50: 1 VS 25: 1- Which Oil Mixer Is Better Option For You. Chainsaw gas oil mix

Chain Saw Gas Oil Mix Ratio – Is 50:1 For All?

The chainsaw is one of the most used cutting tools in woodworking. So when you use it, you should know how much gas and oil should be mixed together. There are few mixing ratios that you can minimize fuel consumption and increase performance well. So let’s see in detail about chainsaw gas mix ratios with the correct proportion.

Most chainsaws need a 50:1 fuel/oil mix ratio (2.6oz oil per gallon) for the 2-stroke engines. Some chainsaws require a 40:1 fuel/gas ratio (3.2oz oil per gallon). In order to reduce the inside friction and heat, older chain saws use a 30:1 fuel oil ratio.

The gas mixing ratio depends on the type of chainsaw and cc. When you mix oil with gas, you should have fresh fuel (gas) which is not older than 06 weeks. So let’s see, how to mix the oil with fuel in chainsaws properly with its effect. So let’s keep reading on.

Chainsaw Gas Mix Ratio

What Is 50 To 1 Gas Mix Ratio?

When your chainsaw’s manufacturer recommends a 50:1, fuel-to-oil mix ratio, you need 50 parts of gasoline need to mix with one part of oil.

If you mix one liter of fuel at a 50:1 ratio, you have to add 20 milliliters of oil. It is easy to calculate the 50:1 fuel-to-oil ratio.

which, mixer, better, option

When you move to other gas mix ratios such as 40:1, 32:1 and 25:1, the below conversations will help.

  • 1 gallon = 128 ounces, So 1 gallon needs 2.6 ounces of oil
  • 1 liter = 1000 milliliters, So 1 liter needs 20 milliliters of oil

Gas to oil 50:1

Chainsaw Gas Mix Ratio Table

Chainsaw engines are 2-stroke engines. So we should use additional lubricants with fuel in order to control heat and friction inside. So mostly, the gas mix ratio for the chainsaws is 50:1. You can follow the below table when you mix oil with gas. Chainsaw fuels

When we mix oil with fuel, we can see, many types of oil in the market. So let’s see, how to choose the suitable oil which is highly compatible with the chainsaw engine.

  • Simple mineral oil – Derives from fossil oils
  • Synthetic oil – Mix mineral oils and additives such as detergent and stabilizers to burn better
  • When you use gasoline, it should have a minimum of 89% of octane and no more than 10% ethanol content. If your octane rating is below 89% may increase the engine temperatures.
  • When the ethanol content is more than 10% will cause running problems and major damage in the engine.
  • If you use various ethanol content fuels, you should adjust the carburetor because it affects the engine speed.
  • Shake well after you mix oil with fuel

Synthetic oil is really good for chainsaws. Because it produces lower deposits and emissions due to lower ash content, sometimes, mineral oils can contain non-lubricants and solvents and additives that allow easier gasoline mixture. But it causes a higher amount of emissions, and sometimes those can harm the environment. These best 2-stroke oils will run your engine smoothly.

Can You Use Only Gasoline In Chain Saw?

Do not use only gasoline in chainsaws

You can’t use only gasoline in chainsaws because the chainsaw engine is a 2-cycle engine. We called this is a 2-stroke engine. When only gasoline is combusting inside lot of heat is generated. And there will be high friction. Due to this, engine heat will go up and inside parts, rubbers, bushes, and rings can be melted easily due to heat.

So do not let destroy the engine without using only gasoline. By accident, if you fill the chainsaw in a gas station, don’t forget to mix the oil (2T).

Can you Fill Chainsaw Directly from Gas Stations?

Gasoline comes with ethanol. Ethanol is an alcohol, and it attracts water, so it pulls water into your fuel system, which is bad for your chainsaw’s engine.

Secondly, olefin chemicals can find in your regular station gas. That chemical produces a gummy kind of residue and varnish kind of stuff in your carburetor and damages your carburetor.

With my experience, I would like to recommend you to use ethanol and olefin-free gasoline, which is good for your chainsaw’s life.

What Happens If I Mix Too Much 2-Stroke Oil?

Proper Gas-to-Oil mixture color

When you add too much oil to the fuel mixture for chainsaws, You can see smoky exhaust leaking out of the muffler and sometimes loss of power. So those problems can fix easily by replacing fuel in the tank.So always mix the fuel and oil according to the recommended ratio.

Additionally, when you add too much 2-stroke oil in your chainsaw, carbon, and oil will be deposited. So it clogs the whole system, and air can’t move in-out. So the engine will overheat rapidly.

And also, because of too much oil you will get a huge carbon build-up right on the piston and exhaust port, and it’s eventually going to break off, and it’s going to get stuck between the piston and cylinder, it is causing to piston and cylinder’s long run score up. So most suitable for using a manufacturer guide and use a suitable mixing ratio like 50:1, 40:1, or 32:1 as your manufacturer guide.

Tom Mackency

Hi, I am Tom Mackency. It has been 10 years that I have been working as a professional woodworker since 2013. I am really enjoying my carrier by creating many kinds of projects in my workshop. But mostly I like for home improvement projects. Home improvement and DIY projects are the most interesting things for me. than that, the coolest things are power tools. Those are very precious and efficient than a decade ago. So I try to introduce so many things about power tools, woodworking, DIY projects, home improvement and many more interesting topics here.

:1 VS 25:1- Which Oil Mixer Is Better Option For You

Using a proper oil mix ratio is very important for the engine. Because mixing too much oil can cause failure to burn gasoline properly. Otherwise, if you don’t use the right amount of oil, it’ll wear the engine out.

So how do you know which oil mixture will be best for you to use, 50:1 vs 25:1?

As you see, the 50:1 oil mixer uses 1 drop of oil per 50 drops of gasoline. So, naturally, the 25:1 mixer is thicker and travels slower than the 50:1 ratio. For the fast flowing, 50:1 oil mix is popularly used by the current manufacturers. On the other hand, the 25:1 oil mix is the older technique, and at present, it is used mostly on older engines.

To learn more about 50:1 vs 25:1 and their differences, stay with us till the end of this article. Here’s what you need to know to make a choice.

50:1 vs 25:1 Comparison Table

Detail Comparison Between 50:1 VS 25:1

If you want to learn deeply, there is no other way but to read the comprehensive comparison between the two. After reading the whole discussion, you’ll definitely be able to conclude.

Oil Density and Lubrication

A 50:1 oil mix ratio determines 50 units of gas mixes with one unit of oil drop. Similarly, 25:1 means 25 units of gas for a single drop of oil.

25:1 oil mix is denser, and it offers more lubrication than 50:1. So it’s a good choice for an older engine. Otherwise, 25:1 oil mixes produce lots of emissions since too much oil can’t be burnt properly.

Besides, the lubricant of the 50:1 oil mixer is enough for newer engines.

Verdict: 25:1 for older engines and 50:1 for newer engines.


Viscosity refers to the overall flow defiance of a liquid. That’s why honey has better viscosity compared to water.

However, as the 50:1 oil mixture moves very fast so it’s a perfect match for the 2-stroke engine as they wear out very fast.

Typically, a 2 stroke engine features a high revolutions per minute (RPM), which requires lubrication at the right time. If the oil is unable to reach in time, its piston will get scratched.

Speaking of 25:1, if you want a better flow resistance then look for a 25:1 gas/oil mixture. The viscosity of 25:1 is the ideal match for older chainsaws. As older chainsaw models demand more lubrication, their 25:1 ratio can provide more than enough.

However, viscosity varies in different grades of oil. Remember these numbers are the vital factor in mixing and are called SAE grades.

Verdict: 25:1 for older chainsaws and 50:1 for newer chainsaws.

How To Mix 50:1 or 25: 1 Oil Ratio?

Till now we have only learned the benefits and shortcomings of both ratios. But how do you mix a 50:1 or 25:1 ratio?

50:1 and 25:1 Ratio Formula (Imperial Method)

In this imperial method of mixing the two ratios, you just remember two values and calculate them.

  • For a 50:1 ratio, you’ll need 1 gallon of gasoline for 2.6 fluid oz of oil
  • For a 25:1 ratio, you’ll need 1 gallon of gasoline for 5.2 fluid oz of oil

Here we showed a small chart in imperial units that helps you to understand the formula.

Following the chart now you can easily calculate and determine the correct amount of oil you require. However, if you find this a bit of a hassle, you can also buy pre-blended fuels. They will save your time as well as you can begin your job quickly.


There is no internal oil reservoir system in the 2-stroke engine. The oil directly mixes with the fuel. It acts as both the lubricant and fuel at the same time. So when too much oil is added to the mixture, it creates a smoke emission.

Yes, 2-stroke oil expires over time. Typically, the sealed 2-stroke oil takes up to 5 years to expire. But for the open stroke oil, the expiration date might not be longer than 2 years. However, when you mix oil with the fuel, try to use this mixture within 2-3 months.

How long does 2-stroke oil last once open?

Once you open the 2-stroke oil it’s better to go in 2 years after opening. Otherwise, it will expire and be unable to be used further.

What do 50:1 and 25:1 refer to?

50:1 and 25:1 refer to the ratio of gasoline to oil that should be used in two-stroke engines. For example, a 50:1 ratio means that 50 parts gasoline should be mixed with 1 part oil.

Which ratio should I use for my two-stroke engine?

The ratio you should use for your two-stroke engine depends on the manufacturer’s recommendations. Some engines require a 50:1 ratio, while others may require a 25:1 ratio. Check the owner’s manual or contact the manufacturer for guidance.

What happens if I use the wrong ratio?

If you use too much oil (a lower ratio), the engine may produce more smoke and carbon buildup. If you use too little oil (a higher ratio), the engine may suffer from inadequate lubrication and increased wear and tear.

Can I switch from 25:1 to 50:1, or vice versa?

Again, this depends on the manufacturer’s recommendations. Some engines may be able to handle a change in ratio, while others may require a specific ratio for optimal performance. Check the owner’s manual or contact the manufacturer for guidance.

How do I mix gasoline and oil for my two-stroke engine?

To mix gasoline and oil for a two-stroke engine, first determine the ratio required by the manufacturer. Then, add the required amount of oil to an empty gasoline container, and slowly add the gasoline while stirring. Finally, pour the mixed gasoline and oil into the fuel tank of the engine.

Can I use pre-mixed gasoline and oil in my two-stroke engine?

Yes, pre-mixed gasoline and oil is available for two-stroke engines. However, it may be more expensive than mixing your own fuel, and you should still ensure that the ratio is appropriate for your engine.

50:1 vs 25:1 Which Is Better?

With the blessings of science and technology now you can get better lubrication in lesser viscosity. At present, synthetic oil is getting much more popular as it is quite efficient in lubricating anything.

Though a 50:1 oil mix is absolutely enough to run an older 2-stroke engine, using a 25:1 oil mix is the safer option. As you know, manufacturers know their products better than others. So you should always use the oil mix according to your manual instruction.

While using 50:1 might have some risks, using 25:1 will keep your engine always safe. So if you prioritize your safety more than efficiency, consider using a 25:1 oil mix.

Final Words

So that’s all about 50:1 vs 25:1. Hopefully, we provide you with all the necessary information for 50:1 and 25:1 oil mixes. Now, you can easily decide which one is better for you and what you should do next.

Carefully and properly mix the oil. Share your thoughts with us in the Комментарии и мнения владельцев and help your friends to reach this helpful guideline.

I’m a woodwork enthusiast and have loved to do DIY projects since my teenage. Till then, I have learned the ‘Art of Wood’ to rejuvenate my home interior, plumbing, and fixing. My blog woodpander.com leads information, for woodworking interested guys or just curious to know about woodworks.


Hello, I’m a woodwork enthusiast and have loved to do DIY projects since my teenage. Till then, I have learned the ‘Art of Wood’ to rejuvenate my home interior, plumbing, and fixing. My blog woodpander.com leads information, for the woodworking interested guys or just curious to know about woodworks.

Can You Use 50 To 1 In 40 To 1? [Detailed Explanation]

Are you confused about using a fuel mixer on your chainsaw? This can be especially true when you buy an old chainsaw and don’t know what type of fuel mixer the manufacturer recommends using.

Modern chainsaw engines are usually 2-cycled, 2-stroke. Most companies recommend using a 50 to 1 or 40 to 1 fuel mixer in this type of engine. But for those who are unsure about the specific recommendations of the company, the question comes from them; can I use 50 to 1 in 40 to 1?

Yes, you can use 50 to 1 instead of 40 to 1 fuel mix to your chainsaw. Although in uncertain situations one should go for a mixer with higher oil content, a 50-to-1 mixer can improve the chainsaw’s engine performance. For this reason, many experts recommend a 50 to 1 fuel ratio.

Here, I will discuss the fuel ratios used in chainsaws. If you want to know about using the right fuel mixer for chainsaws, this article is for you. Let us dive deeper into the article by understanding both fuel mixers.

Will my chainsaw last longer if I use more oil? Is it safer? (25:1 VS 50:1 temperature testing)

What Is The 50 to 1 And 40 To 1 Ratio Oil Mixture Actually?

A 50 to 1 or 50:1 ratio oil mixer refers to a mixture of 50 parts gasoline and 1 part oil. It is relatively light and helps the 2-stroke engine to run more efficiently. Many chainsaw manufacturers recommend this mixer for their best chainsaws.

Besides, a 40 to 1 or 40:1 ratio oil mixture refers to a mixture of 40 parts gasoline and 1 part oil. This fuel ratio is a little thicker than the 50:1 blend. As a result, it generates somewhat less heat, helping chainsaws run more smoothly. As a result, this fuel ratio is more popular.

What Is The Difference Between 40:1 And 50:1 Gas Mixture?

The fundamental difference between both gas mixtures is the density of the fuel. A 40:1 oil mixture ratio is slightly thicker. It generates less heat and results in less piston wear. 40 to 1 oil mixture is better for operating the chainsaw for a long time.

A 50:1 gas mixture is slightly lighter than a 40:1 ratio. It generates a little more heat and wears the piston more. But the advantage of this fuel ratio is that it increases the efficiency of the engine even more. However, fuel consumption is also high in this ratio.

Why Does 2-Cycle Engine Require A Mixture Of Gasoline And Oil?

2-cycle engines complete two cycles in one revolution of the crankshaft. Besides, if we consider the working method of a 4-cycle engine, it completes its four cycles by 2 crankshaft revolutions. 2-stroke power engines have relatively fewer moving parts, making them lighter and stronger.

4-cycle engines include a separate oil pump as a lubrication method that takes power from the engine. This pump helps reaches engine oil through belts and pulleys to the moving parts and lubricates them. That’s why those moving parts run smoothly, and the engine stays cool.

But, 2-cycle engines do not have a separate oil pump like 4-cycle engines. Although this makes it convenient to mount them in any position and even upside down, a lubricating system remains lacking.

A mixture of gasoline and oil acts as a fuel as well as a lubricant. This type of mixture prevents excess heat generation. Therefore, 2-cycle chainsaw engines always use a mixture of gasoline and oil.

Is It Ok To Use 40 To 1 Fuel In 50 To 1 Engine?

Yes, you can use a 40:1 oil mixture in a 50:1 engine with no hesitation. Although there is some variation in density at both fuel ratios, it is tiny and worth neglecting. Also, this 40 to 1 ratio will help keep your chainsaw’s engine relatively cool and last longer. A ratio of 40:1 instead of 50:1 may be ideal for you, especially if you want to save fuel.

What Oil Ratio Is Better For A 2-Cycle Chainsaw Engine?

Honestly speaking, both 50:1 and 40:1 oil ratios are best for different types of chainsaws engines. But the selection of oil ratio will depend on your requirement or satisfaction. That is, in different situations, oils with different ratios can give you more benefits.

When you need more power from the engine or need to operate the chainsaw at higher rpm, use a 50:1 oil ratio. Since this ratio is lighter, the performance of the engine will also improve.

Also, when you need to operate the chainsaw with fuel economy at average rpm, 40:1 may be the best choice for you. As this oil ratio makes the engine less hot and saves fuel, you can work for longer hours without interruption.

which, mixer, better, option

How To Make 40 To 1 And 50 To 1 Oil Mixture?

40 to 1 ratio or 50 to 1 oil ratio is very easy to make. You will need ethanol-free gas, synthetic oil, a measuring cup, and an empty gas can. I will describe here how to make both of these oil mixtures. According to this ratio, you can make your required amount of oil mixture.

To make a 40:1 ratio, use one gallon of gas and 3.2 oz of synthetic oil. Similarly, you will need 8 oz of oil with 2.5 gallons of gas. Measure the correct amount of gas and oil into the empty gas can using a measuring cup.

Now close the gas can and shake it well. Keep shaking until both ingredients are well mixed. When the ingredients are mixed well, your oil mixture is ready to use.

You should follow the same procedure to make a 50 to 1 ratio oil mixture, only the ratio of gas to oil will be different. This ratio requires you to use 2.6 oz of oil per gallon of gas. In the same way, you will need 6.4 oz of synthetic oil for 2.5 gallons of gas.

What Has Oil; 40 To 1 Or 50 To 1?

A 40 to 1 ratio contains more oil than a 50 to 1 ratio. Whereas, a 40 to 1 ratio contains one gallon of gasoline with 3.2 ounces of oil, a 50 to 1 ratio contains about 2.6 ounces of oil.

What Is The Problem With Using Regular Gas In A Chainsaw?

The problem with using regular gas on a chainsaw is that it tends to overheat the engine. Because of this, the engine wears down quickly and can even be completely damaged. Also, since these engines are 2 cycles and have no separate lubrication system, the engine cannot run smoothly using only gas.

What Kind Of Oil Should You Mix With Gas For A Chainsaw?

Experts recommend always mixing synthetic oil with gas for chainsaws. Since the oil has to operate at high temperatures, conventional oils may not perform well. On the other hand, quality synthetic oils help the engine run smoothly.

Final Thoughts About Using 50 to 1 in 40 to 1

Both 50 to 1 and 40 to 1 ratio oil mixtures are suitable fuels for your chainsaw’s 2-cycle, air-cooled engine. You can switch from one of these to the other at any time. You should use the oil ratio as per your requirement.

Earlier chainsaws used more varied oil ratios, such as 32:1 and even 16:1. But the history of chainsaw engines have improved a lot, which is why the recommendations for mixing ratios of the oils used in them have also changed.

Hopefully, I have cleared up all the confusion about using the right oil mixture for your chainsaw.

Hi, I am Jose Wilson. I am an avid DIY woodworker. I love to try out new woodworking tools. In over 25 years I have tried several Woodworking tools including Chainsaws, Circular saws, Table saws, and Jigsaws among the rest. I also learned that many people didn’t quite understand how to use these tools. I want to help peoples to learn the use, benefits, and how these woodworking tools operate. I have created a number of work-tools s, built websites, and developed social media pages. Follow me on my social media.

STIHL Chainsaws Fuel Mix Ratio

If your car runs on regular gasoline, you would never even think of putting diesel fuel in your tank. Likewise, you wouldn’t try to run a flashlight on D batteries when it takes AA batteries. That’s because trying to operate any electronic device or tool with the wrong power source can be, at the very least, ineffective. In some cases, using the wrong fuel can even be damaging and dangerous.

Using the right fuel mixed with the accurate ratio of components is essential for the safe and efficient operation of your chainsaw. STIHL gasoline-powered equipment uses a 50:1 ratio of gasoline and 2-cycle engine oil. Learning how to mix your fuel properly is important in keeping your chainsaw in excellent condition over time.

Before You Begin

Before you begin mixing, make sure you’ve read the manual that came with your specific chainsaw for information on any unique needs it may have. If you lost your manual, online versions are available on STIHL’s website.

Make sure you use a gasoline container specifically created for this purpose. No-spill receptacles reduce splashes, spilling, and evaporation. When choosing which gasoline to use, keep in mind that this isn’t the place to skimp.

Unleaded gasoline with a minimum octane rating of 89 is recommended. A lower octane can cause some issues, such as increased engine temperature, increased piston seizures, and engine damage. STIHL offers 2-cycle oils made especially for STIHL chainsaws. Premium quality 2-cycle fuels provide protection for your engine.

Mixing Ratios

All STIHL equipment operates on a 50:1 ratio. Use the below as a guide for creating your mixture:

  • 1 gallon of gasoline 2.6 fluid ounces of oil
  • 2.5 gallons of gasoline 6.4 fluid ounces of oil
  • 5 gallons of gasoline 12.8 fluid ounces of oil

Pour the oil into your gasoline container before adding the gasoline. Close the container and shake it thoroughly to ensure it mixes together.

Usage and Storage

Before fueling your chainsaw, make sure you clean the fuel cap and the area around it to keep any debris or dirt from getting into the fuel. Position the machine so that the fuel cap faces upward. Remove the cap slowly, so any pressure that has built up can be gradually released. This precaution can minimize the risk of getting fuel on your skin or inhaling dangerous fumes.

Only mix enough fuel to last you one to three days at a time; this limit keeps the fuel fresh and minimizes the risk of any buildup. Never store fuel for longer than three months. If your fuel has been sitting for any length of time, shake the container to mix it up again. Storing the mixture should be done with care, away from anything flammable and away from your home.

Other Tips

If you find mixing to be too time-consuming or annoying, STIHL does offer customers other options to run their chainsaws, such as STIHL MotoMix, a pre-mixed, high-performance fuel that is ready to use straight away, eliminating the need for measuring, shaking and storing. Whether you purchase a pre-mixed fuel or mix your own, following the correct ratio can keep your chainsaw working properly and keep it working for years.

Correction—May 6, 2023: An earlier version of this article included an error in one reference to the fuel ratio. It has now been corrected.

What Type of Oil for a Chainsaw?

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Chainsaw oils are essential to keeping your chainsaw running well. Understanding the different types of oils can help you choose the right one.

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Just like your car’s engine depends on oil to keep it running smoothly, your gas-powered chainsaw engine needs oil to operate at its best. Different chainsaws require different oils, and using the wrong oil or not enough oil can cause major problems.

Knowing the available chainsaw oil options, learning how to choose the right one and determining the right fuel/oil ratio can help ensure your chainsaw runs smoothly every time.

Why Is Chainsaw Oil Important?

According to Nancy Egelhoff of Egelhoff Lawnmower Service, Inc., oil keeps a gas-powered chainsaw engine’s parts moving smoothly. “If you don’t have oil, you could destroy the engine,” she says. “If there’s no oil in the cylinder and piston of the engine, it will heat up so badly that it will score the cylinder and piston, and you will ruin the saw.”

Egelhoff says the damage might not be immediate. Some customers have seen damage occur as much as six months after they’ve forgotten to put oil in their chainsaw.

Common Issues if Chainsaw Oil Is Bad

Chainsaw engine oil can go bad. Two-cycle oil is good for up to five years when sealed, and many manufacturers list the oil’s shelf life on the container. Once opened, that oil will only have a shelf life of two years.

When you open a container, record the date on the container so you can throw out the oil if it’s not used within two years. Exposing oil to drastic temperature changes and moisture can also make it go bad.

  • Deterioration of engine parts, including the carburetor, gasket and fuel line.
  • Overheating, stalling or shutting down.
  • Operation and performance problems including power loss.
  • Vapor lock and problems restarting.

Choosing Chainsaw Oil

When shopping for chainsaw engine oil, you may notice that some brands cost more than others. While this oil is all basically the same, Egelhoff highlights the importance of buying a product you can trust. If you see a real deal on engine oil that’s much less expensive than name-brand oil, it could be a lower quality product.

“If it’s an off-brand, you don’t know where it’s made, and the manufacturer might not back their product,” she says.

When choosing chainsaw engine oil, you’ll need to know if you have a two-cycle or four-cycle engine.

Four-cycle engine

With a four-cycle engine, you’ll put oil and gas into separate reservoirs. Four-stroke oil goes in four-cycle engines. It contains special additives and base oils that support the stages of the four-stroke engine (the intake, compression, power and exhaust stroke).

Two-cycle engine and the gas-to-oil ratio

For a two-cycle engine, you must mix gas and oil together in a specific ratio. Old chainsaws, manufactured prior to 2003, require a 32:1 ratio. Chainsaws manufactured after 2002 usually require a 40:1 or 50:1 ratio. Check the two-cycle engine housing to see if it specifies the appropriate ratio. If you can’t find it there, refer to the owner’s manual.

Vince Christofora, owner of Woodstock Hardware in Woodstock, New York offers this advice. “One thing we do for our customers who buy a chainsaw that requires an oil/gas mix is we have them buy a gas can and we write the formula right on the can with a big black Sharpie. Then, the next time they need to make the mixture, they can dump in the right amount of oil and take the can to the gas station and pump in the right amount of gas.”

Here’s what can go wrong if you don’t have the right gas-to-oil ratio:

  • Not enough oil in the gas mixture results in not enough lubrication inside the engine. The chainsaw will not run properly and you will damage the engine.
  • Too much oil in the gas mixture can produce a smoky exhaust, oil leaking out of the muffler and even loss of power. This can cause the chainsaw to shut down.
  • If it is an emergency and you do not know the proper gas-to-oil ratio, you are better off mixing too much oil than not enough.

To simplify things and avoid the whole gas-to-oil ratio issue, Egelhoff says many of her customers buy STIHL MotoMix, a premixed fuel/oil product.

“There are several things that make this a brilliant product,” she says. “There’s no ethanol, and that’s the worst thing for small engines since it deteriorates lines, loses its spark very quickly and can separate out so you’re introducing both water and gas into the engine.” STIHL MotoMix has a two-year shelf life.

How To Check Chainsaw Engine Oil

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If your chainsaw has a two-cycle engine and you’ve properly mixed the gas and oil, checking your oil is as simple as verifying you have plenty of the gas mixture in the tank.

“Some chainsaws have a translucent tank so you can easily see the level of the gas mixture in the fuel tank,” Christofora says. “For those that do not, add some fuel and then check the fuel level by looking in the tank opening. If you are doing a small job a half a tank of fuel will be more than enough. If you have a big job or long day ahead of you, you may want to fill the tank right to the top.”

If your chainsaw has a four-cycle engine, you’ll need check the oil with the dipstick:

Correct Way To Mix Gas and Oil For a ChainSaw, WeedEater etc.

  • Put your chainsaw down on a level surface.
  • Remove the dipstick, wipe it clean and reinsert it.
  • Pull out the dipstick again and look to see where it’s completely covered in oil. This indicates your oil level.

How To Change Chainsaw Engine Oil

The exact steps to take when changing your chainsaw fuel/oil will depend on the model, but the following steps outline the general process:

  • If the chainsaw won’t be used for more than 30 days, drain the fuel tank. You can drain the old fuel/oil mixture into a gas can. (Remember, the oil is mixed with gas and this mixture needs to be stored in a gas-appropriate container.) You can then dispose of the mixture at most local hazardous waste centers.
  • Once the fuel tank is drained, tighten the gas cap and let the chainsaw run until it stops.
  • The next time you use the chainsaw, prepare a fresh gas/oil mixture.
  • Add that mixture to the fuel tank and tighten the fuel cap.

If you’re working with a four-cycle engine, you will need to change the oil because it’s separate from the gas:

  • Place a container, like an oil pan or an old plastic storage container, underneath the oil tank and open the oil tank cap.
  • Wait for all the oil to drain into the container.
  • Refill with fresh oil and close the cap.
  • Wipe up any spilled oil.

It’s always wise to refer to your owner’s manual for details and directions specific to your chainsaw.

Bar-and-Chain Oil Basics

Besides chainsaw engine oil, you’ll also need to keep your chainsaw supplied with bar-and-chain oil. This helps keep the chain lubricated, makes it easier to cut and helps keep your chainsaw from wearing out quickly.

Bar-and-chain oil types

Bar-and-chain oil comes in two types: summer and winter. Egelhoff explains that summer and winter oils have different viscosity. Winter oil is thinner, allowing it to run smoothly even in cold temperatures and when stored for awhile. Summer oil is thicker, heavier and formulated to work in hot conditions.

How to check bar-and-chain oil

A chainsaw uses bar-and-chain oil as it runs, and you’ll need to add about one tank of this each time you go through a tank of fuel. It’s easiest to keep up with your bar-and.chain oil by filling the reservoir every time you fill up the fuel tank. Many chainsaws have a bar-and-chain oil reservoir with a level gauge that lets you see how much oil is in the reservoir.

Note: Biodegradable, biobased, chainsaw oils (bar-and-chain and engine oils) have become popular in recent years because of the environmental impact of petroleum-based oil products. Consider these more earth-friendly products when buying oil for your chainsaw.

Paige is a copywriter and content writer who lives in Western Massachusetts. Her work has appeared in American Veterinarian, Business Insider, and more. Paige is skilled in writing about detailed topics, and she enjoys writing content that improves readers’ lives.