How to Start a Flooded Chainsaw – The Ultimate Guide

If you want to learn how to start a flooded chainsaw, don’t worry; you’re not alone. A flooded chainsaw is a common issue that can be easily fixed.

In fact, anyone who uses dirt bikes, cars, or any machine that has a carburetor may have experienced a flooded chainsaw engine.

In this article, we will go through how to start a flooded chainsaw. Before we get started, let’s look at the signs and causes of flooded chainsaws.

To start a flooded chainsaw, make sure the chainsaw is turned off and the choke is set to the run position. Next, remove the spark plug and clean it with a soft cloth. Then, pull the starter cord a few times to clear out any excess fuel.

Finally, reinstall the spark plug and try starting the chainsaw again. If it still won’t start, wait 15 minutes before trying again. With these steps, you’ll be back to your outdoor projects in no time.

Flooded chainsaw signs

The signs of a flooded chainsaw include the scent of gas in the muffler and the engine being challenging to start.

Engine flooding occurs because of incorrect air and fuel mixture, worn spark plugs, or clogged air filters. To avoid flooding, it is important to make sure that you’re using the correct fuel mixture.

What causes the flooding of a chainsaw?

A flooded chainsaw is caused by various factors, such as the carburetor being clogged, a dirty spark plug, insufficient air intake, and an incorrect fuel mixture. Here are the steps to starting a flooded chainsaw.

1. Clogged/Blocked Air Filter

How to Start a Flooded Chainsaw

If the air filter is blocked, it is important to replace it with a new one before starting the chainsaw.

It is also essential that you clean the air filter regularly to prevent flooding. The problem is that there’s too little air coming in and too much fuel, which can lead to flooding.

The amount of fuel compared to the air going to the piston is too high, resulting in liquid gasoline being compressed.

This will wet the spark plug and prevent it from firing, ultimately leading to flooding. If this problem occurs, it’s important to replace the air filter and make sure it is regularly cleaned.

2. Choke

How to Start a Flooded Chainsaw

If the chainsaw choke starts or closes too many times during operation, it can cause flooding because less air will be able to come through.

It is also important to make sure that the chainsaw choke isn’t stuck on. If it is, then you need to open it up again to allow more air into the engine.

3. Fuel Mixture Screw

How to Start a Flooded Chainsaw

The third point to check is the fuel/air mixture settings. If the mix screw is screwed too far out, it will allow too much fuel to come down and out into the inlet, even though there’s enough air coming through.

Regardless of this, if there’s too much excess fuel allowed through, then we’re going to get the same problem—flooding.

Therefore, it’s important to check the fuel/air mixture screw setting and make sure that it is adjusted correctly. ‘

4. Spark Plug

How to Start a Flooded Chainsaw

If the chainsaw’s spark plug is getting old or there’s a problem with the spark where it’s not sparking quite right, combustion cannot take place properly, and eventually, even though there is air coming in with the fuel, a buildup of fuel will occur.

As a result, the fuel will become more of a liquid in there, rather than being atomized. This can cause flooding and is the same if the spark plug isn’t sparking at all when trying to start an engine.

Therefore, it’s important to check the spark plug to make sure that it is firing correctly or replace it with a good spark plug with the help of a spark plug wrench.

How To Unflood A Chainsaw So It Will Start

1. Let The Fuel Evaporate

How to Start a Flooded Chainsaw

The first way to start a flooded chainsaw is to let the excessive fuel evaporate and dissipate out of the engine.

To do this, simply let the chainsaw sit idle for 20 minutes and then try to start it. Sometimes, you need to let the chainsaw sit idle for days before it will start up.

If this doesn’t work, move on to the next step. When you’re ready to start the engine, keep in mind not to open or activate the choke.

2. Starting A Flooded Engine With No Tools

If you don’t have any tools available, then you can also try starting the flooded engine by rapidly pulling the starter rope. This will help clear out the excess fuel.

Engage the chain brake in the run position, not the choke position, and hold the trigger wide open, holding it down with your hand firmly on the ground, before trying this method.

While fully depressing the throttle lever, pull the starter rope rapidly for around 20 minutes until the saw starts. If it still doesn’t start, move on to the next step.

3. Starting A Flooded Engine By Removing The Spark Plug

How to Start a Flooded Chainsaw

Another way to start a flooded-engine chainsaw is to remove the spark plug with a wrench. Remove the rubber boot from the spark plug, unscrew it with an adjustable wrench, and pull it out.

Don’t reinstall the spark plug rubber boot, as it can spark and ignite the gas inside the saw. Place the spark plug away from the chainsaw, turn your saw upside down, and gently pull the starting rope.

This will push out some of the excess fuel. Pull the starter cord 4 or 5 times, each time more, and excess gas will be pushed out.

As the engine was flooded, the spark plug will have some gas on it which needs to be wiped off with a dry cloth before reinstalling. Reinstall the spark plug and boot, put the choke in the off position, and start the engine.

Steve’s Small Engine Saloon

How to Start a Flooded Chainsaw FAQs

How long does it take a flooded chainsaw to start?

A flooded chainsaw could take anywhere from a few minutes to several days to start. It depends on the severity of the flooding, how long it’s been sitting, and the condition of your spark plug.

You may need to let it sit for a few hours or days before attempting to start it, or you can use one of the techniques such as removing excessive gas or cleaning spark plugs and air filters.

How do you know if a chainsaw is flooded?

A flooded chainsaw will be hard to start. It may also have smelled of fresh petrol near the muffler. Chainsaw flooding occurs due to an excess of fuel in the fuel mixture, a stuck open choke, a spark plug that is not firing correctly, or a clogged carburetor.

Final Thoughts

Starting a flooded chainsaw can be tricky, but it can be done with the right skills and technique.

By following these tips and techniques for “how to start a flooded chainsaw,” you can be sure your chainsaw will start running again in no time.

Always check the fuel, spark plug, and air filter settings before starting your chainsaw, as well as make sure it is adjusted correctly.

A flooded engine occurs due to excess fuel in the fuel mixture, a choked spark plug that is not firing correctly, or a clogged air filter.

If you know these few simple steps, starting your chainsaw will be much easier, even when it is flooded.

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Charlie Bass

Charlie has been a mechanic for over 25 years and has worked on everything from small engine gardening equipment to huge diesel-electric mining haul trucks, trains and even aircraft. This broad range of industry experience gives him a unique insight into almost anything mechanical especially with an engine, including gardening and landscaping equipment. He currently owns his own mobile mechanic business and lives with his family in Australia.

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