Smoke coming from your sign is most likely a problem that can damage the bar and chain or engine if the problem isn’t found and fixed.
A Craftsman chainsaw is smoking due to increased friction between the bar and chain, too much oil in the fuel mixture, water in the fuel system, or a plugged air filter.
Reasons a Craftsman Chainsaw is Smoking:
- Dull or incorrectly sharpened chain
- The chain is too tight
- An empty tank of bar and chain oil
- The wrong type of bar and chain oil
- Clogged oiler
- Plugged air filter
- Too much oil in the fuel mixture
- Water in the fuel mixture
Take caution when troubleshooting and repairing your chainsaw. Shut off the chainsaw, wait for the engine to cool, and remove the spark plug boot.
This post may include affiliate links. Purchases made through these links may provide a commission for us, at no extra cost to you. As an Amazon Associate, we earn from qualifying purchases.
Follow all safety instructions provided in your equipment operator’s manual before diagnosing, repairing, or operating. Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.
Craftsman Chainsaw is Smoking from the Bar & Chain While Cutting
When your Craftsman chainsaw smokes when cutting, you need to look for items that can cause increased friction between the bar and chain.
This may be due to a dull chain, poor lubrication, or a chain that won’t move freely around the bar.
Dull Chain or Incorrectly Sharpened Chain
A dull chain will cause your Craftsman chainsaw to smoke. This is because a dull chain or a chain that isn’t sharpened correctly will cause you to have to apply more pressure to cut wood.
This pressure causes metal-on-metal friction from the bar and chain creating heat and smoke.
Look for these signs indicating the chain is dull:
- Needing to apply increased pressure on the bar to make a cut.
- Fine sawdust is created when making a cut.
- Chips or damage to the chain.
- Worn teeth and rakers.
You can sharpen the chains yourself. If you don’t have experience sharpening chains, I highly recommend having a professional sharpen them for you. A chain that isn’t sharpened right can be a serious safety hazard.
Lack of Bar & Chain Oil
Oil is required to keep the chain moving smoothly around the bar to avoid friction buildup. A lack of oil can occur when you run out of bar and chain oil in the tank or you have a clogged oiler.
Fill the bar and chain oil tank if it is low on oil or empty.
To check for sufficient oil on the bar, run your chainsaw at about 1/2-3/4 throttle. What you are looking for is a line of oil coming off the bar while holding it less than a foot off the ground.
If you aren’t getting good lubrication, make sure the bar is in good condition and the oil channel isn’t blocked. Replace a worn or damaged guide bar and clean the oil channel if needed.
It is good to get into the habit of refilling the bar and chain oil everything you fill your Craftsman with fuel. However, if the oil you are running in the saw is too thin, you may go through oil at a faster rate and have to check and refill it more often.
Wrong Type of Bar and Chain Oil
Using a bar and chain oil that is too thin may cause bar and chain damage and increased friction causing smoke coming from the bar. An oil that is too thin may not stick to the bar and chain and instead get slung off of it.
Chain is Too Tight
The chain will loosen as you use it so you’ll need to check it regularly and tighten it. However, if you tighten the chain too much, it will not move freely around the bar and increased friction will result in smoke.
Adjust the chain tension on a Craftsman chainsaw:
- Remove the spark plug wire.
- Unlock the chain brake.
- Loosen the bar retaining nuts that hold on the cover over the clutch and chain brake.
- Hold the nose of the bar up.
- Turn the tensioning screw counter-clockwise to loosen the chain and clockwise to tighten the chain.
- Once you achieve the correct tension, tighten the bar retaining nuts while continuing to hold the bar nose up.
You want the chain to sit securely around the bar, but still able to move easily. You don’t want it too loose that it hangs from the guide bar.
Craftsman Chainsaw is Smoking from the Exhaust
When your Craftsman chainsaw smokes while running, you will need to look at airflow issues including a plugged air filter or a problem with the fuel mixture.
Clogged Air Filter
Operating a chainsaw is a dirty job. Sawdust and small wood chips are tossed into the air.
An air filter is used on your chainsaw to ensure the engine receives clean air. The filter keeps dirt and sawdust from entering the air intake and wearing on the engine.
If you use your chainsaw sparingly, replace your air filter annually and check it before each use. If you use the saw regularly, check the filter frequently and replace it when it becomes very dirty or damaged.
If you don’t regularly check and clean the filter to ensure it is in good condition, the buildup of dirt and sawdust can clog the filter and not allow sufficient air to pass through the filter.
The fuel mixture will run rich and smoke. The engine may eventually overheat and shut down due to a lack of air.
Too Much Oil in the Fuel Mixture
Oil added to the fuel for a Craftsman chainsaw adds the lubrication the engine needs to keep running. Craftsman chainsaws require gas and oil mixed at a ratio of 40:1. Using more oil than this can cause the engine to begin smoking.
Once you realize the smoke is coming from the wrong fuel mixture, remove the fuel and fill it with fresh fuel with the correct gas-to-oil mix.
This won’t normally cause long-term damage. However, running fuel with too much oil may cause running problems due to an increased buildup of carbon in the exhaust system.
Refer to this article for more information on choosing the right fuel for your Craftsman chainsaw.
Water in the Fuel System
Water in the fuel mix can cause white exhaust smoke. Water is corrosive to the fuel system and engine.
You may be looking for a way to remove water from the fuel, but you should empty the fuel tank and refill it with fresh gasoline and 2-cycle engine oil mix.
Trying to save a little money to remove water isn’t worth the potential damage requiring a large repair bill or chainsaw replacement.
Mix in a fuel additive like Sea Foam Motor Treatment with the fuel mixture to help remove moisture and clean the fuel system. Start the saw and allow it to run to get the treated fuel through the system.