How to prepare fuel for a grass trimmer

How much oil to put in a grass trimmer per liter of gasoline

Gasoline mowers are fairly common tools used by garden and homestead owners for mowing grass and making hay. common names for tools are the terms “grass trimmer” and “lawnmower”. The main difference is hidden in the design of the motor. the expensive segment of the devices is equipped with four-stroke models, and the cheap ones. two-stroke. The latter option has advantages, including low weight, ease of use, as well as low cost.

The most important condition for the work of two-stroke models is the preparation of the fuel mixture, based on the manufacturer’s defined proportion of gasoline and oil. The simplified design of the motor does not provide a separate channel for lubrication, so engine oil is added directly to the gasoline. Violation of the correct proportion leads to a significant reduction in the resource of the tool and even to its failure. Let’s understand what composition is required for gasoline trimmers, how to properly prepare the mixture and what it can affect.

The choice of gasoline for grass trimmer

For some reason, everyone prefers to choose a brand of gasoline for brushcutter at its discretion. This is an erroneous approach, because, first of all, you should carefully study the instructions, where the manufacturer’s recommendations on the choice of fuel type are given. But this is also not a guarantee, as unleaded fuel can be sold under different brands (which differ in many manufacturers), with significantly different composition. Therefore, it is necessary to be guided by the main characteristics to choose the gasoline for a particular model of trimmer for grass.

Manufacturers of gasoline tool manufacturers recommend using gasoline brand AI-92, but for more expensive types will need fuel with a higher octane number. AI-95. Any brand that has the number 90 or less in its label is not suitable for benzocos as it leads to quick wear and tear. The problem is due to unscrupulous fuel producers who sell a completely different brand under the guise of 92. The situation is as follows:

  • In the passport of gasoline equipment there is a recommendation to use gasoline with an octane number not lower than 92;
  • The conscientious owner goes to the gas station, where the lowest price and with a clear conscience pours such fuel into the brushcutter;
  • As a result, the service life is reduced, because often under the guise of AI-92 sold AI-80 and AI-76.

Filling up with fuel

To avoid such situation, you should choose a filling station which sells reliable gasoline (it can be defined by the recollections of regular customers). It is important where to fill the fuel after purchase. only metal containers should be used for this (plastic is prohibited).

Preferably, when it is possible to buy gasoline for high-clearance grass trimmer specifically for garden equipment. Then you can be sure of its quality and protection against counterfeiting.

How to mix (dilute) gasoline and oil for 2T engines.

To summarize. Use for your brand name equipment the oil developed or recommended by the equipment manufacturer. For example, STIHL FS 55 brushcutter with STIHL HP oil (see the STIHL manual for STIHL trimmers). Figure 1a) or STIHL HP SUPER, for the Husqvarna 128R brushcutter use Husqvarna HP oil (Figure 1b) or Husqvarna LS. For 2.Do not use engine oils for 4-stroke engines. for example 10W30, SAE 30, etc.д.

Figure 1 a-Husqvarna oil (left), STIHL oil (right)

Useful tip

Never use 2-stroke oil intended for water-cooled engines, because these oils are designed to operate at lower temperatures.

You should follow the proportions of oil and gasoline for the fuel mixture that are specified by the manufacturers in the owner’s manual. Chinese manufacturers most often indicate the ratio of 1 part oil to 25 parts gasoline, with STIHL and Husqvarna this proportion is 1 / 50.When preparing a small volume of mixture (up to 1 liter), it is very important to carefully measure the oil in the mixture. Even small miscalculations in the amount of oil can lead to serious inconsistencies in the mixture. In these cases, a medical syringe can be used for precise dosing.The fuel mixture must be prepared in a clean container especially designed for this purpose. (see pic. figure 2)

Useful hint

I do not recommend the use of improvised plastic bottles and canisters, as gasoline can dissolve plastics and all this “slurry” gets into the fuel tank and disables the carburetor.

Plastic canisters designed for gasoline are always marked with a “flame” sign. It is very convenient to use a canister with a no-fill system (see Figure 3). Figure 3). The no-flooding system has a valve that prevents fuel from spilling when the tank is full.

Figure 3. No Spill System

What is the best oil for your outboard?

Also note that if these oils cannot be used to make gasoline mixture for boat engines. In 2T boat motors it is necessary to fill in a mix prepared from gasoline with octane number not lower than 89 and ultrapure oil with detergent additives of NMMATC-W3 marking in the proportion 1:50 for operation mode, and. 1:25 for break-in period (first 5 to 10 hours). Selection of quality oil.The basis of the engine, so each manufacturer recommends pouring into the technique of a certain brand of oil, thereby guaranteeing the longest life of the product. For Honda boat motors (both 2t and 4t) tohatus service center recommends to use german motul or american quicksilver oils. For mercury outboard engines it is necessary to use only quicksilver motor oil. The preferred brands for Honda boat engines are motul and statoil.

Useful hint

It is not recommended to use the fuel mixture if more than 2 months have passed since its preparation.

What is the best oil to choose for boat motors.

Also note that if these oils can not be used for the preparation of gasoline mixture for boat motors. 2T boat engines shall be filled with petrol mix of at least 89 octane number with high-purity detergent oil grade NMMATC-W3 in proportion of 1:50 for each operating mode, and. 1:25 for break-in period (first 5-10 hours). Choosing the right the basis for the engine, and each manufacturer recommends that you fill your machine with a certain oil grade to ensure the longest possible working life of the product. So for the boat motors (both 2t and 4t) tohatus service center recommends to use german motul or american quicksilver oils. For mercury boat motors you must use only quicksilver motor oil. For Honda powerboats the preferred brands are motul and statoil.

Useful tip

It is not recommended to use the fuel mixture if more than two months have elapsed since preparation.

Choice of oil

The first document to refer to when selecting an oil brand is the tool data sheet. The manufacturer not only specifies the characteristics of the lubricant there, but also offers specific brands and trade names.

If it is not possible to refer to the manual, it is recommended to use only two lubricant options:

  • Semi-synthetic motor oils, which are of medium value (slightly higher than mineral oils). Produced by distillation of high-molecular oil products, produce little smoke and have good engine component protection. Can be used in both domestic and foreign trimmers;
  • Synthetic motor oils, which usually have the highest value in the range. This is the most reliable wear protection for the motor, compatible with any power unit.

In addition to the basic type of oil, it will also be useful to read its letter marking in order to choose a compatible type according to parameters. According to the European API classification there are the following designations for two-stroke engines:

  • TA. oil for small volume power units (not more than 50 cu.m.). see.), which makes it possible to recommend this particular type for motor vehicles;
  • TV. Grease for larger engines with displacement between 50 and 200cc. see. It is allowed to use such for a brushcutter;
  • TC is an engine oil for serious equipment (motorcycles, snowmobiles, scooters), assuming mixing with gasoline;
  • TD. lubricant for flooding vehicles.

There is also a classification of the Japanese organization JASO, which in assigning labels focused on the level of smoke. It is necessary to decipher these designations:

  • FA. during combustion, smoke emission is negligible and barely visible to the naked eye. For countries with strict emission requirements;
  • FB. a little more visible smoke of white color, but more than the FA;
  • FC. transparent smoke, which is not visible at a glance;
  • FD. smokeless oils used for filling watercraft.

You can also see the “Self MIX” and “Pre MIX” designations on the canisters. The first option means that once added to the fuel, the mixture does not need to be forcibly stirred. The second option. the gasoline-oil mixture must necessarily be mixed by hand.

Using these three marking options, it’s easy enough to choose the type and brand of lubricant you need. The only question is the rating of manufacturers. Here are the most famous brands that produce only high-quality fuel and lubricants:

  • SHTIL. a popular manufacturer of gasoline equipment and consumable components for them;
  • Shell Helix Ultra. used for both cars and small motor vehicles;
  • Motul. generally acknowledged leader in the production of lubricants;
  • Lukoil is a domestically produced brand that is not inferior in quality to its foreign counterparts.

It is recommended not to save on engine oil, because the trouble-free operation of the power unit depends on it.

Varieties of motor oils, their purpose

Motor oil is a special composition of a solvent and additives that reduce friction, create a proper fluidity and prevent thickening at lower temperatures.

  • mineral, acquired by distillation of crude oil;
  • synthetic. by synthesis or processing of natural gas
  • semi-synthetic. improved mineral oil by adding synthetic components.

For safety reasons, the oil is colored red, blue or green so as not to confuse the products. The range varies in composition, the user should buy an oil marked “for garden equipment” 2T if you want to prepare a mixture for the two-stroke engine

Synthetic and mineral oils have different bases and must not be combined. When changing to another type of oil the system should be thoroughly cleaned.

for a lawnmower should refer to the systematization of TC oils created for air-cooled engines with a combustion chamber volume of 50-200 cm3 When choosing a product, the fundamental parameter is not the cost but the protective characteristics for a particular brand of engine. Therefore, first buy the recommended oil, if not, pick up similar indicators.

Defines the quality of lawnmower oil alkali number. Alkali neutralizes oxidation of friction materials, slows down deterioration of surfaces. When oil becomes oxidised, it loses its protective properties. Typical oil pH is 8-9.

Viscosity is important. That’s why there are winter, summer and multigrade oils. Which oil to use

For the lawnmower, it depends on whether the user will operate at sub-zero temperatures. Summer oils thicken even when it gets a little cold. Flash point shows how fast the oil will burn out. The fuel for two-stroke engines and classification of oils. Practical hints on how to dilute petrol and grass trimmer oil. It is normal if this value is above 225 C.

Varieties of engine oils, their purpose

motor oil is a special composition, consisting of a solvent and additives which reduce friction, create a proper fluidity and prevent thickening at lower temperatures.

  • mineral oils, acquired by distillation of petroleum;
  • synthetic. by synthesis or processing of natural gas;
  • Semi-synthetic is an improvement of a mineral oil by adding synthetic components.

For safety reasons, the oil is colored red, blue or green so as not to confuse the products. The range varies in composition, the user should buy the oil marked “for garden equipment” 2T if it is necessary to prepare a mixture for a two-stroke engine

Synthetic and mineral oils have different bases and must not be combined. When changing to another type of oil the system should be thoroughly cleaned.

for lawnmowers should be classified as TC oils for air-cooled engines with a combustion chamber volume of 50-200 cm3 When choosing a product, the fundamental parameter is not the cost but the protective characteristics for an engine of a certain brand. That’s why you buy recommended oil first, and if it is unavailable, choose similar oil.

Lawnmower oil quality is determined by the alkali value. Alkali neutralises oxidation of wearing parts, slows down surface degradation. When oil becomes oxidized, it loses its protective characteristics. Normal oil pH is 8-9.

Viscosity is key. That’s why there are winter, summer and multigrade oils. Which oil to use

The oil used for the lawnmower depends on whether or not it can be used at sub-zero temperatures. Summer oils become thick even when it gets a little colder. Flash point indicates how quickly the oil will burn out of the composition. Special features of two-stroke engines and oil classification. Practical tips on how to dilute petrol with oil for grass trimmer. It is OK if it is over 225 C.

Standard proportions

It is defined by the standard that to prepare a petrol-oil mixture, you need to take technical liquids in the ratio of 1 to 50. This means that you need to add 200 milliliters of oil to 10 liters of gasoline. If you need to dilute the amount per liter of gasoline, then use the formula according to the proportion rule.

Note that when using mineral oil, the proportion is less and is 1 to 40 per liter of gasoline as standard.


Now we have to choose which gasoline to fill the trimmer for grass. There is not much choice. AI-92 and AI-95. The difference between the two is quite significant. If the manufacturer’s instructions do not specify what gasoline to use, you must stop at AI-92. It almost does not depend on the brand of gasoline, how much oil to add per liter of gasoline, if the fuel is of high quality and fully complies with the declared brand. Buy gasoline only at brand gas stations, where the risk of buying A-80 instead of AI-92 is practically zero.

If it is recommended to use AI-95, do not use other brands of gasoline. If the engine starts, it will work irregularly and overheat quickly. So you run the risk of damaging the motor not only the domestic trimmer for grass, but also the professional one.

Learn how to dilute gasoline and oil for a grass trimmer if you under or overfill the oil

If you have bought a trimmer for the grass, lawnmower, brush cutter, chainsaw and other types of equipment, you probably know that two-stroke motors are used as power units on them. These engines don’t run on pure gasoline like four-stroke engines, but on a mix of gasoline and oil. In what proportion should you dilute gasoline with oil for grass trimmer. this is the question every dacha owner asks himself before preparing the tool to work. In this issue, let’s understand in detail, because the dilution of gasoline with oil for grass trimmer affects the service life of the tool, and improper preparation of the mixture, will lead to rapid wear and tear of the engine. How dangerous is the excessive or insufficient amount of oil in gasoline for grass trimmer:

  • If gasoline will be diluted with a lot of oil (above the norm), it will lead not only to a large amount of smoke, but also to the formation of soot on the walls of the cylinder and a drop in power.This soot will cause the piston to wear out, which will be diagnosed by a decrease in its performance
  • If the gasoline does not contain a sufficient amount of oil poured into the grass trimmer, it is even more dangerous.In fact the working mechanisms of the engine will not be lubricated in a sufficient quantity, which will eventually lead to their rapid wear and tear (there is a rapid destruction of piston rings and engine seizure). If there is not enough oil in the gasoline poured into the grass trimmer, wear and tear on the motor will occur dozens of times faster

To avoid having to pay for mistakes at the cost of an engine overhaul or buying a new tool, you should fill the tank with fuel of the correct consistency from day one. You can check the ratio in the instruction to the tool, because different manufacturers’ models may give different recommendations. Usually this ratio is as follows:

  • 1 to 25, or 40 grams of two-stroke oil per one liter of gasoline
  • 1 to 40 or 25-30 grams of grease per 1 liter of gasoline
  • 1 to 50. that is, 20 grams of oil is added to a liter of gasoline

The standard ratio is 1:50 (it is specified on the canisters of oil for two-stroke engines), but you have to rely on it as a last resort, because the manufacturers indicate the recommended ratio, and if it is not observed, the service life of the two-stroke motor is reduced.

In addition to following the ratio, you must also learn how to prepare the mixture. In fact, the option of adding oil to the gas tank, is categorically contraindicated, although some do so. If you bought a grass trimmer or lawnmower, you will need the consumables you will use to prepare the mixture. The instructions for preparing the fuel mixture in the grass trimmer is as follows:

  • Prepare gasoline and two-stroke oil, based on the above recommendations on the choice of lubricant and fuel
  • In addition, for the preparation of the mixture you need to take a container or a container. Usually a plastic bottle is used for this purpose, which should be chosen accordingly. It must be clean inside. Using a container from milk beer and other drinks is not recommended. A mineral water bottle is best
  • It is very important that the container had a whole value of volume, that is 1 or 2 liters, so you don’t have to calculate how much to pour oil in a bottle of 1.5, 1.3 or 1.25 liter, because you can easily go wrong
  • You will also need a syringe, which is used as a measuring device for dosing the oil. For such purposes an ordinary medical syringe of 10cc or more is suitable. It is desirable to have a precise measuring scale on the syringe
  • After preparing the necessary materials, you can proceed to the preparation of

Instructions for preparing the fuel mixture into the lawnmower:

    Fill plastic container first. The container should be filled with not more than 2 fingers so that the oil can fit in

After preparing the fuel mixture for the grass trimmer, it remains to refuel the tool, and get to work. How to properly fuel grass trimmers, lawnmowers, chainsaws and other types of motor equipment, let’s consider in detail.

ДOnly fresh gasoline is used for diluting and using in the trimmer.

How to mix oil and gasoline for a two-stroke engine

The peculiarity of two-stroke engines is that the fuel is filled into the tank along with the oil. Every time you refuel your machine, it is necessary to mix the fuel mix in the correct proportions before use. How to do it right? From our article you will learn how to dilute gasoline for a chainsaw, grass trimmer and other garden tools.

It is recommended to buy unleaded gasoline to operate garden equipment. Otherwise there is a risk of engine damage. Manufacturers advise fuel with an octane number not lower than AI-90, better AI-92 or AI-95. Consult the instruction manual for the specific recommendation for your tool. Fill the canister with the amount of fuel you need at the gas station. It is preferable to use metal: such a container does not produce static electricity from friction and so increases the safety of use.

Buy branded oils for two-stroke engines, preferably API-TB or API-TC. The manufacturer should indicate the recommended grade in the instruction manual of the tool. Also note their composition. Mineral oils are suitable for use in warm weather. Synthetic oils are better, they are less viscous and can be used even in freezing temperatures. Semi-synthetic are mineral with improved qualities, versatile for any season. For the temperature limit of operation, see the package. Also pay attention to the volume. What matters is not the proportion of gasoline and chain saw oil, but how much fuel mixture you need for one filling and how often you will work with the tool. If you own a chain saw, grass trimmer or chain saw and use one or the other thing several times a week, you should buy a large oil can of 3 to 5 liters. For several mowing during the garden season it is enough to take a bottle of 1 liter.

Mixing oil with gasoline

When you start working with a tool, the question always arises how much oil to add to gasoline for a chainsaw or grass trimmer. It is important to remember that for two-stroke engines the ratio is 1:50, t.е. 100 ml of oil for every 5 liters of fuel. Why it is important to observe the proportions? Excess oil contributes to the formation of carbon deposits on pistons and spark plugs, and its deficiency reduces the lubricating properties of the fuel mixture, which leads to the formation of scuffing on the piston group and increases the risk of engine failure.

The easiest way to determine petrol and oil proportions for your chain saw is to use measuring containers. They have a scale with markings on it that are easy to follow. Before pouring gasoline and oil in, be sure the container is clean. Do not get any water or dirt in the oil, as this can affect the quality of the fuel mixture. First fill petrol to the proper level, then add oil to the proper level. To mix the two, tilt the container several times. The fluids will mix quickly and the mixture will take on a uniform color, e.g. green or red (depending on the oil composition).

Important to Know! Never use plastic drink bottles for storing and mixing fuel mixture. Gasoline corrodes plastic. Even if the walls of the bottle seem to be intact, harmful components will get into the fuel mixture and together with it into the engine. This is very bad for the carburetor.

We recommend wearing gloves to protect your hands from the penetration of gasoline and oil. Also do not forget about the elementary rules of fire safety. Mix the mixture outdoors so that gasoline vapors do not accumulate indoors. Do not smoke while working and avoid other factors that can cause ignition of combustibles and lubricants.

Pour the prepared fuel mixture into the fuel tank and close the cap tightly. If you have blended more than you can use at one time, empty it into a separate canister for storage or leave it in the blending tank. Most important is that you close the cap tightly. The ready-to-use mixture can be stored for two weeks and used for refueling without risk to the engine. The only condition is that it must not be left in the fuel tank. If the tool will not be used for a long time. use up the leftovers completely or drain them.

Now you know how to dilute gasoline for a chainsaw so as not to harm the engine. Try doing it yourself. After you prepare the fuel mixture a few times, you will know how much you need, so you won’t have any extra mixture. You can buy everything you need in our online store. With branded oils your tool will last a long time.

How to mix

If you do not have a special measuring canister with divisions, which are included with each noteworthy grass trimmer, or such a container is lost, then use any suitable container. It is better to have a glass or metal. You can also use plastic, but you should choose a bottle with rigid walls.

The capacity of the container must be a multiple of 1 liter. You can take a 1.5 liter bottle, but practice shows that it is not very convenient. You also need a syringe, preferably 20 to 50 milliliters. First, gasoline is poured into the container, then a precisely measured amount of oil is added (by volume). The procedure must not be changed.

If you have “pre mix” oil, you need to close the bottle or canister with the cap, turn it upside down several times and shake it vigorously. If the oil is “self-mixed”, it dissolves on its own. Prepared mixture must be used over the course of a day. If you know how much fuel a grass trimmer uses for a certain amount of work (or time), it is not difficult to calculate the amount of mixture. If not, before each filling, dilute the new oil so that only a minimal amount is left over before the work ends.

Rules for mixing

And now about how to mix it correctly. But it would be more logical to begin with analysis of common, but absolutely unacceptable mistakes, which many owners of this mowing machine “sin” with. The following are considered mistakes in mixing the fuel mixture.

  • Adding oil to the fuel already in the brushcutter’s fuel tank. You won’t get a homogeneous fuel mixture that way. It might work, if only you shake the grass trimmer for a long time afterwards. But it is unlikely that someone would do this, given the weight of the machine.
  • Pouring oil into the mixing tank first and then adding gasoline to it. Gasoline has a lower density than oil, so if you pour it into the oil, it will remain in the upper layer, i.e. there will be no natural mixing. Of course, you can mix it afterwards, but it will take much more energy than if you do it the other way around. pouring oil to the gasoline you’ve poured in.
  • Ignoring precise measuring tools to take the necessary volumes of ingredients used. In other words, to dilute the amount of oil or gasoline “by eye” is a bad habit when operating motor vehicles.
  • Take empty drinking water bottles to prepare fuel mixture. Such containers are made of too thin polyethylene, which may be dissolved by gasoline.

Bearing all the above mentioned in mind we recommend to use the following rules when mixing the fuel mixture for the grass trimmer’s two-stroke engines.

  • Use only clean containers made of metal or special plastic for storing gasoline, oil, ready-to-use fuel mixture and its preparation.
  • Use a watering can for filling petrol into the thinner container to avoid spilling, and for adding oil use a measuring cup with volume indicators or a 5 ml and 10 ml medical syringe.
  • First pour petrol into the canister for preparation of the fuel mixture, and then oil.
  • To dilute the mixture, pour only half of the planned volume of gasoline into the canister first.
  • Then add to the gasoline all the amount of oil required to prepare the mixture.
  • Thoroughly mix the contents of the dilution canister. The best way is to stir stir in a tightly closed container in a circular motion. It is not known what kind of material it is made of, what kind of reaction it may have with the ingredients of the mixture and how clean it is.
  • Add the rest of the gasoline to the mixed mixture and stir thoroughly again.
  • You can fill the lawnmower’s fuel tank with a prepared mixture.

It should be borne in mind that the ready 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 thus deteriorates the performance of the grass trimmer.