Can Engine Oil be Used to Preserve Wooden Fences?

by Product Review Lad | Last Updated: May 21, 2021

Putting up a new wooden fence? You are going to need to treat it to prevent premature damage. When people want to protect their wooden fences, it is usually from the elements and pests. If you are looking for a way to protect your fence for years to come and stain them at the same time, there are a couple of alternatives. One you may have heard about is used engine oil.

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Can Engine Oil be Used to Preserve Wooden Fences?

Can You Use Used Engine Oil to Preserve Wooden Fences?

The short answer is yes. Old engine oil can be used as a stain and preservative on wood. Some people will use a mixture of motor oil and diesel fuel or creosote as a wooden fence protectant.

But how did this practice come around? During the early and mid-1900s, farmers would use whatever they had to get by. Sometimes, they would reuse engine oil from their equipment to protect their wooden barns and fences. The oil stopped insects, like termites and boring bees, from damaging the wood, too.

Does Motor Oil Rot Wood?

No, used oil doesn’t rot the wood. The oil soaks into the wood pores, reinforcing the material and halting the absorption of moisture.

Going back to those 20th-century farmers, when they used motor oil on wooden fence posts, they found that the oil deterred decomposition. Plus, the fencing would last much longer than average and gained a pretty golden sheen that didn’t fade. Sounds pretty good, right?

The Drawbacks of Used Engine Oil on Wood

As with anything, there are some disadvantages to choosing motor oil over natural alternatives, like linseed oil or stains.

The first negative is the smell. Whether you do a 50/50 oil and diesel mixture or go with straight used motor oil, the wood is going to stink for a long while—maybe forever.

Second, toxicity. Oil never dries or cures. It remains oily forever, and even if it sinks into the wood, it can be removed. When it rains, some oil will seep from the fencing into the ground, leaving a bare patch in the lawn where the ground has been contaminated. If you plan on using engine oil on wood, be sure to get the appropriate equipment, like a face mask, gloves, and construction-grade work pants.

Third, in a hotter, drier environment, used engine oil could be a humongous risk. In humid climates, oil-stained fences and barns are less likely to catch fire, because the wood would never dry. However, oil and wood in an arid climate are asking for trouble. Additionally, the heat could cause the used motor oil to release toxins into the air.

Wrapping up

Yes, you can use used oil to preserve wooden fences, but it may not be the best option out there. Used motor oil looks nice and protects wood well, yet it will stink and can be toxic to the environment.