Preparing Your Stihl Chainsaw for Starting
Getting your Stihl chainsaw ready to run involves more than just pulling the starter cord. A few preparatory steps are vital for both safety and ensuring the engine fires up correctly. These actions minimise wear, prevent potential hazards, and make the cranking process smoother.
Before you even think about pulling the cord, ensure the chainsaw is on a stable, flat surface. It should be clear of any flammable materials. Check that the chain brake is engaged; this is a critical safety feature that prevents the chain from moving unexpectedly when the engine starts. Always wear appropriate personal protective equipment, including safety glasses, gloves, and hearing protection. A properly maintained saw is also easier to start, so briefly inspect the chain for tension and the air filter for cleanliness.
Essential Pre-Start Checks
- Safety First: Ensure the chain brake is engaged and wear all recommended safety gear.
- Stable Surface: Place the chainsaw on level ground, away from debris.
- Fuel Check: Verify the fuel tank has the correct Stihl two-stroke fuel mix.
- Air Filter: Make sure the air filter is clean; a clogged filter hinders starting.
- Spark Plug Cap: Confirm the spark plug cap is securely attached.
These checks form the foundation for a successful start. Neglecting them can lead to difficulty in starting or, more importantly, unsafe operating conditions.
Secure the Handle: Before pulling the starter cord, firmly grip the front handle with your non-dominant hand to keep the saw stable and prevent it from moving.
Understanding these preliminary actions is key. They not only prepare the machine but also prepare you for the task, ensuring a controlled and effective start to your work.
The Correct Procedure for Cranking a Stihl Chainsaw
Starting a Stihl chainsaw typically involves a specific sequence, especially for models without an automatic decompression valve. The aim is to prime the engine and set it up for ignition. Different Stihl models might have slight variations, but the core principles remain consistent. For many, the process begins with setting the choke.
Choke and Primer Bulb Operation
When the engine is cold, you'll often need to set the choke to enrich the fuel-air mixture. Locate the choke lever (usually near the air filter) and move it to the 'choke' or 'cold start' position. If your Stihl chainsaw has a primer bulb, press it several times (usually 3-5) until you see fuel moving within the bulb. This action draws fuel into the carburettor, making it easier for the engine to start.
Engaging the Throttle Lock
Next, engage the throttle lock. This is often a small lever or button near the throttle trigger that, when engaged, holds the throttle partially open. This is crucial for starting; it prevents the engine from flooding and helps it run once it fires. On many Stihl models, you'll press the throttle trigger, then engage the throttle lock. Consult your specific model's manual if unsure.
Pulling the Starter Cord
Now, with the saw stable and the front handle secured, grasp the starter cord handle firmly. Pull the cord out steadily until you feel resistance, then give it a sharp, brisk pull. You should hear the engine attempt to fire or 'cough'. This is the signal that the fuel mixture is correct.
Transitioning to Running
Once the engine coughs, immediately disengage the throttle lock and move the choke lever back to the 'run' or 'warm' position. Pull the starter cord again. The engine should now start and run. Allow it to run for a short period, perhaps 10-20 seconds, to warm up before applying full throttle.
The transition from a cold start cough to a running engine is critical; acting promptly to adjust the choke and disengage the throttle lock prevents the engine from stalling or becoming oversaturated with fuel.
If the engine doesn't start after the first few pulls with the choke on, you may need to repeat the sequence. However, be cautious not to over-pull, as this can flood the engine.
Troubleshooting Common Starting Issues
Even with the correct procedure, Stihl chainsaws can sometimes be stubborn to start. Most issues stem from simple, fixable problems rather than serious faults. Understanding these common pitfalls can save you considerable frustration and downtime.
When the Engine Won't Fire (No Cough)
If you pull the cord and hear nothing, or only hear the cord pull without any engine noise, the problem likely lies with fuel delivery or ignition. Check that the spark plug cap is firmly attached. Ensure you have the correct fuel mix in the tank and that the primer bulb is working. A blocked fuel filter or a dirty air filter can also prevent fuel from reaching the carburettor. If these are all in order, the spark plug itself might be fouled or faulty, or there could be an issue with the ignition system.
When the Engine Fires but Stalls
If the engine starts, coughs, or runs briefly and then dies, it usually indicates that the fuel-air mixture is too rich or the throttle lock wasn't disengaged correctly. Make sure you've moved the choke to the 'run' position after the initial cough. If the engine still stalls, try starting it again without using the choke (if the engine is warm) or with fewer primer bulb presses. A partially open throttle lock can also cause stalling; ensure it's fully disengaged.
Flooded Engine Symptoms
An engine can become flooded if too much fuel enters the combustion chamber, often from excessive pulling with the choke engaged. Symptoms include a strong smell of petrol, the engine feeling 'waterlogged', or not firing at all. To clear a flooded engine, set the choke to the 'run' position, disengage the throttle lock, and pull the starter cord several times. This helps to clear excess fuel. You might also remove the spark plug, pull the cord a few times to clear the cylinder, then reattach the spark plug and try starting again.
Consult Your Manual: Always refer to your specific Stihl chainsaw model's operating manual. It provides detailed troubleshooting steps tailored to your saw's features, which can be invaluable when facing starting difficulties.
Addressing these common starting challenges systematically will help you get your Stihl chainsaw operational quickly and safely. Regular maintenance, such as keeping the air filter clean and using fresh fuel, is the best defence against these issues.
Alternatives and Maintenance for Reliable Starting
While the core procedure for cranking a Stihl chainsaw is consistent, considering alternatives in maintenance and usage can significantly improve reliability. Focusing on the saw's condition ensures that when you need to start it, it's ready to go without fuss.
Fuel and Oil Mix Importance
The correct fuel-to-oil ratio is paramount for two-stroke engines like those in Stihl chainsaws. Using the wrong mix or old fuel can lead to poor performance, difficult starting, and engine damage. Always use a high-quality two-stroke oil specifically designed for air-cooled engines and adhere strictly to Stihl's recommended mix ratio (often 50:1 with premium fuel). Fresh fuel is also vital; fuel left standing for extended periods can degrade and cause starting problems.
Spark Plug Maintenance
The spark plug is a small but critical component for ignition. It should be checked periodically and replaced as recommended by Stihl. A fouled, worn, or incorrectly gapped spark plug will make starting difficult or impossible. When checking, look for signs of wear, carbon build-up, or damage. Ensure the gap is set correctly according to your chainsaw model's specifications, typically found in the user manual.
Air Filter and Carburettor Care
A clean air filter is essential for proper engine combustion. If it's blocked with sawdust or debris, the engine will struggle to get enough air, leading to poor running and starting issues. Regularly clean or replace the air filter according to your usage. While more advanced, a properly functioning carburettor is also key. If starting issues persist despite other checks, the carburettor may need adjustment or cleaning by a qualified technician. For users who also handle hedge trimming, the principle of keeping air filters clean applies equally to ensuring their hedge trimmer operates efficiently.
The right maintenance ensures the engine receives the correct fuel-air mixture for ignition.
Consider Engine Decompression
Some newer or professional Stihl chainsaw models feature an automatic decompression valve. This system vents a small amount of cylinder pressure when you pull the starter cord, reducing the resistance and making it significantly easier to crank the engine. If your model doesn't have this feature, the physical effort required to pull the cord can be substantial, especially for less powerful users. While not an 'alternative' starting method, understanding if your saw has this feature explains why some models are easier to start than others.
By focusing on these maintenance aspects, you are effectively optimising the conditions for your Stihl chainsaw to start correctly every time, reducing the need for repeated or forceful cranking.