Most brands of lubricating chain oil sold in North America are petroleum-based. These oils are known carcinogens. In addition, prolonged exposure to petroleum-based oil mist can cause irritation of the respiratory tract. Environmental damage caused by petroleum-based oil spills is well known.

Now that firewood gathering season is upon us, the time is right to switch to an environmentally benign alternative to petroleum-based chain lubricating oil – common vegetable oil. I’ve switched to using vegetable oil exclusively for chain lubricant, and here are my observations and a few tips.

Advantages of replacing chain oil with vegetable oil:

Environmentally friendly – Using vegetable oil as chain lubricant poses no threat to the environment.

Effective – Vegetable oils have natural properties including good lubricity, resistance to shear, a high flash point, and a high viscosity index. These qualities lend themselves to chain lubricant requirements similar to petroleum-based chain oils, and do not contribute to chain or bar wear over time.

Safer for the user – Chain saws run at high RPMs which result in oil misting. This can affect the user through inhalation and or dermal absorption. Canola-based chain oils have low vapor pressure, which reduces inhalation of fumes by users. In this regard, studies have shown vegetable oils to be safer than petroleum based oils.

Cheaper – A 4 liter jug of chain oil costs $12.99 ($3.24/liter) at my local big box home supply store, while a 3 liter jug of canola oil costs $7.99 ($2.66/liter).

Readily available – Canola oil is a renewable, sustainable farm product. It is readily available at most grocery stores.

Tips for replacing chain oil with vegetable oil:

Use canola oil – Canola oil is currently the most common environmentally compatible chain-and-bar lubricant. Canola-based chain and bar oil has been extensively tested in Europe. Manufacturers and some users claim that there is a potential for extended bar-and-chain life when using canola-based products because it lubricates and adheres to metal better than petroleum-based oils.

Vegetable oil is thinner – Vegetable oils have lower viscosities than the bar/chain lubricants and therefore flow more readily. First time users of vegetable oil for chain lubricant may notice some leaking (while the saw is not running) from the oil port on the bar, near where the bar is bolted to the saw. To test for leaking, set your saw on a cardboard scrap overnight and see if there is spotting in the morning. If so, you can adjust the oiler flow screw usually located at the base of the saw. For long term storage, leave oil reservoir empty.

Check fluid levels when finishing first tank – Chain saws have two reservoirs, one for the “Mix” (gas and two-stroke oil combined) and one for the “Oil” (chain oil/ bar lubricant). These tanks are designed to run out at the same time, since running a saw with the oil reservoir empty may damage the chain and bar. If you are using vegetable oil for the first time, fill both reservoirs to the top (using vegetable oil in the “Oil” reservoir and gas/2-stroke mix oil in the “Mix” reservoir) and then check the fluid levels when you are getting low on gas. The levels should be about the same – both tanks should run out at the same time. If not, adjust your oil flow screw.

Vegetable oil is harder to see – The first time I used vegetable oil in my chain saw, I had an accidental overflow – the oil was so clear I didn’t notice it filling towards the top of the reservoir. When filling your saw with vegetable oil, get used to looking more carefully to gauge the fill level.

Cold temperature limitations – The cold-temperature properties and oxidation stability of vegetable oils are their main disadvantages compared to petroleum-based oil, and additives are needed to overcome these problems. Tests have shown that canola-based chain oils provide good performance down to -13 degrees F but storage can affect the pour point temperature (they may not pour easily after standing for several days at -22 degrees F). If you operate a chain saw in climates this cold, you may want to consider vegetable-based chain oils “with additives” which are becoming available in stores which sell chain saw accessories.

The Forest Engineering Research Institute of Canada (FERIC) tested and reported on field trials of a vegetable-based oil for lubricating chain saws. (See FERIC General Field Note Number 35.) The overall results were positive. Users reported that the vegetable-based oil was easier to clean from clothes and equipment. Users also experienced less skin irritation.

Although using vegetable oil to replace petroleum-based chain oil is a step forward from an environmental perspective, operating a chain saw still emits fumes from the 2-stroke gas mix. When using a chain saw, try to plan your cuts in advance to be most efficient, and never set down a running saw. Operators and nearby workers should use “ear muff” hearing protectors and respirators capable of handling the chainsaws emissions.

One final note: This article recommends using vegetable oil to replace chain oil in chainsaws. However, this does NOT mean replacing “mix” oil which is used for the gas mix. For mix oil, you must use the petroleum-based 2-stroke mix oil recommended by the chain saw manufacturer.

Reference
Vegetable Oil for Lubricating Chain Saws