Can I put machine oil in my lawnmower?

Can I put motor oil in my lawnmower?

Most modern lawnmowers use two-stroke, air-cooled gasoline motors. The working volume of the power units rarely exceeds 200 cubic centimeters. This design gives the machine moderate weight and efficiency.

In some cases, companies produce lawnmowers with water-cooled four-stroke engines. In this case, you should buy oil suitable for automotive engines. the construction of the engine in this case will not differ.

General Lawnmower Oil Recommendations

Based on the above features of engine design, it is best to use a special oil for lawnmowers for lubrication, and it must meet the temperature conditions in which the unit will be used. SAE 30 special grease is considered optimum. It is used at temperatures above 5 degrees.

What kind of oil to put in a lawn mower?

If specialty is not available, automotive grade greases can be used:

These lubricants are also designed mainly for positive ambient temperatures and a maximum value above 35 degrees.

By type of lubricant. mineral and semi-synthetic are permissible. Fully synthetic would be too expensive. The API performance level is “SF”, “SG”, “SH”, “SJ” and higher. For four-stroke garden equipment engines, the label should be labeled “4T”.

Read the label on the oil

SAE number is a code used to classify oil by viscosity. Viscosity is a measure of the fluid’s resistance to flow, sometimes called the “thickness” of the fluid. The lower the number, the easier the fluid flows. Motor oils are designated from 5 to 50.

Temperature can affect the viscosity of the fluid, so different oils are rated for winter, labeled with a “W”. Different classes of oil (e.g. 10W-30) can be used at both summer and winter temperatures, as the oil will not thicken at lower temperatures due to the additives.

Types of lawnmower oils

So what oil to put in your lawnmower? One factor to keep in mind is the climate of where you are. Different oils work best at different temperatures, and not all are suitable for your equipment.

Be sure to read the owner’s manual for the manufacturer’s recommendations for your mower. We’ve put together this guide to help you choose one of the common types of oil.


This is the most commonly used oil for lawnmowers, as it is ideal for temperatures between 4°C and 37°C. If it’s colder than 4 degrees outside, you hardly need to mow your lawn. Overall, this is the best choice for an inexpensive oil that you can use in your lawn mower from spring through fall.

SAE 10W-30

This oil has a wider temperature range, from.17°C to 37°C. Since this type of oil can withstand colder temperatures, it can also be used in other engines. For example in snow blowers. If used in temperatures above 28 degrees, oil consumption may increase.

SAE 5W-30

This oil performs best in temperatures below 4°C. So it’s perfect for your snow blower, but not for your lawn mower.

Synthetic SAE 5W-30

The synthetic version of the 5W-30 oil has a wide temperature range in which it can be used, from.28 to 48°C. This oil works year round. This oil makes the engine run better and lowers consumption, but it is also more expensive.

Synthetic SAE 15W-50

This oil also has a high temperature range, from.6 to 54°C, but works best at higher temperatures. It is usually used for commercial lawn mowing equipment.

The best oil for a lawnmower with a 4-stroke engine

Motors with 4-stroke systems determine how much oil is needed for fuel enrichment. You don’t have to calculate or mix anything by hand. You just pour the grease into the special tank and that’s it. Now you fill it up as you go. It’s convenient and practical, but these lawnmowers are relatively expensive, and if they break down, it costs a pretty penny to repair them. With oils, though, things are even easier. In fact, any summer motor oil with a viscosity of 30 units will do. But it’s better to use a specialised oil. It contains an extended additive package designed specifically for these engines, taking into account all their peculiarities.

Despite the fact that the overall design of four-stroke lawn mower engines similar to automotive, they still have important differences: in order to reduce the price of the product at lawn mowers excluded oil pump and generally the system of oil supply, it increases the requirements to the viscosity used in the motors of garden equipment. The engine oil in the lawnmower engine is distributed by the crankshaft: it is scooped out of the crankcase and sprayed onto the parts. Because of this design, the viscosity of the grease should be sufficient to keep the oil film on the parts, while at the same time it should not be too thick so as to interfere with the movement of parts or form a hard crust.

Lawn mowers, on the other hand, operate mostly at positive ambient temperatures and the load on their engines is not as severe as on car engines. Lawn mowers most often do not require a “cold start” in freezing temperatures, which greatly reduces the life of a car engine and requires low-temperature properties from the lubricant.

Even vice versa, lawnmowers are usually air-cooled and therefore have higher engine temperatures than liquid-cooled car engines.

The first filling is intended for running in of the engine. after five hours of work it is replaced, then on the new grease can work all season. Later on the oil is replaced according to the regulations after a certain number of hours, or it is refilled at the end of the dacha season and replaced with a new one the next year.

What oil to use in a lawn mower??

Everyone knows that the engine of the car needs special care, which will provide a long and trouble-free life motor. The same goes for the gasoline lawnmower motor: whether it’s a weed trimmer or a large four-wheel mower, you’re going to have a problem choosing the right oil. So what are the basic requirements for lawn mower engine oil?

As with any machine, the lawnmower has a manual, which prescribes not only the main characteristics of the tool, but also the rules of care for it. Thus, the instructions will say that only specialized oil should be used for lawn mowers. And some manufacturers even insist on using the same brand of oil as the lawn mower itself.

In fact, this fact turns out to be just a marketing move by manufacturers, and both car and motorcycle engine oil for four-stroke engines can be suitable for lawnmowers. It is enough to follow the basic rules:

The oil should be mineral or semi-synthetic. Fully synthetic oil can burn the motor, so it is best not to use it at all. Mineral oil produces a lot of sludge when your mower runs, so we recommend choosing a semi-synthetic oil. over, mineral oil is hard to find these days.

Oil viscosity should not exceed SAE 30 or 10w30, and the quality grade must range from SE to SJ. viscous oil can impair engine performance, but so can less viscous oil. These values are clearly written on the packaging.

Always select oil depending on operating temperature conditions. If you mow in cold weather, the oil viscosity can be higher than this, but you must change to the correct oil the next time you mow.

In lawnmowers with four-stroke engines, oil is poured into a special crankcase and never mixed with gasoline, as the design of such gasoline lawnmowers does not involve mixing oil and fuel. On the contrary, it can cause engine damage. It is enough to change oil once a season, as the sump normally holds 450 to 600 ml of oil. enough to treat large areas. However, do not be lazy to check the oil level before each use of the tool.

How oil is used in 2-stroke mowers?

As a rule, the two-stroke engine is installed on grass trimmers, and since their design does not imply the presence of extra parts, a separate container for oil is not provided. What to do in this case? Prepare fuel mixture.The same rules apply to two-stroke mowers as to their bigger counterparts, with one exception. you have to buy oil for two-stroke machines.

On each trimmer (or in its manual) there are proportions of mixing fuel and oil: from 1:32 to 1:35. This rule is valid only for mineral oil! Since it is now quite difficult to find, and the cost can discourage, semisynthetic or even synthetic oil is most often used. Please note that the mixing ratio in this case changes and becomes 1:50. If in doubt, look carefully at the oil package, which usually has these data on it. You should take your bearings from there. To prepare a mixture, it is enough to pour 100 ml of oil into five liters of gasoline, this should be enough for a whole season of regular mowing. If not, repeat the procedure.

How often should the lubricant be changed?

As noted above, the instruction manual for garden equipment with a 4-stroke engine must necessarily indicate the frequency of oil change. But if there is no instruction, then focus primarily on the number of hours worked by the technique (moto-hours). After every 50-60 hours worked out the oil in the engine should be changed.

However, when the area is small and you can handle it in time not more than one hour, it is unlikely for the whole spring and summer season mower will work even half of moto-hours of the norm, unless you rent it out to neighbors. Then the oil needs to be changed when the equipment is preserved in the fall before the winter period.

Oil change

Lubricating fluid should be changed in time, according to the maintenance plan, which is specified in the instruction manual of the particular model of lawnmower. On average the lubrication efficiency decreases after every 50 hours of operation. For the period when the mower will not be working, clean the oil filter and change the oil.

  • turn on the mower and allow the engine to idle for 15 minutes;
  • unscrew the plug in the tank opening;
  • put a container to catch the used oil;
  • tilt the unit to the side of the drain;
  • After draining the used material screw the cap back on;
  • the mower is placed on a level surface and the hole in the top is opened
  • fill up the oil to the required level, check the level by using the dipstick;
  • close the hole and screw in the plug.

Most machines have a fill volume of 500 to 600 ml.

Change of oil

Lubrication fluid must be changed in a timely manner, according to the maintenance plan listed in the owner’s manual of each mower model. On average, lubrication efficiency decreases after every 50 hours of operation. When the mower is not running, the oil filter should be cleaned and the oil changed.

  • turn the mower on and let the engine idle for 15 mins;
  • unscrew the plug in the tank opening;
  • put up a container to collect the waste;
  • tilt the device to the side of the drain;
  • after the used material has been drained off the plug is screwed in;
  • place the mower on a flat surface and open the opening from above;
  • pour in oil up to the required level, check the level with a dipstick;
  • the hole is closed and the plug is screwed in.

the quantity of liquid poured in is up to 500-600 ml for most machines.

Features of two-stroke and four-stroke engines

A two-stroke motor is similar in principle to a four-stroke engine. The peculiarity lies only in the fact that the stroke of two-stroke engine is carried out for 2 strokes, and for four-stroke. for 4 strokes. The latter is understood as a downward or upward movement of the piston. In this case there are 2 strokes per 1 revolution of the crankshaft. Working stroke of the piston is its movement, during which the energy of gases, resulting from the combustion of fuel, is converted into the useful work of the motor (its rotation).

Structurally and operationally, two-stroke and four-stroke models of internal combustion engines differ from each other according to the following criteria.

  • The two-stroke engines have the higher value of specific and liter power (approximately 1.5-1.8 times).
  • Lubrication method.
  • Four-stroke engines are characterized by greater fuel economy (fuel consumption is about 20-30% less), and their exhaust emission contains fewer toxic substances
  • The way the fuel mixed with atmospheric air is fed inside the cylinder and the exhaust gases are exhausted. The timing mechanism on 4-strokes is designed for this purpose: it opens and closes the valves when needed. 2-cycle models don’t have one.
  • Noise levels: 4-strokes are quieter.
  • Complexity of the machine: 2-stroke models are simpler.
  • 4-stroke models have a longer service life because of their improved lubrication system and the fact that the crankshaft rotates at a slower speed.
  • RPM acceleration: 2-stroke machines accelerate faster.
  • Easy to service and maintain and easier to maintain with a 2-stroke engine. Also this motor is cheaper in price and weighs less than its four-stroke counterpart.

Power density is the ratio of the drive unit’s power to its weight. The liter capacity is the ratio between the horsepower and the engine displacement (in liters).

The lack of a valve timing assembly makes two-stroke motors lighter and easier to set up. The cylinder is filled with fuel-air mixture and cleared of gas by expansion and compression through special holes: inlet (blow-out) and outlet.


When choosing an oil, you have to pay a lot of attention to the oil manufacturer. It is better to choose the brand recommended by the manufacturer of the lawnmower. The equipment owner’s manual provides information about the oil fill, oil change intervals, and recommendations for operating fluids.

Also, many lawnmower manufacturers produce their own oils, which will have to be used for replacement if you want to keep the warranty on the equipment. In addition, the manual provides general characteristics that the oil must meet. When choosing a fluid for replacement, you need to be guided by this list. This makes it possible to select an oil that meets the manufacturer’s requirements as closely as possible.

Many self-respecting manufacturers of lubricating fluids offer their consumers a separate line of products for the maintenance of garden equipment. If it is possible to choose such a special oil, it is necessary to buy it.

  • Among all the companies that represent their products in the Russian market, the best is Shell Helix Ultra. These oils are popular in all countries. For 40 years Shell specialists have been working on a unique technology of synthetic oil production from natural gas. The resulting product is characterized by an improved composition, which has no analogues at the moment. The manufacturer adds the necessary additives to the base composition, thus obtaining products with different characteristics. Such oil should be bought only at specialized points of sale, because there are often low-grade fakes.
  • Liqui Moly also provides high quality products. The manufacturer produces several product lines, which have different purposes. This range includes products for the maintenance of garden equipment. Such oils are designed for long-term work of trimmers and lawnmowers, their technical specifications are developed in accordance with the features of modern equipment and manufacturers’ recommendations.

Liqui Moly adds additives to lawnmower oils in order to reduce wear and tear and keep the engine clean. The main advantage of such liquids is the environmental friendliness, because they are made on a vegetable basis. Liqui Moly lawnmower oils comply with all environmental regulations.

Rasenmaher company produces a good lubricant of mineral type, which was specially developed for garden units. This product can be used to service 4-stroke engines with different cooling systems. The substance from Rasenmaher can only be used at temperatures above zero. The manufacturer has carefully designed and selected additives for his product. The result is a broad list of functionalities:

Oil for four-stroke engines

For petrol lawnmowers with four-stroke engines, lubricant must be filled into the opening in the cylinder housing and petrol into the petrol tank. The owner’s manual for each specific petrol or lawn mower contains recommendations for lubricant change intervals. Nevertheless, it must be remembered that the lubrication efficiency decreases after about 50 hours of total operation of the machine. In cases where small areas need to be mowed, even in one season, that many operating hours may not be accumulated. This means that the lubricant will only need to be changed to preserve the machine for the cold season.

The process of replacing the lubricant, step by step, looks as follows:

  • First of all, start the engine of the unit for 15 minutes at idle to warm it up (in this case the viscosity of the old substance will decrease and its fluidity, on the contrary, will increase);
  • Next, the oil plug on the crankcase is unscrewed;
  • The lawnmower itself is tilted in the direction of this drain, having previously substituted a container for collecting the used lubricant;
  • After the used material has drained out, the plug is screwed in;
  • The machine is set on a flat base;
  • Open the upper crankcase opening and pour in a new lubricating substance, its level is periodically checked with a dipstick;
  • When the level reaches the desired mark, the hole for filling tightly screwed plug (standard amount of grease can vary from 500 to 600 milliliters).

Professionals think it is possible (and practice justifies it) to use in four-stroke internal combustion engines not only the brands of oil recommended by the mower manufacturer, but also their close analogues. For example, the brand “10W40” may well replace “SAE-30”. Practically all lubricants of “SF” and higher grade are good enough for most modern mowers. Special cold-resistant grades should be used for conservation purposes.

Do not pour it directly into the soil, as it is harmful to the environment. It is better to use special containers for collecting “waste” and dispose of it at special landfills.

Rating of the best lawnmower oils for 2022

Lubricants for four-stroke engines

This lubricant has several protection levels, so if you buy it practically in any store you can be sure of its quality. Judging by the reactions, this fluid is of high quality and can be successfully used in appropriate engines. It contains a balanced set of additives that provide increased efficiency, and the medium consistency greatly extends the temperature range of application. Installed