to pour a more oil-rich mixture into the gas tank. At this time, the moving parts of the cylinder-piston group are lapped, and a higher ratio is required than usual in the process. After burning a couple or three cans in a gentle mode, you can switch to the manufacturer’s recommended ratio.
Also 1/40 ratio is common in some manufacturers, such as in Partner chainsaws. Given that there is a little more oil than in the previous variant, a small excess will not harm any engine. With the use of high-quality fuel and lubricants there is another issue. the price of fairly expensive consumables.
Today is considered outdated. Widely used in domestic chainsaws of old design like Druzhba or Ural. Today it is still found in some Chinese chain saws of “nooname” class or branded by retail chainsaw chains. But every year the number of such products is decreasing and makes the most budget and low-quality niche of gasoline-tools. Besides, for such machines it doesn’t really matter how expensive and quality oil is in the gas tank. the engine life is not that long anyway.
Gasoline and oil ratio
The engine does not need much oil to work properly. Its amount is always determined by a percentage, because the gas tank of saws can have different capacities. In addition, many operators prepare the mixture with a small margin, especially if serious work is to be done. One tank of modern tools, for all its economy, is rarely enough for more than 1 cubic meter of firewood.
This is the standard due to the high quality manufacturing of modern engines. It is typical for the majority of modern saws of German, Swiss, American, Japanese, Italian manufacture. In a word, all saws, produced not more than 10 years ago by world famous brands. Husqvarna, STIHL, Oleo-Mac, Makita, ECHO and others. will require exactly this proportion.You can read about it in the instruction manual.
But many saws of purely Chinese manufacture are also influenced by improved technologies of processing and assembling. So, many domestic brands of saws assembled in the Celestial Empire, also run on the 1:50 mix. For example, on recent models Zubr a label with the marking of the proportion appeared in the form of a cardboard flag right on the handle of the starter cord, apparently for those who do not like to look in the instructions.
This ratio is often called “running-in”. This means that after buying a new saw you have to fill the fuel tank with a more enriched oil mixture. During this time, the moving parts of the cylinder-piston group are lapped, in a process that requires a higher ratio than normal. After burning a couple or three cans sparingly, you can switch to the manufacturer’s recommended ratio.
Also, the 1/40 ratio is common with some manufacturers, such as Partner chain saws. Considering that there’s a little more oil than the previous option, a little over-ratio won’t hurt any engine. When using quality fuel and lubricant is another issue. the price of fairly expensive consumables.
Today it is considered outdated. Widely used in older designs of Russian chainsaws, like Druzhba and Ural. Today it can still be found in some Chinese chainsaws of the “noname” class or branded by retail chains. However, every year the number of such products decreases and makes up the most budget and low-quality niche of gasoline tools. In addition, for such products it is not important how expensive and high-quality oil is poured into the gas tank. the engine life is still unscrupulously small in any circumstances.
Oil to gasoline ratio for a fuel mixture
The oil to gasoline ratio for a chainsaw is usually made in two prescriptions:
If the chainsaw is recently purchased and has not yet been operated, the proportion of lubricant is increased by a quarter. The same amount is put into fuel when sawing at temperatures below 2 degrees Celsius.
Getting such a mixture is not particularly difficult. Almost every modern saw is equipped with special two-section fuel tank. The smaller part holds oil and the larger part holds gasoline. Screw the lids on both parts on tightly and turn the container upside down and shake it thoroughly. This ensures that both components are completely and homogeneously mixed.
If there is no such special container, you can use any gasoline-resistant plastic container with a one-liter lid and a disposable syringe for 5-10 cc. The container for the petrol must be cleaned of any dirt and water beforehand. After that, one liter of 92-95 gasoline is poured into it.
At the same time 20 ml of oil are added to the syringe. If the filling is made in cold time, it should be taken 24-30 ml. Carefully pour it into a container with petrol. It is tightly closed with a lid and shaken thoroughly until the components are fully mixed.
Oil to gasoline ratio for a chainsaw
Each chainsaw company adjusts the engines and base carburetors to work with different amounts of lubricant. That is why the oil and petrol proportions for the chain saw may be slightly different.
Most often, when mixing fuel with oil, manufacturers advise using a 1:50, or 1:40 ratio. It means that 1 part of the engine lubricant should be mixed in 50 or 40 parts of fuel, respectively.
To translate the proportion in a more accessible wording is quite simple. For example, 1 liter of fuel contains 1000 ml. If 1000 ml divided by 40, you get 25 ml. This means that for 1 liter of gasoline you need to dilute 25 ml of lubricant. The same formula should be used when the manufacturer recommends preparing fuel mixture exclusively in the proportion of 1:50. To do this, divide 1000 ml by 50, which results in 20 ml. This means you should dilute 20 ml of motor oil in 1 liter of fuel.
Slightly different for Chinese chain saws. Their manufacturers recommend diluting gasoline for chain saws at a ratio of 1:25. This means that owners of Chinese tools need to stir exactly 40 ml of lubricant in 1 liter of pure gasoline. This ratio is due to the fact that the quality of assembly and the selection of components, these chainsaws are slightly inferior to their Western counterparts. The engines of American, European and Japanese models have a much smaller distance between the cylinder and piston than chainsaws from China. Because of this, the amount of lubricant required to operate the former. much less.
How to dilute gasoline for a chainsaw?
The mixture of oil and gasoline for a chainsaw must be made with quality components. The best solution is gasoline with an octane number of AI-92 and engine oil from proven manufacturers.
The proportion of oil and gasoline for a chainsaw can be different. it all depends on the power and the instructions of the tool manufacturer. If you don’t know how much oil to put in your gasoline for your chainsaw, first of all, read the recommendations in the instruction manual carefully. In the vast majority of cases, about 20-50 ml of engine oil per 1 liter of gasoline is required.
In practice, for two-stroke chainsaw engines of no more than 1.5 kW you need about 25 ml of engine oil. For more powerful garden tools about 30 ml should be used.
How to prepare the fuel mix: Proportion of oil and gasoline for the chain saw
The chainsaw engine is the “heart” of the machine, and it is very important to use a proper fuel mixture.
The fuel mix for a chainsaw is made of two components. oil and gasoline. Chainsaws are fitted with two-stroke engines, so oil is not added to the lubrication system (as with a four-stroke engine) but directly to the petrol. It is very important to observe correct proportions of ingredients and of course not to try to work with pure gasoline, because that will “kill” the chain saw very quickly.
Always use oil suitable for the two-stroke engines of forestry equipment (i.e. never use oil for outboard motors or scooters). As practice shows, you can buy this oil in any store or service center, where chainsaws are on sale or made by their service.
If we talk about what gasoline pour into the gasoline chainsaw, it will be optimal to use fuel with an octane number of A-95, in this case, the savings on fuel can turn out badly. Often, European manufacturers specify that it is possible to use gasoline A-90 or A-92, but in post-Soviet countries the quality of gasoline is inferior to European, so in our realities it’s better to use high-quality gasoline.
As for the proportion of gasoline-oil mixture itself, everything is simple: you must clearly follow the instructions of the tool. All chainsaw manufacturers indicate the necessary ratio in the instruction manual or in the passport of the tool, besides, the proportions for filling the chainsaw may differ depending on the model of the chainsaw. As a rule, the ratio of oil and gasoline to a chainsaw from reputable manufacturers is 1:40 or 1:50, which means 1 part oil to, say, 40 parts gasoline.
Now the arithmetic. 1 liter of gasoline = 1000 ml of gasoline, divided by 40, we get 25 ml of oil. If you do the same for a 1:50 ratio, you get 20 ml of oil per 1 liter of gasoline.
With cheap Chinese-made chainsaws, the situation is slightly different. Gasoline to oil ratio for chainsaws made in China 1:25, that is 1000 ml of petrol divided by 25, you get 40 ml of oil. The thing is that in branded chainsaws solid build and the distance between the pistons and cylinders in the engine is much smaller than in Chinese saws, so the required amount of oil is different and almost twice as much.
to measure out the right portion of oil, use an ordinary medical syringe of sufficient volume.
One more tricky part. In a dry gasoline canister, first pour the gasoline, then the oil. The procedure on the contrary is fraught with a fuel mixture of poor quality, because the oil is more dense, will stick to the bottom of the canister. That’s why there is no way to mix it well.
The fuel tanks of chain saws have capacities of 0.3 to 1.0 l. Always prepare fuel mixture in the fuel canister and fill the tank with ready-to-use fuel! Never prepare and mix it directly in the fuel tank of your chainsaw!
If the question of how to dilute gasoline for a gasoline-powered saw is solved, then the on fuel mixture storage conditions and expiration dates it is worth saying a few words. It is best and easiest to prepare gasoline-oil mixture for 1 liter of gasoline, it is recommended to do it just before working with the tool. The fuel tanks of chainsaws have a volume of 0.3 to 1 liter. In conditions of domestic use for one session is rarely used the entire volume of the prepared combustible mixture, so the remainder can be saved until the next session of work. The fuel mixture should be stored in a special gasoline canister, in a dry, dark place. It is optimal to count on The storage time of the ready mixture is 7-10 days
The fact is that the oil currently on the market is not synthetic, but organic, that is natural. After 10 days all lubrication properties are lost, gasoline simply “eats” the oil. Of course, you can not use such a fuel, it can cause damage and failure of the chainsaw.
At the end of the work it is necessary to drain the fuel mixture and start the chainsaw. the tool will stall (so that the saw has a dry carburetor) and now you can leave it until the next session of operation.
Choice of chain oil
In addition to the motor, for which we have already figured out all the proportions of oil and gasoline for STIHL chain saw, there is another important part, consisting of many moving parts. the chain. To lubricate it, they don’t use motor oil, but chain oil. It has totally different properties and costs less.
For a new instrument, use only the oils of the manufacturer that are recommended in the instructions. Otherwise, if the saw breaks down, it will be removed from the warranty due to non-compliance with operating conditions. It should be noted that the oils from the manufacturer are of really high quality. After the end of the warranty period, you can use any engine oil, changing it twice a year.