How To Adjust A Poulan Chainsaw Carburetor Properly?

If your Poulan chainsaw starts to act up, the first thing you have to do is to check the carburetor. 

The carburetor regulates the fuel and air mixture ratio in the engine. So if it works incorrectly, your chainsaw will run poorly as well. 

Luckily, adjusting is not that tough if you know how to adjust a Poulan chainsaw carburetor properly. It will not take more than a few minutes.

Start by understanding the mechanism of the carburetor. Then start adjusting different parts of the carburetor including idle speed, high and low-speed adjustment, and fuel ratio. Do not forget to maintain safety since you are dealing with a risky machine.

How to adjust a Poulan chainsaw carburetor

How To Adjust A Poulan Chainsaw Carburetor

Here you will know a detailed overview of adjusting a Poulan chainsaw carburetor.

Poulan chainsaw carburetor adjustment tool

  • Spline screw
  • Spline dent tool
  • Cleaning brush
  • Dry cloth

Step 1: Understanding the chainsaw carburetor and its setting

The chainsaw carburetor works on the performance of its carb. If your engine is idling, even then it has to work. It also has to work when you are trying to start the engine cold and the engine is wide open. 

The ideal carburetor settings for the Poulan chainsaw are pretty straightforward. All you need is a tachometer. At idle conditions, the adjustment should generate around 2800 – 3400 RPMs. In the case of full-throttle, it should be around 12,000-12,500 RPMs. 

Step 2. Closing the low and high-speed jets 

  • Determine the low-speed jet (marked L on carburetor) and high-speed jet (marked H on carburetor) at first. 
  • Apply the special adjustment tool so that you can set both jets all the way closed. 
  • To do this efficiently, turn both jets clockwise until they stop.

Step 3. Turning the jets

  • Turn both the low-speed jet and high-speed jet closed using the special adjustment tool.
  • Raise the turns slowly and it’s recommended to stop reaching at 1.5 turns

Step 4. Low-speed jet adjustment

  • Now, adjust the low-speed jet (marked L on carburetor) to the desired point.
  • If you can’t determine the exact point, use the point where the chain stops turning. 
  • When the chain stops, notice if the throttle is still responsive. Otherwise, the adjustment isn’t accurate. 

Step 5. Adjusting the high-speed jet 

  • Similarly, adjust the high-speed jet (marked H on carburetor) to the desired point.
  • If you face trouble in determining that point, notice where the engine archives maximum allowed RPMs. 
  • If you intentionally cross the RPM level, the chainsaw speed will be wasted sooner or later. 

Step 6. Adjusting the idle screw (Optional)

  • If you set the idle adjustment too high, the chain will keep moving.  
  • If you set the idle adjustment too low, the chainsaw will stop by itself slowly.

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How do you adjust the fuel and air mixture on a Poulan Pro chainsaw?

A lot of people asked on the internet- how to adjust the carburetor on a Poulan pro 42cc chainsaw? This part discusses a detailed adjusting process of the fuel and air mixture on a Poulan pro chainsaw. 

Start cleaning 

  • Take out the filter from your Poulan chainsaw. 
  • Then, clean its dirty filter by following proper regulations

Knowing about the correct fuel ratio

  • The ideal fuel/oil ratio is 40:1, or 3.2 ounces of oil per gallon of gasoline
  • If the Poulan chainsaw engine runs sluggish, changing the amount of fuel is mandatory.  
  • Turn the adjustment screws on the side of the carburetor to do this easily

Finishing the adjustment

  • To replace the filter, start your Poulan chainsaw in a regular manner.
  • Now, turn the “T” screw counterclockwise to increase the fuel mixture as well as the idle speed.
  • If you turn the screw counterclockwise, it’ll decrease both the fuel mixture and idle speed.

Congratulations! You’ve achieved the proper fuel mixture. It happens when you can successfully idle down the engine, but the chain doesn’t spin.

How do you adjust the idle speed on a chainsaw?

How To Adjust A Poulan Chainsaw Carburetor

Idle speed adjustment has two segments: one screw and three-screw idle speed adjustment. Here are the easy steps to understand both adjustments.  

One-screw idle adjustment

  • The first responsibility is to fire up your chainsaw and get a flat-head screwdriver ready
  • Now, turn the screw clockwise or counterclockwise at this step
  • Next, observe the engine’s behavior changes both while you’re throttling it and idling
  • If the chainsaw won’t stop spinning when idling, it’s necessary to back it down. 
  • If the chainsaw is accelerating slowly, it’s suffering from an insufficient fuel issue
  • Note down the time when the screw is running lean or rich. 
  • The perfect one-screw idle adjustment can be found between the lean or rich points. 

Three-screw idle adjustment

  • To execute this step, you need to find the “LA” screw. 
  • Start the adjustment by adjusting the LA screw
  • For low-speed adjustment, turn the “L” screw accordingly.
  • The “H” screw is for high-speed adjustment. Follow the same manner of the low-speed adjustment for this operation

An additional tip: it’s recommended not to adjust the screw more than ¼ turn either way.

  • Now, follow the single-screw adjusting process to complete this step. Find the lean and rich points and stop at the medium point between them.

How to ensure proper high and low-speed adjustment

How To Adjust A Poulan Chainsaw Carburetor

How to ensure proper high and low-speed adjustment

The high and low-speed adjustment is all about controlling the engine speed. Let’s have more detailed information about this adjustment process. 

Understanding “H” and “L”

Before starting, you need to understand what is meant by “H” and “L” on the chainsaw. The label of adjustment screws is marked with these two letters. The “H” mark on a chainsaw indicates its high-speed adjustment and the “L” mark talks about the low-speed adjustment. 

Adjusting the speed

  • First, locate the idle speed screw 
  • Next, start the chainsaw in a regular manner
  • Now, insert a flat-head screwdriver into the idle speed screw
  • Turn the instrument clockwise so that the engine speed increases
  • Keep turning the screw counterclockwise until the engine stops
  • After a while, the desired speed adjustment will be fixed 

What about adjusting the screws?

Almost every chainsaw comes with three adjustment screws. They’re throttle stop screws, low-speed fuel adjustment screws, and high-speed fuel adjustment screws. Let’s get a quick overview of them. 

Throttle stop screws

  • Your first task is to find the throttle stop screws from above the primer valve
  • For additional information, these are widely known as the “idle speed” screws that control the throttle valve.
  • When you enable the low adjustment by releasing the throttle trigger, the engine will die. 
  • If you perform the opposite action, the centrifugal clutch will engage and the chain will run. 

Low-speed jet screws

  • These jet screws control the proportion of fuel in the combustible air/fuel mixture at idle speed
  • The too-rich adjustment will cause the engine to load up and die at idle speed.
  • If the adjustment is extremely lean, the engine will die too. 

High-speed jet screws

  • These jet screws control the proportion of fuel in the combustible air/fuel mixture at cutting speed
  • If the adjustment is too rich, the desired RPM level can’t be achieved. As a result, the maximum power can’t be generated. 
  • Too lean adjustment can lead the chainsaw to bear failure and cylinder seizure
  • For user convenience, the high-speed jet screws are alternated with the “fixed jets” in a few models. The adjustment procedure isn’t different for them. 

Safety measurement

A chainsaw is a dangerous instrument that can even cause deadly injuries. By following some safety precautions, you can easily avoid the risks. 

  • Place your Poulan chainsaw on a flat surface before starting any operation. 
  • Wear protective equipment like goggles, hand gloves, helmets, and others. 
  • Ensure that the connection is secured and the tool won’t run accidentally.
  • Always keep your eyes on the sharp edges so that they can damage your skin entirely.

Time to wrap up

Adjusting the Poulan chainsaw carburetor brings the highest perfection to your desired operation. Before understanding how to adjust a Poulan chainsaw carburetor, you should know about the carburetor precisely.

Also, it’s important to understand the speed adjustments for the best output. Another important part is maintaining the correct fuel ratio. Even if the idle, high and low-speed adjustment is okay, the chainsaw won’t work for an inappropriate fuel mixture.

There are three types of screws that control most of the activities of your Poulan chainsaw. Unless you understand their working procedure, you can barely adjust the chainsaw. The last message is- don’t forget to equip yourself with the necessary safety while dealing with a chainsaw.

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Johnathan Brewer

Hello, I’m Johnathan Brewer, a professional woodworker and power tools salesperson. I’ve worked with top interior designers and architects of the city. With an experience of 11 years in this field, I can suggest the best tips for bigger DIYers. I help my friends and neighbors with their tools. I specialize in restoring, repairing, designing, and decorating. There are even some great woodworking tactics that I’d love to share with you. With that information and suggestions, you can do really good professional work in a very short time.

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