Why does chainsaw smoke when cutting wood?

We easily forget all the heavy work we do with our chainsaws. All the ripping and cutting can have a great impact on our chainsaw, even the best of them.

Your chainsaw may develop some fault or that might cause the release of smoke from its parts on regular use. This situation can slow down your chainsaw performance, efficiency and speed. This will also reduce the quality of finished products made due to bad cutting.

When your chain saw suddenly develops this fault, it can be confusing, especially when you are not sure whether it is normal for chain saws to smoke.

By the end of this blog post, you will understand why your chain saw suddenly starts releasing smoke and how you can resolve this.

Why Does My Chainsaw Smoke When Cutting?

When you notice smoking while cutting with your chain saw, it is crucial to look out for some possible causes. Your chainsaw can smoke when cutting due to a variety of reasons. The smoke can be a sign of overheating, too much oil in the fuel mix, a blunt saw blade or poor lubrication. 

When you notice smoke coming out from any of your chain saw parts. Try finding out the cause of the smoke by checking where the smoke comes from. The source of the smoke determines the best way to solve the problem.

Chainsaw’s Chain

When your chainsaw releases smoke from the chain, it is a sign that it is generating too much friction when wood cutting. This usually starts after cutting for a while. 

The excess heat generated might burn the sawdust causing the chainsaw to smoke,  or in the case of wet woods, it could be from the water evaporating from the wood.

Exhaust Port

When the chainsaw exhaust emits black smoke, it’s usually because the chainsaw mix has too much oil in it. Most chain saw manufacturers employ the 1.50 oil/fuel mix ratio.

You are bound to face some chainsaw smoking problems if your oil-fuel ratio is not well balanced according to the measurement specified by your manufacturer. 

To fix this, you should drain your fuel tank and refill with the correct mix.

A man working with a lumberjack

Engine

In the case of a smoking engine, you could be facing an air filter or cooling system issue. It could also be a result of an unbalanced oil-gas ratio. 

Expect that the air filter gets blocked with dust over time due to the working condition of chainsaws.

The air filter is responsible for protecting the chainsaw engine from dust and for cooling the engine. When the air filter becomes blocked, it can lead to overheating and, eventually, engine smoking.

If the damage is too bad, you might need to remove the filter entirely and replace it with a new one.

Otherwise, you can simply remove the dust blocking it by knocking it off with your hand or brushing it off with a brush. 

The motor of an Electric Chainsaw

When using an electric chain saw, the motor is likely to face more resistance as a result of a dull blade or bad oil. 

A dull blade causes increased motor power which causes the motor itself to smoke. An overworked motor generates smoke during cutting and eventually gets worn out.

Lumber cutting with a chain. saw 

What To Do When ChainSaw Engine is Smoking and Overheating 

When the smoking comes from the engine of your chain saw, it could be a result of an unbalanced oil-to-gas ratio or a problem with the air filter and engine cooling system.

Exhaust Smoke Due to Wrong Fuel-to-oil Ratio 

When the chain saw exhaust emits black smoke, it’s usually because the fuel mix has too much oil in it. 

Most chainsaw manufacturers employ the 1.50 oil/fuel mix ratio. An unbalanced oil-fuel ratio causes chainsaw problems like exhaust smoking. 

 To resolve this, you should drain the fuel tank and refuel with the correct oil mix. 

The Chainsaw Air filter is Blocked or Clogged

The chain saw air filter gets clogged up with dust over time due to the dusty working environment.

The air filter is responsible for protecting the engine from dust and for cooling the engine.

When the air filter becomes clogged, it can lead to overheating and, eventually, engine smoking. 

If the damage is too bad, you might need to remove the filter entirely and replace it with a new one.

Otherwise, simply dust-blocking it by knocking it off with a hand or brushing it off with a brush, or better still, blowing the dust off with compressed air. 

A chainsaw at work 

How to Tell When Your Chain Needs to be Sharpened 

Here are some signs that your chain saw is due for sharpening.

Bad Cuts

Under normal conditions, making precise cuts with a chainsaw doesn’t require any extra effort.

However, with a full blade, you will need to add additional force to get it to cut through the wood. 

The difficulty and extra time taken to cut through a particular section of the wood causes the saw to make bad cuts on wood.

Experiencing difficulty in cutting your wood or cutting a piece of wood in a longer time than usual is a sign that your saw blade needs sharpening or replacement.

Bouncing Blade

A dull blade will cause kickbacks to the chain during cutting. Since the blade is not sharp enough, it may not easily cut through the wood. 

The blade might stick into the wood, causing a kickback/bounceback. This is a clear sign that your saw needs immediate sharpening.

Smoke

A dull blade increases the cutting time for any piece of wood. It also the level of friction opposing the saw.

 With increased cutting time and friction, the engine generates more heat which may cause smoking from the chain blade.

Sawdust

You can determine the condition of your saw blade by observing the size of the sawdust generated during cutting.

 If the scraps are larger, it means that your blade is still sharp enough. But a dull blade will only produce wood dust.

As a way of fixing this problem, sharpen your saw blade using a chainsaw sharpener. 

Conclusion

Hopefully, at this point, you must have figured out what the problem with your chainsaw is. 

Always remember to check for the source of the smoke before making a conclusion.

 If you follow the directions given in this article, you should be able to fix your chainsaw problem without much expense.

As a way of maintenance, always check the lubrication, sharpen your saw blade even before it gets blunt and ensure to use the correct oil-gas ratio (usually 1.50 oil/gas) when topping up your fuel tank.