Chainsaws are essential tools for various tasks, including tree felling, pruning, and firewood cutting. However, one common issue that chainsaw users face is oil leakage. This can be a nuisance and can also lead to safety hazards if the oil drips onto the user or the work surface. Understanding the causes of chainsaw oil leaks can help users take steps to prevent or minimize them.
Key Facts
- Oil Tank Vent: One common cause of chainsaw oil leaks is a clogged or malfunctioning oil tank vent. If the vent is unable to equalize pressure, it can lead to leaks. For example, if you work outdoors in the cold and store your chainsaw indoors where it’s warm, the pressure build-up inside the oil tank may push oil out.
- Oil System Operation: Chainsaws have an oil tank that stores bar and chain oil. The oil is pumped from the tank to the guide bar through a valve or breather that maintains a slightly positive pressure in the oil tank. This ensures oil delivery to the bar and chain when they are in use. However, when the chainsaw is not in use, oil can slowly form larger droplets that may drip onto the surface below.
- Chain Rotation: When the chainsaw is in use, the rotating chain flings some oil from the chain onto the body of the saw. Additionally, as the chain passes around the guide bar and sprocket, some oil is also flung from the chain. Most of the oil is absorbed by the log and sawdust produced by the chain, leaving little to drip onto the surface under the saw.
- Temperature Variations: Changes in temperature can also contribute to oil leaks. In areas with drastic day/night temperature changes, the air and oil in the tank can contract overnight and expand during the day. This can cause the oil to be forced out through the oil pump ports, leading to leaks. Extreme temperature variations can even result in the tank pumping itself dry.
To address the issue of oil leaks, you can take the following steps:
- Check the oil tank vent to ensure it is not clogged or malfunctioning.
- Follow the instructions in the chainsaw’s operator manual to verify that the oil system is working properly.
- Clean any oil residue from the saw body, paying attention to recesses that can retain oil.
- Place a sheet of cardboard under the saw and observe if there are any oil stains or pools after a period of time.
- If storing the chainsaw, consider draining the bar oil and fuel mix or lay the chainsaw on its side with the oil cap slightly open to reduce pressure build-up.
Oil Tank Vent Issues
One of the primary causes of chainsaw oil leaks is a clogged or malfunctioning oil tank vent. The oil tank vent is a small opening that allows air to enter the tank as oil is pumped out. If the vent is blocked, it can create a vacuum inside the tank, causing oil to leak from other openings. This is particularly common when the chainsaw is stored in a warm environment after being used in a cold environment. The warm temperature causes the air in the tank to expand, increasing the pressure and forcing oil out through the vent or other openings.
Oil System Operation
Chainsaws have an oil system that stores bar and chain oil in a tank. The oil is pumped from the tank to the guide bar through a valve or breather that maintains a slightly positive pressure in the oil tank. This ensures oil delivery to the bar and chain when they are in use. However, when the chainsaw is not in use, oil can slowly form larger droplets that may drip onto the surface below.
Chain Rotation
When the chainsaw is in use, the rotating chain flings some oil from the chain onto the body of the saw. Additionally, as the chain passes around the guide bar and sprocket, some oil is also flung from the chain. Most of the oil is absorbed by the log and sawdust produced by the chain, leaving little to drip onto the surface under the saw.
Temperature Variations
Changes in temperature can also contribute to oil leaks. In areas with drastic day/night temperature changes, the air and oil in the tank can contract overnight and expand during the day. This can cause the oil to be forced out through the oil pump ports, leading to leaks. Extreme temperature variations can even result in the tank pumping itself dry.
Preventing Chainsaw Oil Leaks
To address the issue of oil leaks, you can take the following steps:
- Check the oil tank vent to ensure it is not clogged or malfunctioning.
- Follow the instructions in the chainsaw’s operator manual to verify that the oil system is working properly.
- Clean any oil residue from the saw body, paying attention to recesses that can retain oil.
- Place a sheet of cardboard under the saw and observe if there are any oil stains or pools after a period of time.
- If storing the chainsaw, consider draining the bar oil and fuel mix or lay the chainsaw on its side with the oil cap slightly open to reduce pressure build-up.
By following these steps, you can minimize the risk of oil leaks from your chainsaw, ensuring a safe and efficient operation.
References
- “Why Do Chainsaws Leak Bar Oil?” STIHL Australia. https://www.stihl.com.au/chainsawleak.aspx.
- “Most Common Causes for a Chainsaw to Leak Bar and Chain Oil.” Husqvarna Australia. https://www.husqvarna.com/au/learn-and-discover/most-common-causes-for-a-chainsaw-to-leak-bar-and-chain-oil/.
- “Chainsaw Storage (Leaky Bar Oil).” ArboristSite.com. https://www.arboristsite.com/threads/chainsaw-storage-leaky-bar-oil.357559/.
FAQs
Why does my chainsaw leak oil when it’s not in use?
Chainsaws may leak oil when not in use due to several reasons. One common cause is a clogged or malfunctioning oil tank vent. When the vent is blocked, it can create a vacuum inside the tank, causing oil to leak from other openings. Additionally, temperature variations can also contribute to leaks. In areas with drastic day/night temperature changes, the air and oil in the tank can contract and expand, forcing oil out through the oil pump ports.
What is the purpose of the oil tank vent on a chainsaw?
The oil tank vent on a chainsaw is a small opening that allows air to enter the tank as oil is pumped out. This helps to maintain a slightly positive pressure in the oil tank, ensuring a steady flow of oil to the bar and chain when the saw is in use.
How can I prevent oil leaks from my chainsaw?
To prevent oil leaks from your chainsaw, you can take several steps. First, check the oil tank vent to ensure it is not clogged or malfunctioning. You should also clean any oil residue from the saw body, paying attention to recesses that can retain oil. Additionally, consider draining the bar oil and fuel mix if you are storing the chainsaw for an extended period.
What should I do if my chainsaw is leaking oil?
If your chainsaw is leaking oil, you should first identify the source of the leak. Check the oil tank vent, oil lines, and seals for any damage or blockages. Once you have identified the source of the leak, you can take steps to repair or replace the faulty component.
Can I use any type of oil in my chainsaw?
No, you should only use oil specifically designed for chainsaws. Chainsaw oil is formulated to withstand the high temperatures and stresses of chainsaw operation. Using other types of oil, such as motor oil, can damage your chainsaw and void your warranty.
How often should I check the oil level in my chainsaw?
You should check the oil level in your chainsaw before each use. The oil level should be at or slightly below the “full” mark on the oil tank. If the oil level is low, add enough oil to bring it up to the proper level.
What are the signs of a faulty oil pump in a chainsaw?
Signs of a faulty oil pump in a chainsaw may include a decrease in the amount of oil being delivered to the bar and chain, an increase in oil leakage, or a burning smell coming from the saw. If you suspect that your chainsaw’s oil pump is faulty, you should take it to a qualified repair technician for diagnosis and repair.
How can I extend the life of my chainsaw’s oil pump?
To extend the life of your chainsaw’s oil pump, you should use high-quality chainsaw oil, keep the saw clean and free of debris, and avoid running the saw at high speeds for extended periods. Additionally, you should have your chainsaw serviced regularly by a qualified technician.