Fuel Trim Ratio

The choice of oil and gasoline for preparing a fuel mixture for a trimmer: a table of the ratio of dilution What oil and gasoline to choose for refueling a garden trimmer. The proportions of the preparation of the fuel mixture for two-stroke engines of gasoline-powered tools. How to properly and safely refuel lawn mowers. Lawnmower Tips to Help Extend Tool Life in Your Home

Which oil to choose

For effective trimmer operation, it is necessary to select oil for two-stroke engines. This is due to the lack of an oil sump in such a device. Depending on the chemical composition of the oil, the following classification is distinguished:

  • Mineral. Based on petroleum distillate, suitable for low-power equipment and with an air type of cooling, but requires frequent replacement and can only be used in good weather during the warm season;
  • Semi-synthetic. Suitable for garden equipment with air and liquid cooling;
  • Synthetic. They are based on esters, do not require frequent replacement and can be used at any time of the year.

Oil for 2-stroke engines is characterized by good solubility and complete combustion feature. It is recommended to use a lubricant for the trimmer that is suitable for air-cooled units. Most often, it is indicated on the packaging that the oil is intended for gardening equipment and is marked TA, TB or TC. And the last one is the most preferable.

If the consumption of engine oil during the summer season is planned to be large due to the presence of a chainsaw, brush cutter, lawn mower in the garden arsenal, then it is advisable to buy 5 liters of oil at a more favorable price. If it is needed only to mix with gasoline and fill the only tool, then 1 liter will be enough.

Lawn mower manufacturers often produce the right oil, so you can make your choice easier if you choose the right brand of fluid.

The choice of oil and gasoline for preparing a fuel mixture for a trimmer: dilution ratio table

A trimmer, or lawn mower, is an indispensable tool in the household. Over, its reliability, efficiency and long service life depend on many factors. For example, the quality of fuel. This means that you need to select the right trimmer oil, observe the proportions when added to gasoline and the rules for refueling the device.

fuel trim ratio

What gasoline to fill

Gasoline for the trimmer should be chosen unleaded with a stroke number of 92 or 95. As practice shows, AI-80 gasoline can damage the device, which is a questionable economy.

Fuel must be fresh, that is, after purchase, it can be stored for no more than 60 days.

Other factors also affect the quality of the fuel, such as using a special lawn mower lubricant and diluting it in a separate container. It is also recommended to use special canisters designed for storing gasoline.

How to breed

Stihl saw fuel mixture is prepared by mixing high-octane gasoline and two-stroke engine oil. The proportion of oil and gasoline for a chainsaw is as follows: if the power of the unit does not exceed 1.5 kW, then the ratio will be 1:40 (that is, 25 ml of oil per liter of gasoline), and with a power higher than this value. 1:50 (20 ml 1 liter).

Looking at the table of proportions, we will analyze, using the example of two saws of different power, how to mix oil gasoline.

  1. For the low-power STIHL MS 180 with a 2-stroke engine, the dilution will be 1:40. The volume of the fuel tank is only 0.25 liters. In order to mix fuel and oil for one filling, we need 6.25 ml of oil for 0.25 liters of gasoline.
  2. For the STIHL MS 660 heavy-duty professional chainsaw, dilute oil and gasoline in a ratio of 1:50. This model has a fuel tank capacity of 0.825 l. In order to understand how much oil to pour for such a volume of gasoline, multiply 0.825 by 20. It turns out that 16.5 ml of engine oil is required.

In practice, of course, it is not necessary to calculate how much of the lubricant will be diluted in the volume of gasoline per filling. Usually, the fuel mixture is diluted in a volume of 1-2 liters, which is enough for several refueling of the chain saw.

You need to dilute gasoline for the Stihl chainsaw in a separate canister, in no case pouring the components into the saw’s gas tank separately. These engines do not have an oil pump and the possibility of installing it, so only ready-made fuel is poured into the tank. There are even special canisters with two necks on sale to make it easier to dilute the mixture, but you can add oil to gasoline for a chainsaw and in an ordinary canister.

It is better to observe the proportions of refueling the chainsaw as accurately as possible: excess oil will create carbon deposits on the spark plugs and pistons and provoke detonation during fuel combustion. This can shorten the engine life. In addition, the user of the saw in this case is forced to inhale the exhaust gases with unburned fractions. At the same time, excess gasoline can damage pistons due to insufficient lubrication.

Some craftsmen, in the absence of special measuring accessories, advise using a plastic bottle: a full cap (from the same bottle) of oil is poured into a half-liter container filled with gasoline. The output is approximately 1:50.

It is better to calculate the amount of mixture for refueling in advance based on the expected amount of work and the declared consumption of this engine. The volume of the tank in most chainsaws is about 0.5 liters, a 2 kW engine will consume approximately 1.2 liters per hour of operation (for more precise characteristics of the saw, see the instructions). Thus, it makes no sense to prepare a mixture in quantities exceeding 3 fillings in a row.

Before starting the preparation of the mixture, it is recommended to thoroughly clean and dry the neck of the canister and the area around it in order to avoid the ingress of impurities: dust, water, etc. The same is done with the tank before filling the fuel: the lid and neck are cleaned of dust and adhering dirt, so that it does not get into the gas tank, and then into the engine.

Ratios of gasoline and oil for the Stihl trimmer

The German manufacturer of high-quality cutting tools Stihl also produces motorized mowers in addition to chainsaws. It is an indispensable tool for mowing grass and lawn trimming, lightweight and mobile.

A lawn mower, or trimmer, also has a two-stroke engine and is fueled with a fuel mixture. For the Stihl trimmer, a ratio of 1:50 is recommended (for 5 liters of gasoline, 100 ml of oil).

What gasoline and oil is best for refueling a Stihl chainsaw: a table of ratios, how to breed, proportions

The durability and reliability of a chainsaw is determined not only by the conditions of its operation, but also by the quality of the fuel used for refueling. In addition to the special conditions of use when lapping parts in the first few refuelings, attention must also be paid to the quality of the fuel mixture.

Professional Stihl chainsaws are equipped with two-stroke engines that require high-quality fuel. A metered mixture of high-octane gasoline and oil, designed to operate the engine at high speeds. The correct choice of gasoline and oil for the Stihl chainsaw is the key to a long and successful operation of this unit.

Types of engine oils and their purpose

The choice of oil for the petrol trimmer

Gasoline trimmer engine oil is a lubricant that is used to reduce wear between the rubbing engine components.

The oil composition includes residual hydrocarbons and various additives that improve the properties of the final product. To ensure long-term and trouble-free operation of lawn mowers, experts recommend using oils that correspond in their physical and chemical properties to this type of motor.

Today it is customary to distinguish between three main types of oils according to the way they are obtained:

  • Mineral, created in the process of distillation of hydrocarbons;
  • Synthetic oils obtained by natural gas processing or synthesis;
  • Semi-synthetic, containing improved mineral oil with the addition of some synthetic components.

In order to prevent mixing of various types, the manufacturer adds a dye to the oils, which indicates the difference in the composition of the lubricant.

Choosing a lawn mower oil

For trimmer engines it is necessary to choose oils marked “2T”, which are used for internal combustion engines with a volume of 50 to 200 cm 3 and are air-cooled. First of all, when buying oil, you should pay attention not to the price, but to the protective properties of the material, since small savings can subsequently become a real headache for the owner and, as a rule, high costs.

Two-stroke lawn mower oil

The main factor in determining the quality of trimmer oil is the base number. It is this component that excludes oxidation of rubbing parts and slows down their destruction. During operation, the oil gradually loses its alkalinity and becomes oxidized. The optimum acidity level (Ph) should not be less than 8-9 units.

The viscosity of lawn mower oil also has a big impact on how a gasoline tool works. This indicator determines the ability to operate the trimmer at different temperatures. For example, summer brands of lubricants thicken even with a slight decrease in temperature. Due to the use of lawn mowers exclusively in the spring and autumn period, oil with summer marking would be an excellent option.

The flash point for trimmer oil should be more than 225C, otherwise the oil will burn out quickly and the piston group will be subject to intense wear.

What to look for when choosing an oil?

Modern two-stroke engines of the lawn mower are fueled with a mixture of AI-92 gasoline and oil marked “2T”. Using a fuel with a higher octane rating will increase the flash point and therefore burn out the lubricant.

Stihl oils

Undoubtedly, the best trimmer oil is the one recommended by the manufacturer, but the owner does not always have the opportunity to purchase exactly the “branded” lubricant. Experts recommend Shell Helix Ultra, based on Pureplus technology, which improves the basic properties of the lubricant.

For gasoline trimmers of the German manufacturer Stihl, it is necessary to use oils Stihl HP Ultra, Stihl HP, Stihl HP S. A budget substitute can be the products of the Vityaz company, which in their properties are most similar to the recommended material.

Fuel mixture: the proportion of oil and gasoline for the chainsaw

The chainsaw engine is the heart of the tool, so it is very important to use a properly prepared fuel mixture.

Chainsaw fuel mixture prepared from two components. Oil and gasoline. Chainsaws are equipped with two-stroke engines, so oil is not added to the lubrication system (like a four-stroke engine), but directly to gasoline. In this case, it is very important to observe the correct proportions of ingredients, of course, in no case try to work on pure gasoline, because in this way you will very quickly “kill” the chain saw.

If we talk about what kind of gasoline to pour into the chainsaw, then it will be optimal to use fuel with an octane number A-95, in this case, fuel savings can turn out to be deplorable. Often European manufacturers indicate that it is possible to use A-90 or A-92 gasoline, but in post-Soviet countries the quality of gasoline is inferior to that of Europe, so in our realities it is better to use higher quality gasoline.

As for the proportions of petrol-oil mixture, then everything is simple: you need to follow the instructions for the tool. All manufacturers of chainsaws indicate the required ratio in the instruction manual or in the passport of the tool, in addition, the proportions for refueling the chainsaw may differ depending on the model of the chain saw. As a rule, the proportion of oil and gasoline to a chainsaw of famous manufacturers is a ratio of 1:40 or 1:50, which means 1 part of oil for, for example, 40 parts of gasoline. Now arithmetic 1 liter of gasoline = 1000 ml of gasoline, divide by 40 and we get 25ml of oil. If you follow the same steps for the ratio 1:50, then we get 20 ml of oil per 1 liter of gasoline. As for budget chainsaws made in China, the situation is slightly different. The ratio of gasoline to chainsaw oil made in China 1:25, that is, divide 1000 ml of gasoline by 25, we get 40 ml of oil. The thing is that in branded chainsaws, a solid assembly and the distance between pistons and cylinders in the engine is much less than that of Chinese chainsaws, therefore, the required amount of oil differs almost twice.

Use a conventional medical syringe with sufficient volume to measure the correct amount of oil.

Another subtlety. First fill the dry gasoline can with gasoline and then oil. The procedure, on the contrary, is fraught with a low quality fuel mixture, because the oil is more dense, it will stick to the bottom of the canister. What a good mixing there is.

Be sure to prepare the fuel mixture in a canister and pour ready-made special fuel into the gas tank! Never cook or mix it directly in the fuel tank of your chainsaw!

If you figured out the question of how to breed gasoline for a chainsaw, then storage conditions and shelf life of the fuel mixture it is worth saying a few words. It is best and easiest to prepare a petrol-oil mixture for 1 liter of gasoline, it is recommended to do this immediately before working with the tool. Chainsaw fuel tanks have a volume of 0.3 to 1 liter. In the conditions of domestic use, the entire volume of the prepared combustible mixture is rarely used in one session, so the remainder can be saved until the next session. It is necessary to store the fuel mixture in a special canister for gasoline, in a dry, dark place. It is optimal to count that shelf life of the finished mixture will be 7-10 days. The fact is that the oil on the market now is not synthetic, but organic, that is, natural. After 10 days, all lubricating properties are lost, gasoline simply “eats” the oil. Naturally, it is no longer possible to use such fuel, this can cause breakdown and failure of the chainsaw.

At the end of the work, it is necessary to drain the fuel mixture, start the chainsaw, the tool will stall (so that the saw has a dry carburetor) and now you can leave it until the next operation.

Dispose of unsuitable fuel mixture.

Mixing rules

And now about how to mix the components correctly. However, it would be more logical to start with an analysis of common, but absolutely unacceptable mistakes that many owners of this mowing unit “sin” with. The following actions are considered as mixing errors.

  • Adding oil to the fuel already poured into the mowers’ gas tank. In this way, a homogeneous fuel mixture cannot be obtained. Perhaps it will work, if only then shake the trimmer for a long time. But it is unlikely that someone will do this, given the severity of the unit.
  • First pour oil into a mixing container, and then add gasoline to it. Gasoline has a lower density than oil, so if it is poured into oil, it will remain in the upper layer, that is, natural mixing will not occur. Of course, it will be possible to mix later, but much more energy will be required than if it were done the other way around. Pour oil into the poured gasoline.
  • Ignoring precise measuring instruments for taking the required quantities of ingredients used. In other words, diluting the amount of oil or gasoline “by eye” is a bad habit when operating motor vehicles.
  • Take empty drinking water bottles for preparation of the fuel mixture. Such containers are made of too thin polyethylene, which can dissolve with gasoline.

Considering all of the above, we recommend using the following rules when mixing a fuel mixture for two-stroke trimmer engines.

  1. Use only clean containers made of metal or special plastic for storing gasoline, oil, ready-made fuel mixture and its preparation.
  2. Use a watering can for filling gasoline into the dilution container to avoid spilling, and for adding oil. In a measuring container with volume risks or a medical syringe for 5 and 10 ml.
  3. First, pour gasoline into the canister for preparing the fuel mixture, and then oil.
  4. To dilute the mixture, first pour only half of the planned volume of gasoline into the container.
  5. Next, add to the gasoline the entire amount of oil required to prepare the mixture.
  6. Mix the contents of the dilution container thoroughly. It is best to stir by making circular movements with a tightly closed container. You should not stir the fuel inside the canister with any foreign object, since it is not known what material this object is made of, what reaction it can enter with the ingredients of the mixture, how clean it is.
  7. Add the rest of the gasoline to the mixed mixture and mix thoroughly again.
  8. You can fill the mowers’ fuel tank with the prepared mixture.

It should be borne in mind that the ready-made fuel mixture should not be stored for more than 14 days, as it loses its properties, stratifies and evaporates, which leads to changes in proportions, and hence a deterioration in trimmer performance.

Gasoline to Lawn Mower Oil Ratio

  1. Standard proportions
  2. Mixing rules
  3. Consequences of violation of the ratio
  4. How to choose a lawn mower?

Lawn mowers are a fairly common technique for combating weeds in summer cottages, in household, road and housing and communal services. These devices have two more names. Trimmer and lawn mower. These units differ in their engines. The more expensive ones have four-stroke engines, all the others have two-stroke engines. Of course, the latter are the most popular among the population, since they are simpler in design, and lighter in weight, and much cheaper than their four-stroke competitors. However, two-stroke models are inconvenient in that the fuel mixture for them must be prepared by hand, maintaining a strict dosage between gasoline and oil. In four-stroke analogs, the mixing of these components occurs automatically, you only need to fill the gas tank and oil tank with the corresponding substances. Let’s consider the question of the correctness of refueling precisely two-stroke lawn mowers, since it depends on how effective and long the operation of such a unit will be.

Standard proportions

First of all, it is necessary to take into account the information that the manufacturer recommends, since in the event of a failure of the lawn mowers, you can present your claims to him, and not to a third-party source. If there is no instruction in the passport, and even more so if there is no passport, then we recommend looking for another trimmer model from a more reliable seller.

For all other cases, when you have a lawn mower model in your hands and there is no way to find out its technical features, there are standard proportions of the most likely fuel mixture components for a two-stroke engine. Basically, these units use AI-92 gasoline and a special synthetic oil, which contains a solvent for better mixing with fuel. Such oil evaporates slowly and has the ability to completely burn out in the cylinder, leaving no carbon deposits.

The standard ratio of synthetic oil to gasoline is 1: 50. This means that 5 liters of gasoline need 100 ml of oil, and in accordance with this oil consumption per 1 liter of gasoline is 20 ml. Knowing the amount of oil required to dilute 1 liter of fuel, you can easily calculate any rates when preparing fuel for the trimmer. When using mineral oils, the ratio of 1: 40 is most often standard. Therefore, 1 liter of fuel will require 25 ml of such oil, and for a 5 liter canister. 125 ml.

When working with lawn mowers, a person with little experience in operating such equipment will not be difficult to determine and correct the actual amount of oil required for a particular model. You should only pay attention to the exhaust gases (their color, odor toxicity), cycle stability, engine heating and developed power. Details about the consequences of incorrect mixing proportions of gasoline and oil can be expected in another section of the article. There are variants of lawn mowers running on AI-95 gasoline. This should also be considered.