Chain Saw Gas Oil Mix Ratio – Is 50: 1 For All. STIHL chainsaw oil ratio

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.

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.
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  • 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.

STIHL Chainsaw Fuel Mix Ratio

  • 1-liter gasoline mix with 20 milliliters STIHL oil,
  • 5l with 100 ml
  • 10 l with 200ml.

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.

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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.

How To Mix Fuel For a Chainsaw – Quick and Easy

Chainsaws need fuel to run. Without fuel, our chainsaws are just useless pieces of metal and plastic. Chainsaws (not including electric or battery units – which are actually a thing now) are powered by a 2 stroke engine that requires fuel mixed with a proper ratio of oil. If straight gasoline is run in a chainsaw it will likely result in catastrophic engine failure. Do not make this mistake. Make sure to mix your oil properly so that your chainsaw functions properly for years to come.

How to mix gas and 2 cycle engine oil for weedwhackers, chainsaws…

Mixing fuel for a chainsaw is done by combining the appropriate amount of 2-Cycle oil and Gasoline together in the proper ratio laid out in the owner’s manual for your particular chainsaw.

Different chainsaw manufacturers require different fuel ratio mixtures. Running the incorrect mixture can cause the chainsaw to either run too rich or too lean. Running rich means the fuel contains too much oil and can cause the unit to smoke, foul the spark plug or clog the muffler. Running lean means the fuel does not have enough oil and can result in the damaging of the engine by scaring the piston, cylinder, and rings.

STIHL, Husqvarna, Dolmar, Maruyama, and Echo typically require a fuel ratio mixture of 50:1 Poulan typically requires a fuel ratio mixture of 40:1 Please keep in mind that this is a general rule of thumb. Always consult your operator’s manual to be sure you have the exact fuel ratio mixture for your chainsaw.

Once you have determined the correct fuel ratio mixture you need to purchase the correct amount of oil for your chainsaw. You need to be sure to read the label for the volume of oil and the mixing ratio.

Refer to the chart below to make sure you’re using the correct 2-cycle fuel and oil mixture:

There are 2 more issues that need to be addressed with respect to fuel that most people do not realize.

The first of which is the age of the fuel in your gas can. Most people will mix fuel and let it sit in the garage for months. This is a formula for having a chainsaw that won’t run at all or at least won’t run correctly. Think of gasoline as you think of the milk in your refrigerator. You wouldn’t drink 3-month-old milk, would you? I didn’t think so. So why use 3-month-old fuel in your chainsaw? Gasoline expires the same as milk.

If gasoline is more than a month old, DO NOT USE IT in your chainsaw.

The second issue is the ethanol content in your fuel. What is ethanol you ask?

Ethanol, also known as ethyl alcohol is used as a biofuel additive in most of the fuel today. As a general rule of thumb, ethanol of up to 10% is generally ok for use in small engines like those that power chainsaws. Notice I said generally ok and not absolutely ok. Fuel with up to 10% ethanol will run fine but will cause issues with your chainsaw over time. These issues include the hardening and cracking of rubber and plastic materials like fuel lines, grommets, and seals. There is another grade of ethanol fuel known as flex-fuel that contains up to 85% ethanol.

Do not run flex fuel in your chainsaw. It will seriously damage or destroy the unit. Never run fuel with more than 10% ethanol in your chainsaw. At least not in the chainsaws we have today. I’m sure there are chainsaws being engineered that will be able to handle flex fuels just fine. However, they are not currently on the market for sale.

It is best to run ethanol-free gasoline, (if you can find it), with a high octane rating in your chainsaw. The higher octane-rated gasoline helps to combat things like pre-detonation within the engine.

What is the correct fuel mix for chainsaw?

The correct ratio of 2 cycle oil mix for chainsaws varies from brand to brand and must be strictly adhered to as to avoid damaging the chainsaws 2-cycle engine. What is the correct fuel mixture for your chainsaw?

Check with your chainsaws operator manual to verify the following information is still accurate as manufacturers update oil mix requirements from time to time

How much 2-cycle oil do you put in a gallon of gas for a chainsaw?

The correct amount of oil must be used to get the ratio of oil and gasoline correct in a 1-gallon fuel can. What is the correct amount of 2-cycle oil for 1 gallon of gasoline?

A chainsaw fuel mixture of 50:1 requires 2.6 oz of 2-cycle oil to be mixed in 1 gallon of gasoline. A mixture of 40:1 requires 3.2 oz of 2-cycle oil to be mixed with 1 gallon of gasoline.

Wrapping Up

Chainsaw’s 2 cycle engines are made with very tight specifications and run at very high RPMs that require properly mixed and fresh fuel. Always make sure that your gasoline is properly mixed with the correct ratio of oil for your particular brand and model of chainsaw. Remember that the wrong mix can destroy your chainsaw. Also, never use gasoline that has been sitting around for more than 1 month. Old fuel causes problems and it is best to just avoid it.

Have a great day and be safe.

Always be sure to only use EPA-approved fuel containers along with hand and eye protection.

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I have been part of the chainsaw and outdoor power equipment business in one way or the other for over 35 years. There are not many things that I have not seen in the business. From repairs, sales, equipment operation, and safety I can help you with your questions.

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STIHL HP Two-Stroke Engine Oil Mix

Want it by Tuesday 30th May? Order within 5 hours, 46 minutes and choose Parcelforce Next Day 12.00AM at checkout.

STIHL HP Two-Stroke Engine Oil is a top selling mineral oil two-stroke engine oil.

Specially developed for STIHL engines.

Excellent lubrication and combustion properties. Performance class: JASO-FB, ISO-L-EGB.

20ml of 2 Stroke wil mix 1 Litre of fuel

UK Delivery

Orders Over £75 Excluding VAT

Free UK Delivery on Orders Over £75 VAT

Standard DPD / Royal Mail 2-3 Day Service FREE

Orders UP TO £75 Excluding VAT

Standard UK Delivery Royal Mail Tracked 48 from. £3.00VAT

Standard DPD 2-3 Day Service. £7.99 VAT

DPD Next Day Service. £8.99 VAT

DPD Next Working Day Delivery Before 12. £13.00 VAT

Saturday Delivery. £13.00 VAT

Saturday Delivery Before 12. £16.00VAT

Delivery costs are calculated by weight at the checkout, the quoted are examples based on average order size.

In store and Local Delivery Costs

Should I Mix 2 Stroke Fuel At 32:1 For My Old Chainsaw? Teaching Apprentice Dave

Free in store Collection. Monday to Friday 8am. 5pm

Gustharts Local Delivery

We offer a local delivery service to a 30-mile radius from our showroom. Costs are dependent on distance from the showroom and are calculated on the checkout screen. The item will be fully assembled, the ideal amount of the correct oil and fuel added and function test the machine all free of charge. Our PDI means we are confident that your machine will work flawlessly when we deliver it to you.

Once the order has been completed we will contact you to arrange the delivery day and time, we look to deliver all items within two weeks if in stock.

Orders are processed Monday to Friday.

Bank Holidays, Saturday’s and Sunday’s are NOT classed as working days.

For example orders which are placed with the “Next Working Day Delivery” option before 2:30pm on a Friday will be despatched Friday and delivered Monday. If ordered Friday after 2.30pm or over the weekend the order will be despatched Monday for delivery Tuesday.

Some areas may be subject to a delayed service which could take longer to deliver.

Most items are delivered Monday to Saturday, 7.30am-6pm (although some of our carriers may deliver slightly earlier or later)

Delivery costs are calculated by weight at the checkout, the quoted are examples based on average order size.

EU Delivery

Please Note: Shipments sent to the European Union are sold exclusive of VAT and may be subject to local import duties and taxes payable by the purchaser. Due to customs processing outside our control, the below timescales are indicative based on shipment history. EU delivery can take up to 28 days to arrive.

All applicable customs and import duties and any other charges are the responsibility of the customer. We use a range of different courier services provided by DPD, UPS and Royal Mail. Our internal systems determine which service to use when shipping your order. Postage cost is calculated at the checkout, based on weight and size of your order. In order to deliver the best possible service, we may send your order with a different service to the one you select.

Please see table below for estimated delivery times shown in working days:

Country Standard / Tracked Delivery
Czech Republic

Rest of World Delivery

Please Note: Shipments sent outside of the UK are sold exclusive of VAT and may be subject to local import duties and taxes payable by the purchaser. Due to customs processing outside of our control, the below timescales are indicative based on shipment history. International delivery can take up to 28 days to arrive.

All applicable customs and import duties and any other charges are the responsibility of the customer. We use a range of different courier services provided by DPD and Royal Mail. Our internal systems determine which service to use when shipping your order. Postage cost is calculated at the checkout, based on weight and size of your order. In order to deliver the best possible service we may send your order with a different service to the one you select.

Please see table below for estimated delivery times shown in working days:

Country Standard / Tracked Delivery
Bosnia Herzegovina
Cayman Islands
Hong Kong SAR China
New Caledonia
New Zealand
Puerto Rico
Saudi Arabia
South Korea
Sri Lanka
Trinidad Tobago
United Arab Emirates
United States


Royal Mail Price £3.50 No upfront charge. will be deducted from your refund amount.

Please note. This service can only be used for items being returned for a REFUND Only, please re-order the correct size.

Create your return label, then either drop the parcel off at the nearest service point or arrange a collection from home. Once the return label has been generated you can either print the label, have the label brought with the postman on collection or scan a QR code to print the label when you drop off at the post office or Royal Mail customer service point.

Please Note Royal Mail only covers parcels up to a value of £100, in the event your return is lost we would only be able to refund you a maximum of £100, we recommend taking this into account when deciding whether to return with this service.

By creating a label and returning with Royal Mail on our account you agree to have the cost of the label deducted from any refund amount, this will be applied irrespective of the reason for return.

Returns Procedure

Returning or exchanging items

If in the unlikely event that you are not completely satisfied with your purchase, we are happy for you to return for refund or exchange items you are not satisfied with.

This is subject to the return and receipt of your goods being in its original condition and packaging within 30 days of order date.

Please print off and complete the returns form, filling in the relevant fields explaining what you want to exchange or return and why?

Please send this form back with the goods to return or exchange. We recommend you use a postal service that offers a tracked service, as it’s your responsibility to get the parcel back to us.

Returning damaged or incorrect items

If in the unfortunate case, you have received an item that you have not ordered or that has arrived to you in a less than satisfactory condition.

Please print off and complete the returns form above.

If you can return the goods to us, we will exchange and refund your postage.

In the instance that this is a heavy or awkward parcel to return, it may prove beneficial for us to collect the item instead.

For any further assistance, please contact email or telephone 01670 789701 to communicate with us further regarding any issues.

We are keen to maintain a high level of customer service and are on hand to assist you in any way we can.

Returns Address

Gustharts Ltd Returns, Unit 31, Milkhope Centre, Blagdon, Newcastle upon Tyne ,NE13 6DA

Refunds and Exchanges for all items, including faulty goods, can only be given within 30 days of receipt.

We will issue a FULL REFUND (Excluding delivery charge) on receipt, we will exchange the item for a different size / colour if preferred.

The items being returned are your responsibility until we receive them back.

As a recommendation and for your own protection, we recommend that you send the parcel using a delivery service that carries insurance or tracking.

If goods are returned to Gusthart’s due to being unable to be delivered, incorrect address or order refusal, but you wish for us to despatch the goods again, a further delivery charge will be incurred. In the event of additional charges, a member of the Gusthart’s team will contact you to arrange payment.

The cost of returning is your responsibility and is therefore non-refundable, unless deemed necessary.

What is the Correct Gas to Oil Mix for Chainsaws?

Chainsaws can be expensive machines, and if you own one, you are sure to want to keep it in good working order. If you have a gas-powered one, part of this will mean always using the correct fuel – and since most chainsaws are 2-stroke models, this will involve mixing up the right gas-and-oil mix.

What is the correct gas to oil ratio for chainsaws? Why do you need to mix gas and oil like this? And what happens if you don’t? Here, we have the answers to these questions and more to help you keep your chainsaw running the way you want it to.

If you want a quick preview of some of the stuff we’re going to be talking about, check out this video that introduces some of the main concepts.

Before we get into mixing oil for your chainsaw’s fuel tank, let’s take a step back and think about why we need to do this at all.

Chainsaw engines come as either 2-stroke or 4-stroke versions. Sometimes these are also referred to as 2-cycle and 4-cycle engines – it’s the same thing.

Without going deep into the mechanics of how chainsaw engines work, a 2-stroke engine produces power for every two strokes of the pistons while a 4-stroke engine requires four strokes to produce power.

In a 4-stroke engine, on the third stroke, oil is taken from a special oil reservoir and brought into the engine to lubricate it. Since there is a separate oil reservoir and a stroke dedicated to lubrication, there is no need to mix oil into the gas the engine runs on.

However, in a 2-stroke engine, this doesn’t happen. There is no separate oil reservoir and there is no stroke dedicated to the lubrication of the engine – and for this reason, to keep a 2-stroke engine running smoothly, oil needs to be added to the fuel.

What is the Correct Gas to Oil Mix for Chainsaws?

There is no standard oil-to-gas ratio across engines, and you will need to check the manual for your particular chainsaw. However, most 2-stroke chainsaw engines, as well as any other similar power tools, run on a mixture that is one part oil to 50 parts gas, 1:50

However, many run on a ratio of 1:40, and other optimum ratios are possible – this is why it is essential to check the requirements of your machine.

So what does this look like in practice? Just to give an example, a 1:50 ratio of oil to gas works out at 2½oz of oil to each gallon of gas.

When you make your oil-and-gas mixture, take care to measure the amounts as precisely as possible. If you don’t get it right, you can easily end up damaging the engine of your chainsaw.

However, having said that, if you do make a mistake, it is better to have a little bit too much oil than not enough, so if in doubt, you can be slightly generous when adding the oil to the mix.

And what happens if you forget to add oil to the fuel you put in your chainsaw? You will know about it very quickly. The engine will start smoking within less than a minute and if you don’t shut it off immediately, it is likely to suffer irreparable damage.

How to make a gas and oil mix

If you have a chainsaw with a 2-stroke engine, you can easily mix up your own gas-and-oil blend to use as fuel. There’s no special technique, and all you’ll need is a gas can and something to measure the volumes.

First, pour the required amount of gas into the gas can. Carefully measure out the required amount of oil and pour it in after. Close the cap on the gas can and give the whole thing a good shake to make sure the gas and oil are properly mixed.

You can now use the mixture in your gas can to fill up your chainsaw.

General tips about gas engines

If your chainsaw hasn’t been used for a while – say, for a couple of weeks but less than a month – give the whole thing a good shake before you fire it up. If you leave it sitting, the gas and oil will separate it, and shaking the chainsaw will ensure they are well mixed before you start it.

If you don’t use your chainsaw for more than a month, empty the fuel and refill it with fresh fuel. Gasoline doesn’t age well, and after a month it will begin deteriorating to the point where the chainsaw no longer functions correctly. If you try to use old fuel, you risk damaging your chainsaw’s engine.

If you don’t want to mix gas and oil yourself, you can buy premixed fuel to save yourself the hassle. If you do, make sure you choose one that is suitable for your machine.

Make sure you know what kind of engine your chainsaw has. If it is a 2-stroke engine and you forget the oil, you will damage the engine. However, if you have a 4-stroke engine, you should make sure you only use pure gas – otherwise, you will also risk damaging your expensive chainsaw.

Quite separately from engine oil, chainsaws need oil for chain lubrication. This is true of gas-powered versions as well as electric chainsaws and cordless chainsaws. Make sure you don’t forget to lubricate the chain.

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Always use the right ratio

As we said, while the most common oil-to-gas ratios are 1:50 or 1:40, there is no standard, so you shouldn’t just guess. Make sure you find out exactly what ratio your chainsaw’s engine requires and mix it up carefully and precisely. Similarly – and this goes without saying – make sure you know whether you are running a 2-stroke engine or 4-stroke engine before filling the tank and firing it up.

Chainsaws are expensive tools, and failing to use the right oil-and-gas mix – or pure gasoline in the case of a 4-stroke engine – is the quickest way to send you valuable machine straight to the scrapyard.

Don’t forget to pin it!

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:

  • 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.

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