How to Lubricate a Chainsaw With Oil
Unless you understand both types of chainsaw oil and how to use them, your chainsaw won't work properly for long. Here's what you need to know.
Every editorial product is independently selected, though we may be compensated or receive an affiliate commission if you buy something through our links.
A few hours
Chainsaws are great tools for many different wood cutting projects. Felling trees, trimming branches and cutting posts and rails for fences are just a few things for which I regularly use my chainsaw. Part of responsible chainsaw ownership involves caring for and maintaining your saw, and much of this comes down to oil.
To run properly, all chainsaws need two types of oil for different jobs. The first is engine oil. All chainsaws have two-stroke engines, so they need two-stroke engine oil mixed with their fuel to help cool and lubricate the moving parts inside the motor.
The second type of oil, called bar and chain oil, is for lubricating the chain as it cuts. Choosing the correct oils for these two jobs and adding them to the tool correctly is crucial to the performance and longevity of your chainsaw.
- 2-part divided gas can
- Slot-head screwdriver
- Socket wrench set
- 2-stroke motor oil for air-cooled engines
- Medium grade bar and chain oil
- Premium gasoline
Project step-by-step (6)
Remove chain guard
- Determine what size of socket you need to loosen the two nuts securing your chainsaw's guard over the chain and bar.
- Loosen and remove these nuts, setting them aside where you won't lose them.
- Slide the plastic chain guard off the bolts and set it to one side.
Clean inside the saw
- Use your slot-head screwdriver to carefully scrape away all the oily sawdust and dirt that's built up around the bar and chain. Be thorough.
- Turn the plastic saw guard over so you can see the inside face. Use your screwdriver to remove the dirt and gunk from all the nooks and crannies of the guard.
Replace chain guard and tighten chain
- Slide the chain guard back onto the two bolts protruding from the saw, making sure the chain remains in the narrow slot on the edges of the bar.
- Replace the two nuts you set aside earlier, and fasten them only finger-tight at first.
- With the saw sitting flat on the ground, swivel the bar up as high as it can go. At the same time, use your slot-head screwdriver to slowly tighten the chain by rotating the screw near the two bolts holding the guard in place.
- Tighten the chain until there's no slack around the bar, but it can still move freely back and forth if you pull it.
- Tighten up the two nuts all the way with your socket wrench.
Mix saw gas
- Choose and purchase a two-stroke engine oil meant specifically for air-cooled engines, not liquid-cooled. Several chainsaw brands make their own oil, like Echo and Husqvarna. I've been using Echo brand oil for my Echo and Jonsered chainsaws for about 10 years.
- Determine the ideal ratio of motor oil to gasoline for your particular saw. Start by checking the owner's manual. Many newer saws use a ratio of 50:1 or 40:1 gas to oil. Older saws usually require around 30:1.
- Using the measurement guide on the side of the oil bottle, calculate the precise amount of oil you'll need to make the quantity of chainsaw fuel you want at the ideal ratio of oil to gas for your saw. Then pour that amount of oil into the larger side of your divided gas can. Always add the oil first.
- Add the corresponding amount of premium gasoline to the gas can. For example, this gas can holds six liters on the fuel side, and 2.25 liters on the chain oil side. To make six liters of chainsaw fuel at a ratio of 40:1, you'll need 0.15 liters of two-stroke engine oil and 5.85 liters of premium gas.
Choose and prepare chain oil
- Purchase a jug of bar and chain oil for your saw. Chain oil comes in different viscosities for different temperatures. Personally, I always choose medium grade oil rated for year-round use. I use my saw during cold winters and hot summers, and have never had any lubrication issues.
- Open the jug of chain oil and carefully pour it into the smaller portion of your divided gas can.
Fill your saw
- Open the gas cap on your chainsaw. It will be the one nearest the back of the saw.
- Open the fuel side of your divided gas can. Carefully fill the saw's gas tank, then replace the cap and close that side of the can
- Open the chain oil cap on your saw. It's always close to the bar. Uncap the oil side of your can and carefully fill the saw's reservoir with oil. Replace the caps and your saw should be good to go.
- Keep the oil and gas tanks of your saw topped off. The tanks are sized to run out at the same time, so when your saw runs out of gas, it's also out of chain oil. Be sure not to forget the chain oil when you gas up.