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In a perfect world, starting a Stihl chainsaw shouldn't be an issue.
After all, Stihl is one of the best chainsaw manufactures in the world.
However, what happens when you try to start your brand new saw, or maybe your chainsaw has been sitting for a few months and now it simply doesn't want to run?
Cranking a chainsaw that refuses to start is perhaps one of the most annoying experiences a person can endure.
What is the problem?
Is it a spark-related issue?
Is it a gas-related issue?
The list can seem endless - and yet the wood pile remains uncut as you try to figure out why.
In this post, we’ll give you some more information on why your Stihl chainsaw won’t start - and what you can do to fix it.
If you are a first-time user of a Stihl chainsaw, it is always recommended that you look at the manual first before starting the saw for the first time.
Read it carefully for proper starting techniques and maintenance of the saw - and take a close look at the safety instructions to prevent injury.
Check the fuel in the saw before starting.
If needed, fill both fuel and oil reservoirs and retighten caps.
Next, the chain brake should be activated to prevent the chain from turning while starting.
Remove the bar cover if the saw is equipped with one.
Press the decompression valve, if your particular Stihl is equipped with this feature.
This will reduce compression, making the saw much easier to crank over, especially in cold weather.
If your saw has a primer valve or bulb, press this several times.
This will circulate fuel to the carburetor.
This valve or bulb is located on the side of the saw near the top handle.
Moving forward, find the master control switch located on the rear of the powerhead on the left side of the chainsaw.
Set the master control to the cold start setting, which is always the setting farthest down.
You will have to press and hold the throttle lockout mechanism, which is located on the top side of the rear handle directly above the trigger.
Now you are ready to start the saw.
Put the saw firmly on the ground being certain the bar tip can not come into contact with the ground.
Always check to be sure no one is near you when starting your saw.
With the saw on the ground, put your right foot into the rear handle as far as possible and firmly grasp the top handle with your left hand.
Keep your left arm as straight as possible, locking your elbow for safety.
Grasp the starter cord handle and firmly pull the cord.
Continue to pull until the chainsaw fires.
Once the saw fires, it will immediately quit.
Move the master control up one setting to the half throttle or warm setting and continue to crank.
Once the saw starts and is running, move master control up one notch to the idle setting.
Now that your saw is running, stand up with the saw, release the chain brake and you are ready to cut.
Again, for safety, always observe your surroundings for other people and obstructions.
If you're starting a Stihl chainsaw that has been sitting for any length of time, especially over the winter, it would be best to first drain the gas.
With the gas cover still off, let it stand for 30 minutes to let excess gas evaporate.
Next, remove the spark plug, dry it off and crank the engine with the plug still removed to dry the cylinder.
Refuel the saw and refit the spark plug, and the saw should be ready to start.
The procedure for a cold start has been shown above in this post, but to quickly review, move the master control to full choke position all the way down.
If equipped with a primer valve or bulb, depress several times to circulate the fuel.
Be sure to depress the decompression valve if your Stihl is equipped with one.
This is extremely important in cold weather, as this greatly reduces compression allowing easier cranking.
With the saw on the ground, and the chain brake engaged, crank the engine until it fires.
Once it fires, move the master switch up one notch to the half-choke position and pull over again.
You may have to crank it three or four more times.
Once the saw starts and runs, simply hit the throttle just a bit to put the saw master switch into run position.
At this point you are ready to go.
Safety should always be first and foremost when starting any power tool, especially a chainsaw.
Reviewing the safety features aforementioned in this post, remember to always have the Stihl on the ground with the right foot through the rear handle and the left hand on the top handle.
Be certain the chain brake has been engaged.
Take the time to be sure all other people and obstructions are clear as you stand with your now running chainsaw.
Here are some of the most common reasons why your Stihl chainsaw might not start.
Clogged Carburetor or Plugged Fuel Lines
Let's begin with a clogged carburetor.
All too often, the gasoline we have today, if left sitting for too long in your saw, will begin to gel up.
Ethanol added to the gas is the main culprit in this issue.
This sticky gel will always find its way into the carburetor and the gas lines, plugging them up and depriving the saw of fuel.
To correct this issue, start by inspecting the gas filter in the fuel tank.
Over time. they can become clogged with debris that can enter the tank while fueling.
Proper maintenance should include periodic replacement of this filter.
Another common issue is plugged fuel lines.
Inspect the lines for visible tears or clogs.
Replace the lines if needed.
Should you determine that the carburetor is definitely clogged on your saw, you may be able to clear it by removing all the old gas from the tank.
Once clean, dump the recommended amount of either SeaFoam or Sta-Bil into the tank and start the saw.
Let it idle for several minutes to let the product work its way into the carburetor.
If the chainsaw still won’t start, you may need to replace the carburetor.
For some saw owners, it may be best to take them to a repair shop.
Replacing a carburetor is relatively easy, but adjusting the carburetor, once installed, may be a bit more challenging.
If you’ve determined that the carburetor and fuel lines are fine, the next thing to check is the ignition.
Ignition problems could be preventing your saw from starting properly.
Check the wiring connections and look for broken wires.
The problem could also be a faulty ignition module or oxidized spark plugs.
Checking for spark should be the first on the list for ignition problems.
Remove the saw cover so that you may access the spark plug.
Remove the plug and reinstall it back into the plug wire.
Let the spark plug rest against the top of the engine so it's grounded to a piece of metal.
Be careful not to touch the plug while cranking the saw, as a properly firing plug will give you a shock.
Replace the spark plug if you are unable to see a spark.
Faulty ignition coils will prevent your Stihl from starting properly as well.
A bad coil will not produce the voltage needed by the spark plug to start.
Check with an ohmmeter to look for a break in continuity.
If a break is detected, the ignition coil will have to be replaced.
Plugged Air Filter
Check the air filter on your saw.
If not properly maintained, the air filter will eventually become plugged to the point where the carburetor will not get enough air to function properly.
Stihl air filters can be simply taken off and tapped against a hard surface, a process that will allow any built-up debris to fall out.
Do not brush a fleece air filter, as this will lodge debris back into the filter.
Should a filter be extremely dirty, it can be washed in a mild dish detergent and then run water through it to rinse it out.
Keep running water through until it becomes clear, ensuring that the filter is clean.
Regular replacement of air filters is highly recommended, especially for more frequent users.
Remember, the proper amount of air is essential for the chainsaw to start and run properly.
Starting a Stihl chainsaw does not have to be a daunting task.
Hopefully, this post has given you some insight into getting your Stihl chainsaw up and running - even if you have issues on the first or second try.
Many mechanical and maintenance issues can be addressed with just a small bit of guidance, such as this post.
If you’re still having trouble, you can always check with your local Stihl dealer or repair shop who can service any additional issues you may encounter.