Many owners of gas-powered tools are faced with a situation where, after winter downtime or a long break, the saw refuses to start. This often causes panic, especially among beginners who do not yet know the specifics of two-stroke internal combustion engines. Correct launch algorithm Stihl depends on many factors: engine temperature, quality of the fuel mixture and valve position.
In this article we will analyze the mechanics of the process in detail so that you can confidently work with the tool in any conditions. Understanding the physical processes occurring in the cylinder during startup will help you avoid common mistakes that lead to “flooded” spark plugs or starter failure. Chainsaws Shtil They are famous for their reliability, but require adherence to a clear sequence of actions.
Before pulling the starter, you need to make sure that there is fresh fuel and that the main components are in good working order. Often the problem lies not in the engine itself, but in stale gasoline, which has lost its octane properties during a month of storage. Let's take a closer look at the preparation and the launch process itself.
There are two main startup scenarios, which differ radically in the algorithm of actions: cold startup and hot startup. Cold engine requires enrichment of the fuel mixture for first ignition, while a hot engine, on the contrary, needs to purge the cylinders from excess gasoline vapors. Ignoring this difference is the main reason why the saw will not start.
Preparing the instrument for the first launch
Before pulling the starter handle, it is necessary to visually inspect and prepare the fuel system. Make sure the chain is tight and chain brake unlocked, although on some models this does not affect startup, but is a safety rule. Check the oil level in the chain lube reservoir and whether there is fresh mixture in the tank.
Pay special attention to the quality of the fuel mixture. For two-stroke engines Stihl it is necessary to use high-octane gasoline (AI-92 or AI-95) and special synthetic oil with JASO FB or FC approval. The mixing ratio is usually 1:50 (20 ml of oil per 1 liter of gasoline), unless otherwise indicated by the manufacturer.
Use only fresh fuel mixture. Gasoline left in a canister for more than 2-3 weeks loses its properties and can lead to difficult starting or damage to the piston group.
If you are using the saw after a long period of storage, you may need to purge the fuel hose or check the filter. The air filter must also be clean: a filter clogged with sawdust will block the air flow, making the mixture too rich.
⚠️ Attention: Never leave a saw filled with fuel indoors or in a car in the sun. Gasoline vapors can create excess pressure in the tank, which will lead to difficult starting due to an over-rich mixture.
Cold engine starting algorithm
Starting a cold engine is the most crucial moment, requiring precise adherence to the sequence. Place the saw on a flat, hard surface. Make sure that the cutting attachment does not touch the ground, rocks or other objects that could prevent the chain from rotating.
Turn on chain brake, moving the front handle forward until it clicks. This is a mandatory safety requirement and will prevent the chain from turning if you accidentally press the gas during startup. On many models Stihl MS this will also unlock the throttle.
☑️ Checklist before the starter jerk
Now you need to close the air damper. To do this, the throttle control lever is moved to the cold start position (usually the highest position). On models with combination lever Master Control Lever this is done in one motion. If your model has a decompression valve, be sure to press it - this will reduce compression and make the first pull easier.
Grasp the front handle with your left hand and press the saw to the ground by stepping on the rear handle with your right foot (or resting your toe on the rear handle). With your right hand, gently pull the starter handle until you feel resistance, and then make a sharp, powerful jerk. Do not pull the handle all the way or release it abruptly - this may damage the mechanism.
As soon as the engine “seizes” (makes the characteristic sound of the first flash), immediately move the choke to the position half open (middle position). Cock the starter again. The engine should start. Immediately press the gas trigger and release it - the throttle will move to the operating position and the engine will idle.
Starting a warm chainsaw
The situation when you need to restart a saw that has just been running (for example, after changing a bar or a short break) requires a completely different approach. The engine is already warmed up and does not need to enrich the mixture. If you repeat the cold start algorithm, you will flood the spark plug.
For a hot start, the air damper must remain open. Move the throttle control to the "hot start" position (or simply apply the chain brake if the model is simple). There is no need to press the decompression valve, since the compression in a hot cylinder is already lower.
Why is it difficult to start a hot saw?
If the hot saw does not start with the throttle open, the mixture may be over-rich. In this case, you need to unscrew the spark plug, dry the cylinder with several jerks of the starter with the throttle open, and screw the spark plug back in.
Make several confident jerks with the starter. Usually chainsaw Shtil starts 1-3 times. If the engine does not start after 5-6 jerks, it may have cooled down, and then you should try the cold start algorithm, but without fanaticism with closing the damper.
Therefore, jerks should be energetic but controlled. If the saw is equipped with a system ElastoStart, it itself will absorb shock loads on the hand.
Typical startup errors and their consequences
Violation of starting technology is the main cause of breakdown of the starter system and failure of the piston group. The most common mistake is “over-tightening” the starter. When the engine has already seized, but the user continues to pull the handle without moving the throttle, re-enrichment occurs.
Another mistake is starting the saw by hand while holding it in the air. This is not only unsafe, but also ineffective: part of the jerk energy is spent on rocking the heavy body, and not on cranking the crankshaft. Always place the saw on the ground with your foot on the handle.
| Error | Consequence | How to fix |
|---|---|---|
| Starting with the chain brake closed | Overheating of the clutch and open circuit | Always apply the brake before starting |
| Long time idling | Soot on the spark plug, coking of the muffler | Warm up for no more than 10-15 seconds |
| A sharp jerk all the way | Starter cable break | Pull smoothly until there is resistance, then sharply |
| Using pure gasoline | Piston scuffing, engine wedge | Drain the fuel, add oil as required |
Diagnosing startup problems
If all manipulations are performed correctly, but the engine is silent, it is necessary to carry out diagnostics. First, remove the spark plug. Her appearance will say a lot. A dry spark plug indicates problems with the fuel supply (carburetor, filter, fuel pump).
A wet, black plug in the oil indicates an over-enrichment of the mixture or an imbalance in the proportion of oil in gasoline. In this case, you need to dry the spark plug, blow out the cylinder and try to start the saw again. If the spark plug has light brown soot, everything is fine with the engine; look for a problem in the ignition or compression system.
Check for spark. Place the spark plug on the metal (cylinder) and pull the starter. The spark should be bright blue and pierce the gap with a characteristic click. A weak or absent spark requires replacing the spark plug or checking the ignition coil.
⚠️ Attention: When checking for spark, hold the spark plug by the threaded part or use insulated pliers. High voltage discharge can be dangerous, although the current is small, but the shock can cause reflexive movement and injury.
Starting system maintenance for a confident start
Regular maintenance ensures that the question “how to properly start a Stihl chainsaw” will not arise every morning. Clean the cylinder cooling fins from dust and chips - overheating reduces power and makes starting difficult. Change the fuel filter at least once a season.
Monitor the condition of the starter rope. If it begins to fray or jam, disassemble the starter, wash the mechanism and lubricate the crankshaft bearing (if the design allows) or the ratchet axle. Lubrication must be heat resistant.
Regularly replacing the air filter and using a fresh fuel mixture eliminates 90% of problems with starting a chainsaw.
Don't forget about the fuel tank breather. This small hole in the tank cap equalizes the pressure. If it becomes clogged, a vacuum will form in the tank and gasoline will stop flowing into the carburetor. Clean it with a fine needle every time you refill.
What to do if the saw starts and immediately stalls?
Most often the problem is in the carburetor settings or air leaks. Check the tightness of the carburetor to the cylinder (cuff). Try enriching the mixture a little with a screw L (Low), but no more than 1/4 turn. Also check the fuel filter in the tank - if it is clogged, the saw will only work on the remaining fuel in the carburetor.
Is it possible to start a Stihl saw in winter?
Yes, you can, but preheating is required. Bring the saw into a warm room for 10-15 minutes before use. The fuel mixture should be fresh, with a slightly higher oil content (if the manufacturer allows it) or use winter additives. You need to start it in a place protected from the wind so that the spark and heat do not blow away.
How often should you change your spark plug?
Standard candle life NGK or Bosch for chainsaws is about 100 operating hours. However, its condition must be visually assessed every 20-30 hours of operation. If the electrodes are melted or carbon deposits cannot be cleaned off, replace them immediately.