Why Does Your Chainsaw Bogs Down When You Give It a Gas

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Do you own a chainsaw, and you’re noticing that your chainsaw bogs down when you give it gas? If yes, then you are certainly in the right place.

Why does my chainsaw bogs down when I give it gas is a common problem faced by most chainsaw users at some point. There are various reasons why your chainsaw might bog down when you give it gas. Some of the most common reasons are – dirt in the air filters, dirt in the spark arrestors or spark plug, misalignment of the high-speed screw, adjustment of the carburetor, and more. However, don’t worry as there are simple solutions for these issues. 

In this article, you will get to know all about chainsaw bogging down, why does my chainsaw bogs down when I give it gas, solutions for resolving these problems, and more. Continue reading to get all the answers that you are looking for.

Is Chainsaw Bogging Down Normal

Working outdoors can be quite a cathartic experience. However, when your saw bogs down, it can turn an enjoyable day in the backyard into a huge headache. Chainsaw bogging down is an issue that you will eventually face when you’re using a chainsaw. It could quickly throw a knot in the woodworking projects. 

Unless you’re using an electric chainsaw, your chainsaw’s motor will be a combustion system that makes use of a proper ratio of gas, oil, and air. If the chainsaw is bogging down, one of the critical components might not be in its correct balance.

There are numerous issues that could lead to a bogged-down chainsaw, and most of them will have something to do with the combustion engine’s ability to access air or fuel properly. If the chainsaw gets enough of either one of these critical components, it could cause the motor to stall.

Why Does My Chainsaw Bogs Down When You Give It a Gas

1. High-speed screw

When the high-speed screw in your chainsaw carburetor isn’t properly adjusted, or it is open too far, the air will enter the combustion chamber, and only some of it will ignite. Aside from poor cutting performance, not all fuel in the chainsaw will burn. Further, it produces smoke that can fill the air filter and spark plugs, which can cause performance issues.

2. Air circulation

Before you make adjustments to your carburetor’s high-speed screw, which is largely discouraged by most chainsaw manufacturers, you must clean the air filter and spark arrestor.

If any of them are dirty, chances are that they are contributing to the chainsaw stalling, and you should clean them thoroughly.

3. Spark plug

The spark plug tip can be brown like it is supposed to be, so the engine could be getting enough fuel if the spark plug is darker than normal. Further, your engine could be getting too much fuel and the carburetor will require an adjustment.

If you notice that the plug is coated with carbon deposits, then it is a sign that the fuel mixture in the combustion chamber is too rich. If that is the case, you will find excess deposits on the spark arrestor.

4. Carburetor

On most newer chainsaw models, it’ll be difficult to regulate the volume of fuel that the carburetor is passing to the combustion chamber.

If the chainsaw engine stops while idling, the idle adjustment will need to be tightened. If the engine doesn’t bog down until you depress the throttle, you must either tighten the low-speed or high-speed adjustment screw for enhancing its performance.

Solutions for Chainsaw Bogging Down After Giving It a Gas

Bogging down is an issue that can be seen on most chainsaws, and it is largely disliked by everyone. It could easily turn a typical day at work or your projects into a hassle.

In your chainsaw, fuel starvation or termination or connection between the engine and carburetor could lead to a bog down. Aside from these, there are numerous issues that could cause the chainsaw to bog down. However, the solutions to these issues are very simple. Here are the solutions for common reasons why chainsaw bogs down after giving it gas – 

1. Dirt in the air filters

This is one of the biggest culprits when dealing with chainsaw bogging down. The dirt in the air filters can often cause the chainsaw to stall. As a result, the chainsaw will bog down at full throttle. Other than that, the dirt in the filters could reduce the air supply on the carburetor. Hence, the lesser air supply will cause the chainsaw to bog down.

Solution

Fixing or cleaning the dirt from the air filter is a simple task. In fact, if you know the right steps, you can do it in no time. So, let’s see what you should do if you’ve got a dirty filter –

  1. Make use of the user manual for locating the air filter (in most models, it could be located by removing the top cover)
  2. Ensure that you are taking out the spark plug before you remove the filter
  3. Remove the air filter from the housing using a screwdriver 
  4. Wash it with a soft-bristle brush and soapy water 
  5. In case it still isn’t looking clean, it could be time to replace it 

2. Dirt in the spark plug

The surprising thing about dirt is that the pesky particles of dirt can gather up at any place. Dirt doesn’t just accumulate in air filters, but it can also accumulate in the spark arrestors. Spark plugs can get dirty as well.

The excess carbon on spark plugs will indicate that there is an excess thickness in the oil mixture. If the oil is too thick, excess carbon will accumulate on the spark plugs and arrestors. As a result, they will become dirt and in turn, the chainsaw will die under load. Further, when the spark plugs and arrestors get dirty, they can also contribute to overheating of the chainsaw.

Solution

  • First, you should remove the spark arrestors from the mufflers of the chainsaw (normally, spark arrestors will be placed behind the mufflers)
  • Once you have done that, clean it using a wire brush 
  • As plugs are delicate in nature, you should be careful about choosing the appropriate one as there are different brands of wire brush available in the market
  • To clean the spark plug, you’ll need to get a proper batch of mixed oil
  • This will do the trick since oil doesn’t have much thickness 
Chainsaw Bogging Down: The Solution That Always Works.

3. Carburetor

The carburetor alone could be the cause and solution to your chainsaw bogging down. It will be responsible for mixing fuel and supplying the fuel to the engine. It is also the orientation that keeps it working properly and smoothly on little or full throttle. There are numerous carburetor-related problems like carburetor clogs, excessive smoke release, imbalance in the fuel mixture, misalignment of screws, and more.

Solution

  • Dealing with the carburetor will require strict guidelines to be followed.
  • You need to pull the starting cord for checking resistance. This will help it identify compression. In case there isn’t any, you should take off the cover and locate the carburetor. 
  • You can work on it using a carburetor adjustment tool. Adjusting the H screw helps in achieving optimal performance.
  • Tuning will regulate the flow of fuel, although it could be the last resort. For this, you need to seek professional help.
  • A clean, fixed carburetor will be key to achieving full-throttle performance. For this, you will need a carburetor cleaner.
  • Fill up the tank with the appropriate gas-to-oil ratio.

4. Spark arrestor

You simply cannot hide from dirt. Even with the tiniest passage, it could make its way toward anything, including the spark arrestor. A thick fuel mixture could result in excessive carbon around the spark plug, which could kill the chainsaw. A dirty arrestor, on the other hand, could be the cause of overheating that you experience in a bog down.

Solution

  • Spark arrestor is generally placed behind the muffler, so locating it wouldn’t be that hard.
  • Take them out and clean them with a delicate brush.
  • You can also use a plug spray-on for cleaning the thick carbon.

5. Alignment of high-speed screw

Misaligned screws could cause bogging down, lower performance efficiency, and smoking in the chainsaw. Locate the screws on the carburetor and then check if all of them are properly aligned.

Solution

  • Take a screwdriver and align them
  • Ensure that they are closed at a distance such that neither of them is touching the engine and aren’t too far from it.
  • This speed will be perfect and there wouldn’t be any unusual sound when the screws are aligned properly.
  • You can use a chainsaw RPM reader for making sure 

6. Fuel ratio

The motor of your chainsaw is essentially a combustion system that depends on an adequate ratio of air, gas, and oil. An imbalance will be one of the major reasons for bogging down.

Bog down is usually experienced at full throttle. This issue can be easily resolved with the help of the user manual that you received with your chainsaw. It has the exact ratio requirement of oil and gas for your specific model. If you have lost it, most chainsaws will follow the following gas-to-oil ratio –

  • 30:1
  • 40:1
  • 50:1

Solution

These days, most chainsaws make use of a 50:1 ratio, but some of them also use a 40:1 or 30:1 ratio. The latter is recommended for older models. If you have filled it wrong, you should drain it and then replace it with the correct mix.

How to Maintain the Chainsaw and Prevent Any Bogging

Often, when a chainsaw has bogging issues, it is due to poor maintenance of the machine. Taking care of your chainsaw before and after use and inspecting different components for wear and tear throughout the season will help you identify any potential problems. Identifying the problems beforehand will help you prevent them before they become serious enough to cause any permanent damage to the engine or cause it to stall completely.

Here are a few ways you can keep the chainsaw properly maintained to prevent issues with bogging –

1. Clean the chainsaw

One of the biggest issues with chainsaws that can damage their engine will be the build-up of sawdust and other debris during the process of running during the cut. Cleaning the chainsaw thoroughly before and after use will help prevent the build-up that leads to clogged air filters and carburetors.

2. Use new or stabilized gas

As a general rule of thumb, you should not be using gas that has been stored in the chainsaw’s gas tank for over 30 days, unless you have added a fuel stabilizer. Stabilizers are designed for helping keep fuel stable and fresh for months.

resting chainsaw and log

3. Lubricate the chain

Lack of lubrication could cause the chainsaw to work harder than it has to due to the added friction and heat. This will, in turn, result in bogging. If left unchecked, overheating related to friction could stall the chainsaw or damage it. Keeping the chainsaw lubricated with bar oil will ensure that it cuts clean without stalling or overheating.

4. Sharpen the blades

Running a dull chainsaw could be the quickest way to wear out the motor. Further, it could result in undue wear and tear to the rest of the chainsaw too. Chainsaw blades could be sharpened with a metal file at home, or you could take the chainsaw to a small engine repair shop to get it sharpened.

Keeping up with the chainsaw maintenance each time you are using it can increase the lifespan of your machine significantly. Since chainsaws are not exactly cheap, it will be worth it to take the time to keep the engine cared for during and in between uses.

FAQs

Why do Husqvarna chainsaws bog down at full throttle?

A Husqvarna chainsaw could bog down because of a spark arrester or a clogged air filter. Clogging will slow down the engine from in-taking fuel and air, which can result in a bog down at full throttle.

Why do Stihl chainsaws bog down when cutting?

The reason this could be happening is that you are using the chainsaw at an altitude, or the carburetor adjustment could have slipped and is in need of fixing. Bogging down could occur in the case of a dirty air filter, carburetor, or spark arrestor.

You can easily troubleshoot the Stihl chainsaw by adjusting the carburetor screws, cleaning the filters and muffler, and giving it a fresh fuel change.

Why do Echo chainsaws bog down when cutting?

The primary reason why your Echo chainsaw could be bogging down is due to a dirty spark arrestor. This should be the first thing that you check and clean. After that, you need to check the air filter and carburetor for any dirt or debris.

What causes the chainsaw to bog down when accelerating?

Dirty filters are the primary problem here. After checking and cleaning the filters, you should see if the carburetor orientation is proper.


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Mike
Hi, I'm Mike - but my friends call me Backyard Mike. I'm the founder of this website, and I'm addicted to outdoor power tools. I love to work with wood and share my knowledge here on this website with you. You can find more about me here.