Are Chainsaws Supposed to Leak Oil? [Troubleshooting Guide]

One of the most common problems new chainsaw owners face is finding a puddle of oil under their chainsaw after it has been left sitting there for a while. This leads to a lot of confusion as this can happen to new and old chainsaws alike, making it difficult to determine whether the tool if faulty or not.

Are chainsaws supposed to leak oil? To a certain extent, yes. A few drops are normal, as it’s most likely residual oil from the chain. But if there is a huge puddle or if the oil obviously isn’t coming from the chain, then something is out of order and you should investigate further.

First, let’s look at why a “natural” oil leak can occur in the first place. Then, I’ll go into detail about the various other forms of oil leakage, as well as the possible solutions.

Why do chainsaws leak bar oil?

As I’ve mentioned before, a few drops of oil leaking from your chainsaw is normal, as long as its coming from the chain.

While you are using your chainsaw, the oil pump mechanism delivers a steady flow of bar oil to the chain. The chain then spreads this oil around the entire guide bar. After you finish your task, the oil will still be present on the chain and the bar. After a while, it will proceed to form drops and flow down to whatever surface you’re storing your chainsaw on.

This is why finding oil drops under your chainsaw is a normal occurrence. In fact, I have never seen a chainsaw that doesn’t do this.

If this phenomenon bothers you, you can try rubbing the excess oil off your chain with a rug after you’ve finished using your chainsaw. This should prevent most, if not all oil drops from forming.

What to do if your chainsaw is leaking an excessive amount of bar oil

If you find a huge puddle of oil under your chainsaw after letting it rest for a day or so, then something is amiss. This can happen for a number of reasons.

First of all, I’d like to mention that most manufacturers do not recommend storing your chainsaw with the oil tank full. This is because a full oil tank makes leakages more likely to happen.

I’m not saying you should drain the oil from your tank after each usage, but definitely do not refill it before putting away your chainsaw. You should only top it off before using your saw.

Also, most chainsaw nowadays have an adjustable oiler mechanism. This means you can adjust the amount of oil being spilled onto the bar. If your chainsaw is leaking bar oil, you can try turning this to the minimum setting before putting it away.

If you aren’t sure where it is, check your user manual – it can be different for every brand. It usually comes in the form of a small screw on the side of the chainsaw. In many cases this will stop the leakage, or at least reduce it.

It’s also worth mentioning that you should always use proper chain oil for your chainsaw. If yours runs on gas, don’t buy oil made for electric chainsaws as it’s a lot thinner, making a leak all that more likely.

If you did everything right and none of the things mentioned above have helped, it’s possible that the oil tank’s vent is plugged.

The chainsaw’s oil tank vent is plugged

The chainsaw’s oil tank has a small vent that is used to relieve the pressure built up in the tank. If this vent is plugged for whatever reason, the only way for the tank to relieve the pressure is to push oil out of the system.

The vent can be located at a number of places depending on the model, so check your user manual if you aren’t sure where it is. What usually happens is that the vent get plugged by various debris or mud, and you won’t notice it until the bar oil starts spilling out.

If your vent was indeed plugged, make sure to unplug it. After this is done, the oil leak should stop happening.

How to determine where your chainsaw is leaking oil from

In some cases, determining the source of the leakage isn’t all that simple. If the entire chainsaw is sitting in a huge puddle, there is no reliable way to tell where it came from just by looking at it.

When this happens, you should clean up your chainsaw as best as you can. Use a rug to clean up the puddle, then continue removing the oil from the chainsaw. You can remove the guide bar and chain to make sure there is no excess oil left anywhere, but put them back afterwards.

After you are done with this, check if there is any oil left in the tank. If it’s completely empty, fill it to about halfway.

Next, get a piece of cardboard – one big enough so that you can put the chainsaw on it. Put it under your chainsaw, then let it sit for about 24 hours. After you return, you should be able to determine the general area of the leak’s source.

If it’s coming from the chain, you can use the methods I listed above to troubleshoot the problem.

But if it’s coming from the powerhead, you are facing a more serious problem – one that you probably won’t be able to solve at home, unless you are good at repairing stuff.

What to do if the oil is leaking from the powerhead

This rarely happens randomly. More often than not it occurs after you accidentally drop your chainsaw, or hit it to a hard surface by accident. In these cases the oil tank itself can crack, which is really hard to repair unless you can weld it somehow.

If this is not the case, there are a number of things you can look at:

Leaking oil cap

Sometimes, the cap doesn’t seal the tank properly for whatever reason. Maybe it’s old, or maybe the cap is damaged. This is especially troublesome if the oil cap is located on the side of the chainsaw.

The good news is, this can usually be fixed by replacing the oil cap. You can either order one from e-bay, or get it replaced at your local chainsaw service.

Leaking oil line

Sometimes the oil lines themselves can give in due to old age. They are mostly made out of a rubber-like material that is very soft, but its gets harder as it ages. This hardening process can result in cracks appearing on the oil line, causing a leak.

If this is the case, check if you still have your warranty as the oil lines shouldn’t really give in before at least 2-3 years of usage.

This can be fixed by replacing the leaking oil line, but the exact location can be hard to pinpoint if you aren’t sure what to look for.

People also ask

I’m using old motor oil as chain oil, can this cause leakage?
Yes. I have heard of people recycling old motor oil this way, please don’t do it. It has a different composition than normal chain oil, which can result in your “bar oil” leaking. And even if it doesn’t, who knows what it will do to your guide bar and chain.

Peter Toth

Hi! I'm Peter, the owner of BackyardGadget. Working around the house has always been a big part of my life. I've created this site to share my experience, and to help people choose the right tools for the job. Thank you for stopping by!

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