The choke lever plays an essential role in chainsaw operations because it adjusts the fuel-to-air ratio to make it easier to start the chainsaw from cold. However, it’ll be impossible to start your chainsaw if it malfunctions.
Three common Stihl chainsaw choke lever problems are the lever being stuck in one position or a lever that doesn’t generate power. Another cause could be a new chain that’s jamming the choke lever. Fixes include replacing the choke lever, adjusting the chain length, and fixing the throttle cable.
In the rest of the article, I’ll explain these choke lever problems in-depth and discuss some helpful solutions. Let’s get started!
1. The Choke Lever Is Stuck In One Position
A properly-functioning chainsaw choke lever should easily move between the closed and open positions to facilitate cold and warm starts.
When the chainsaw is stuck in the closed choke position, it restricts airflow and increases the fuel level in the cylinder. This can cause the chainsaw to work inefficiently (source).
Too much fuel also carries operational risks for the carburetor and cylinder.
When your Stihl chainsaw only allows you to set it to the closed choke position, there is a problem with the plastic part on the master control lever operating the choke mechanism (source). This likely means that the plastic pawl is broken; you can check this by removing the cover.
Another common issue with Stihl chainsaws is when the choke lever cannot hold its position. This forces the user to hold it in the correct place on the master control lever when starting the chainsaw.
You might need to keep holding it down while running the chainsaw, which is inconvenient and unsafe because your saw could cut out at any point.
The main reason a choke lever cannot hold its position is a worn-out or damaged choke operation mechanism. The mechanism is made of plastic and can become damaged and brittle over time.
How to Fix
Unfortunately, if the pawl is broken, you won’t be able to fix the problem yourself, and you will need to send the chainsaw to a technician for repair.
If the pawl is jammed, you can try releasing it so that it switches between the open and closed position again.
The best solution for a worn-out or broken choke lever is to replace it. You can take it to a power tool technician or replace the part yourself if you feel comfortable doing so.
If you are replacing the part yourself, consult your chainsaw’s user manual for the model number, and order a Stihl-approved replacement online.
I recommend the Switch Shaft/Choke Lever Rod (link to Amazon). This replacement product is made from high-quality material, and you can use it for various Stihl chainsaw models, including:
- MS250
- MS230
- MS210
- MS025
- MS023
- MS021
Once you have the new part, follow these steps to replace the faulty chainsaw choke lever:
- Unscrew and remove your chainsaw’s top cover and the air filter underneath.
- Locate the choke lever, unscrew it from its position, and set it aside. If you’re struggling to find it, it is the plastic lever near the carburetor link.
- Fix the new choke lever in position and screw it in.
- Replace the air filter and chainsaw cover.
2. A New Chain Is Jamming the Choke Lever
A chainsaw chain requires regular replacement, and some people even change their chains as regularly as every two days.
If you don’t replace the chain properly or use one that is the incorrect size, it can cause problems with the choke lever (source). As a result, the choke lever could become stuck in one position.
An incorrect chainsaw chain size disorients the clutches, which jams several other components, including the master control lever.
When the lever jams at the open position, cold starting your Stihl chainsaw is a problem.
How to Fix
Chain length is an easy problem to solve, and you can follow the below steps to remedy the problem:
- Find the recommended chain length from your user manual and reduce or increase the chain length accordingly.
- Once your chainsaw has the correct size chain length, it should start operating normally, and your choke lever should easily move to the cold start position.
3. The Choke Doesn’t Generate Any Power
A choke not generating power is a common problem with Stihl chainsaws as they age. When this happens, you will find that when the choke level moves to the on position, it doesn’t generate any power.
A properly functioning choke on a Stihl chainsaw generates power by closing airflow and allowing the engine to run rich for an easy start.
When the choke doesn’t generate any power, the throttle cable and the throttle level have no connection. The disconnection occurs after continuous jostling of the lever during normal operation. Fortunately, this is a problem you can easily fix with the right tools.
How to Fix
This problem involves taking your carburetor apart to access the throttle cable attachment point. You can do this by following these steps:
- Remove your chainsaw’s air filter cover, and disconnect the spark plug for safety.
- Use a socket wrench to tighten all four bolts attaching your carburetor housing to the block.
- Lift the carburetor block and disconnect any connecting wires and hoses. Be sure to disconnect the fuel line from the main tank.
- You will now have easy access to your carburetor. Fix the throttle cable on the level and reassemble your Stihl chainsaw.
- Be careful to return every hose or wire to its original right connection.
Final Thoughts
The choke function on Stihl chainsaws is controlled by the master control lever, which can malfunction and cause problems with warm and cold starting. These faults in choke operations can cause cutting delays, leading to frustration. The plastic choke operating mechanism on the master control lever is the leading cause of these faults.
Replacement is the best option when the lever starts jamming or failing to hold to position, and repairs might require technical assistance and only be a temporary fix. I recommend reading the user manual to prevent damage to your chainsaw or bodily harm after replacement.
