Chainsaw Leaking Bar Oil – Reasons & Solutions in 2023

Do you have a chainsaw leaking bar oil? This is among the most common problems faced by chainsaw owners – however, if this problem continues over a prolonged period of time, it is certain to inflict an adverse impact on the performance of your chainsaw.

Proper and timely lubrication of the chainsaw bar and chain is an inevitable part of the chainsaw’s maintenance process. Having a chainsaw that leaves a spot of oil at its storage place is something that might occur due to some serious problem – and if this is happening for a long period, this is a time to show your concern.

Usually, the leakage of oil from the chainsaw doesn’t exceed the limit of 10ml per day – if the leakage is of some bigger intensity, it can be a warning sign of some serious technical fault. Therefore, considering the need of the hour, I will try to explain the causes behind the leaking of bar oil and how this problem could be fixed.

Chainsaw Leaking Bar Oil

Leaking of Bar Oil from Chainsaw?

Leaking of oil from chainsaw doesn’t only create mess; instead, it massively degrades the chainsaw’s efficiency in terms of performance. Let us analyze some of the common and rare facts that could cause the leakage of oil from your chainsaw;

1. Poor Ventilation of the Oil Tank 

This is a common problem caused by a vacuum created in the oil tank due to a poor ventilation system. Technically, there should be equalized air pressure inside and outside the tank – when there comes a gap in the readings, the dripping of oil appears to be a necessary phenomenon.

Commonly, most of the tanks comprise tanks that have a one-sided valve to equalize the pressure of air; but this one-sided valve fails to deliver the job when the temperature fluctuates. For instance, when the temperature of the surroundings falls, the valve allows air enters the valve and normalizes the pressure, but when the temperature rises, the valve fails to maintain the pressure because of being functional for one side.

This problem is more frequent in an area where temperature fluctuation is more. However, it isn’t a big problem, and it can be fixed using the following method;


The best and easiest solution to this problem is to loosen the cap of the oil reservoir to equalize the pressure of the air inside and out of the tank. Once the pressure is equal inside and outside the tank, no oil will be forced to flow out of the tank. Do not forget to tighten the reservoir cap after you have equalized the pressure of air.

2. Overfilled Oil 

Overfilling of oil is one of the most common and obvious problems. When the tank is overfilled, the oil is certain to seep into the ports and sprocket showing leaking from the bar or chain.

Usually, this problem is more frequent in areas where fluctuation in temperature is more common – the oil tank is already filled, and when the temperature increases, there creates excitement in between the molecules of fuel colliding with each other; it causes the expansion of fuel.


There is nothing technical in this; you only need to make sure that the oil isn’t overfilled. However, be more cautious when you are living in an area that experiences abrupt fluctuations in temperature.

3. Missing of Stud

Again, a missing stud is among the repeated causes of chainsaw leaking bar oil and chain oil. The stud is openly visible at the bottom of the tank from the muffler’s side. Due to being small in size, it is likely to get this misplaced, and cause leakage of oil.

If you come across a leakage of oil from your chainsaw, do not forget to check if the stud is in its place or not.


Without losing any technical conditions, you can simply attach a new stud to avoid leakage. However, be sure that you get the same stud that matches the dimensional requirements of the hole. Once the stud is back in its place, it is likely to stop the leakage.

4. Leakage in Oil Line 

This is the least common factor that contributes to the leakage of oil from the chainsaw. Oil lines are responsible to transport oil from the tank to the oil pump. Any of these oil lines may get punctured at any time causing the spilling of oil.

To make sure if the leakage is happening from the oil line or not, remove the lower cover, and tilt it to check if the line is faulty.


The only solution to solve this problem is to replace the ruptured oil line with a new one. Make the oil tank empty, get the ruptured oil line out, and install a new one in its place.

So, these are some problems that contribute to chainsaw leaking bar oil. Apply the aforementioned solutions in accordance with their relevant problems – it is necessary to have a chainsaw that could serve you longer and better.

Other than this, chainsaw leaking bar oil or chain oil is somehow relevant to its storing position. So, let’s see that how to store chainsaws without oil leaking.

How To Store Chainsaw Without Oil Leaking?

Why does a chainsaw leak bar oil when stored? It isn’t always necessary that the chainsaw leaking bar oil is due to some technical fault – it could also be a problem related to the storing position and circumstances of the chainsaw.

Having explained all possible causes and their solutions, the followings are some common storing approaches that can further eliminate the risk of leakage of oil from your chainsaw;

1. Check the Tank Before Storing 

Once you have done with using your chainsaw, and now you are to store it unless you need it again, make sure that the level of fuel in the oil tank isn’t inappropriate. An overfilled tank is more likely to show leakage due to fluctuations in environmental temperature.

Meanwhile, the best option is to store your chainsaw without fuel in the tank. It also saves your chainsaw from scaling carbon particles on the walls of the carburetor.

2. Check the Inner Body of the Chainsaw Before Storing 

It is a common mistake committed by most chainsaw users – they store their chainsaws right away after using them without checking the inner body of the chainsaw. Checking the inner body of the chainsaw makes you sure about any leakage from the oil tank or oil line. Meanwhile, you also get the chance to clean any kind of debris attached to the inner body of the chainsaw.

3. Detach the Spark Plug 

Although this is a minor safety precaution; however, it may save you from being worried at the time when you need your chainsaw in an emergency. If you are storing your chainsaw without knowing when you need it again, it is recommended to detach the spark plug; otherwise, it may deteriorate with time.

4. Vertical Storage of Chainsaw

Can I store the chainsaw vertically? Yes, you can store your chainsaw vertically – but with few safety precautions necessary to avoid leakage of oil. First of all, it is recommended to hang your chainsaw vertically only when you have made the fuel tank empty.

Secondly, if you keep some fuel in the tank, you must return after 2 to 3 days, and loosen the oil tank’s cap to evacuate the built vacuum of air inside the tank.

5. Don’t Store on Either Side 

Usually, the opening cap of the oil and fuel tank is present on the left side in most of the models of chainsaws – while on the other side, there is a hole that allows oil to seep into the bar and chain. So, it is possible for oil or fuel to leak out if stored on either side of the chainsaw.

Therefore, by complying with the aforementioned instructions, leakage can be eliminated. Most preferably, it is suggested to make the oil tank empty before the chainsaw is stored.

Final Words

If you have a chainsaw leaking bar oil, this is the time to get rid of this problem; otherwise, it will surely create a great mess and reduce the performance of your chainsaw. I have described a few simple steps along with their solutions in the aforementioned paragraphs – by complying with the given instructions, you can easily avoid leakage problems.

Along with this, I have also tried my level best to make it easy to understand how to store chainsaws without leakage. If you have any questions related to the topic, you can ask me.

Frequently Asked Questions (FAQs)

Q1. Why does my chainsaw leak bar oil?

The leakage of oil from the bar of your chainsaw can be a usual phenomenon; there are very common reasons which might be responsible for leaking of oil from the bar of your chainsaw. Followings are the main reasons;

  • Overfilling of oil
  • Missing of stud
  • Leakage in oil line, and
  • Poor ventilation of the oil tank

Q2. How do you stop oil from dripping?

Dripping of oil can be easily avoided by taking care of few things; you need to ensure that the oil tank is not overfilled, stud is present at its place, there is no leakage in oil line and ventilation in oil tank is up to the mark. If all these things are good, you are least likely to face dripping problem.

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