Echo SRM225 Only Runs On Choke [Solved]

Hey there! Some links on this page are affiliate links which means that, if you choose to make a purchase, I may earn a small commission at no extra cost to you. I greatly appreciate your support!

Many people face the issue of their Echo string trimmer only running when the choke is on.

If you’re experiencing this problem, this repair guide lists some common issues and their solutions to help you fix your Echo string trimmer. By following these steps, you can ensure that your trimmer runs smoothly even when the choke is off.

So, without further ado, let’s get started…

The Echo SRM 225 is a popular string trimmer known for its robust start technology, making it easy to start with minimal effort. However, over time and due to improper maintenance, internal parts may develop problems.

While some issues can be resolved easily on your own, more significant problems may require the assistance of an expert.

Reasons for Echo SRM225 Only Running When the Choke Is On

There can be several reasons why the Echo SRM 225 does not run when the choke is off.

First, let’s understand…

How does the Echo SRM225 Choke Work?

The choke in an Echo SRM225 serves as a plate within the carburetor that blends air and fuel, delivering this mixture to the carburetor. Once ignited, this fuel-air mixture combusts inside the engine, generating significant energy. Equipped with an on/off button, the choke is typically set to the ‘on’ position by default. This restricts the entry of air into the carburetor, creating a vacuum within the chamber.

The choke is particularly useful for starting a cold engine. During cold starts, the engine necessitates a higher fuel supply to facilitate warming up. By limiting the entry of air into the chamber, the choke assists in this process.

A temperature-sensing spring is responsible for monitoring the internal temperature. When necessary, it closes the choke plate to regulate the amount of air inside the engine, maintaining its temperature effectively.

What Happened When the Echo SRM225 Runs with the Choke On?

If your Echo string trimmer only runs when the choke is on, it indicates that the engine is not receiving a sufficient supply of the fuel and air mixture.

Echo SRM225

Disadvantages of Running the Echo SRM225 With the Choke On

  • Increased Fuel Consumption: Running the trimmer with the choke on can lead to higher fuel consumption, as the engine is receiving an overly rich fuel mixture.
  • Reduced Engine Performance: The engine may experience a decrease in performance when running with the choke on, as it is not receiving the optimal air-to-fuel ratio for efficient combustion.
  • Potential Engine Damage: Prolonged operation with the choke on can potentially damage the engine due to the rich fuel mixture, leading to issues such as fouled spark plugs or carbon buildup in the combustion chamber.

Also Read: Weed Eater Stalls When Given Throttle [Solved]

5 Easy Solutions of Echo SRM225 Running Only When The Choke is On

1. Check The Choke Plate

When the engine is cold, its choke plate is normally on. Remove the cap, and here you will find an air filter; after removing this, you will see two screws. Remove them using a 27I screwdriver.

Now remove the plastic seal with your hand. In most cases, when you use the Echo string trimmer for a long time, its choke plate creates problems. Simply replace it with a new one.

2. Change The Fuel Line And Fuel Filter

Fuel flows through the fuel line that is connected to the carburetor. It manages the quantity of fuel that the engine should receive. Sometimes it needs replacement because, in most cases, when the engine doesn’t receive enough fuel supply, the problem arises.

With time, the fuel filter gets clogged. You will find the fuel filter in the small fuel tank. Just open its cap and remove it with your hand, then replace it with a new one.

Your problem of Echo SRM 225 running only when the choke is on can be solved if the fuel filter becomes useless.

3. Clean The Air Filter

Sometimes the air filter gets clogged from dust and debris, and this may be one reason for your problem. Check it by opening the cap and simply removing the air filter with your hand.

To clean the air filter, simply blow air with pressure on it, and all the dust particles will get cleaned. Now assemble it and check if your problem is solved or not.

4. Check The Carburetor

Due to dust and debris, the carburetor needs to be cleaned well. For this, you have to remove the carburetor from the trimmer. Check all the seals and ensure that the carburetor is in good condition. If it is damaged, replace it with a new one.

Tools required to remove the carburetor from the Echo SRM225 trimmer

The maintenance kit comes with all the tools:

  1. Spark plug
  2. Carburetor
  3. 2 mounting gasket
  4. 2 Primer bulb
  5. Air filter
  6. Fuel filter
  7. 3 fuel lines
  8. Grommet
  9. Vent

First, you need to remove the air filter cover, and it is very easy to remove it. After that, there are two screws that can be removed using any T25-compatible screwdriver.

After removing the plastic case, you will see that the whole carburetor assembly comes out. Now, to remove the carburetor, simply remove its throttle cable using a wrench tool (maybe 10mm).

Now remove all outlet connectors using your hand. Now you have successfully removed the old carburetor from the machine. Look at the gasket and remove it gently using your finger and peel it off.

Now replace the old gasket with the new one. It may not look like the original one, but it works. Now take the new carburetor and assemble the whole unit as you removed the old assembly.

You may find it difficult to attach the throttle cable. I’ll give you the simplest way to do so.

Check a little hole at the end of the moving screw. Now align the screw gap with the hole and place the throttle cable inside it and move it toward the bulb and tighten its screw with the wrench, and that’s it.

5. Seek Expert Help

If all the above-listed methods do not work, it means there is some kind of serious problem that requires the help of an expert. Maybe the problem is inside the engine assembly (piston, etc.). If your Echo SRM225 trimmer is old, then such repairs might cost you much more, and it would be better to buy a new grass trimmer for your lawn.


I hope this article helps you to fix the issue with your Echo SRM225. I have tried to provide some genuine solutions that actually work. If your Echo string trimmer still won’t start without choking, then seek the help of an expert or consider purchasing a new one.

Helpful Links:

Echo SRM225 technical document

About The Author


Adam is here, I'm an Editor and writer on guidingpapa. I love to share home improvement tips and new ideas in this blog. I have been doing this from couple of years and I'm very passionate about it.

Leave a Comment