Chainsaws run at high speeds so they can cut through everything they need to, but this also means it may frequently overheat. An overheated chainsaw isn’t as effective and may cause damage to the saw, so you’ll want to prevent overheating as much as possible.
Your chainsaw is overheating because it has a clogged exhaust or air filter, insufficient oil in the fuel mixture, or a dull chain. Overuse could also be the culprit.
In the rest of this article, I’ll discuss the common causes of an overheated chainsaw. I’ll also give you a few simple fixes so you can get back to using your saw as soon as possible.
1. The Exhaust Is Clogged
Many chainsaws have two-stroke engines with exhaust ports, just like cars do (source). If the exhaust gets clogged with dust or other debris, the heat within the chainsaw won’t be able to escape, and the saw will eventually overheat.
Other signs that the exhaust port on your chainsaw is clogged include the following:
- Your saw seems to have less power than usual.
- The saw stalls or fails to start.
- You notice a smokey smell.
- You’re going through fuel more quickly than usual.
- The saw doesn’t sound like it normally does.
How To Fix
You can use a catalytic cleaner to solve this issue. I recommend this Motorkote Cleaner Treatment Fuel (link to Amazon). This formula protects the catalytic system from harmful debris and promotes its efficiency, which helps to increase fuel economy and, if used regularly, it will prevent your chainsaw from overheating over the long term.
2. The Air Filter Is Clogged
Like all engines, chainsaw engines need the right amount of air to ventilate and maintain a safe temperature. Therefore, the engine will likely overheat if the air filter is clogged or blocked with dust and debris from previous use. If left for too long, the air filter may get so clogged that the engine won’t start.
Most chainsaws either have a paper or foam air filter (source). I’ll explain how to clean both types.
How To Fix
To thoroughly clean an air filter, you must remove it first:
- Use a screwdriver to remove the cylinder cover. Most chainsaw air filters are held in place by a metal latch, which you can also use a screwdriver to release.
- One of the most effective ways to clean an air filter is to use an air compressor. I like this PORTER-CABLE Air Compressor (link to Amazon). This air compressor can blow up to 150 psi (1,034.21 kPa), which is way more than you’ll need to clean an air filter. I also like that the motor starts easily in cold weather or with an extension cord.
- Don’t spend too long blowing compressed air into the air filter, as it might not be able to handle the pressure and could break.
- If you have a foam air filter, try washing it in soapy water. You can use a gentle, soft brush to scrub it clean.
- After washing the filter and drying it, I recommend applying some foam filter oil. The Lucas Oil Store Filter Oil (link to Amazon) is a good choice. The low solvent, low viscosity formula is gentle enough that it won’t damage the air filter, but it’ll still improve airflow. The waterproof formula also helps block out water.
Ensure the air filter is completely dry before using it in your chainsaw again, or you risk attracting more debris. Wet filters attract dust and get clogged more easily, which is important to remember if you’ve recently used your saw in rainy or exceptionally humid weather.
If the air filter is dirty and you don’t think you’ll be able to clean it, I suggest replacing the part.
3. There Isn’t Enough Oil in the Fuel Mixture
Chainsaw engines need sufficient lubricant, or else they’ll overheat, so if your engine is overheating, this might be a sign that it isn’t getting enough lubrication. If left unresolved, this can cause serious damage.
How To Fix
To fix this problem, consult your saw’s user manual and see how much oil the manufacturer suggests you use in the fuel mix. Every saw will have different recommendations, so ensure you follow the instructions given.
You can then drain the old fuel mix and replace it.
4. The Chain Is Too Dull
A dull chain requires the engine to work harder than it should to cut through material, so if your chain is old and worn, your chainsaw engine is more likely to overheat. Additionally, you’ll notice the performance of your chainsaw suffers due to a dull chain.
It could also increase the risk of kickback, so this is also a safety concern.
How To Fix
You can sharpen the blades of a dull chain manually or with an electric chainsaw sharpener to make it more effective and prevent the engine from overheating. Whichever method you use, you must wear the necessary safety equipment to protect your hands and eyes as you work.
If the chain is too damaged and has broken teeth, you should replace it instead of attempting to sharpen it. We recommend this AR-PRO 3-Pack Chainsaw Chain (link to Amazon). The pack comes with reliable, durable chains that can safely and effectively cut through even the toughest wood.
The chains are heat-treated and chrome plated, so they’ll maintain their sharpness for longer.
5. You’re Using the Chainsaw for Too Long
Chainsaw engines overheat if the engine runs too long without sufficient lubrication. Most jobs shouldn’t require the engine to be on and running for too long, but if you have a big tree to cut or you’ll be using the saw for an extended period, I suggest taking regular breaks to avoid overheating.
Your chainsaw should get fueled properly to start. So, you should clean the carburetor, check the fuel and air filter regularly, and get the fuel mix ratio right. Click on the link to learn more about the details.
Summary
If your chainsaw overheats occasionally, there’s no reason to worry. However, you want to rectify the issue as soon as possible to improve the performance of your saw. A chainsaw will start to overheat if the exhaust or air filter is clogged, if there isn’t enough oil in the fuel mixture, if the chain is too dull, or if you’ve been using the chainsaw for too long without taking a break.
