Starting a gasoline powered tool such as Stihl MS 180, often seems like a simple matter, but this is where the main mistake of beginners lies. Incorrect sequence of actions or ignoring the position lock lever may result in the engine not starting the first time, and repeated attempts may cause the spark plug to burn out.
For a confident start, you need to clearly understand the difference between starting “cold” and “hot”. In the first case, an enriched mixture is required, in the second - a standard one. If you have just cut wood and the engine has been cooling for a few minutes, the procedure will be different from starting it after a long period of inactivity.
In this guide we will look at all the nuances, including the position decompression valve (if your modification has it) and correct operation of the gas trigger. Compliance with these rules will extend the life of the piston group and ensure stable operation of the tool.
Preparing the saw for the first start
Before pulling the starter, you need to make sure that the tool is assembled and ready for use. Chainsaw Shtil 180 Comes unassembled and initial assembly requires attention to detail. Install the guide bar and chain, making sure that the cutting teeth are facing in the correct direction - in the direction of travel from above.
Pay special attention to chain tension. A correctly tensioned chain should not sag from below, but at the same time it should be free to turn by hand. If the chain is overtightened, it will create excess crankshaft voltage, which will make it difficult for the starter to crank the engine and can damage the bearings.
⚠️ Attention: Never leave the chainsaw idling with a loose chain. Vibration can loosen the bar nuts, causing the chain to fly off and cause injury.
The next critical stage is preparing the fuel mixture. Two-stroke engines do not have a separate oil lubrication system, so it is added directly to the gasoline. Use only high octane gasoline (not lower than AI-92) and high-quality synthetic oil for two-stroke engines with the marking Stihl HP Ultra or analogue.
The mixing ratio for new Stihl saws is usually 1:50 (20 ml of oil per 1 liter of gasoline). Shake the mixture thoroughly in a separate canister before pouring into the tank. Do not store the finished mixture for more than a month, as it loses its properties and may coke the carburetor.
- ✅ Use only fresh gasoline, the shelf life of which does not exceed 2-3 weeks.
- ✅ Observe the exact dosage of oil using a measuring syringe or canister cap.
- ✅ Use special containers for mixing fuel with markings.
Starting a cold engine: step-by-step algorithm
Cold starting is the most common situation when the saw has been standing overnight or longer. In this case, the fuel from the carburetor may have evaporated, and a rich mixture is required to start. Place the saw on a flat, hard surface, making sure that the saw chain does not touch anything.
Press the decompression valve (if model equipped with a button Decomp). This will reduce compression in the cylinder, making the first pull of the starter easier. If there is no such button, just go to the next step. Move the throttle lock lever to the cold start position.
⚠️ Attention: The throttle lock lever has several positions. For a cold start, it must be raised up all the way, which corresponds to the position of the closed air damper.
Grasp the front handle with your left hand, pressing it to the ground. Step on the starter handle with your right foot. Pull the starter handle up sharply and firmly. Do not pull the cable all the way - this may damage the mechanism. After the first flash or seizure of the engine, wait a couple of seconds.
As soon as the engine “grabs”, move the lock lever to the middle position (half-open throttle). Pull the starter again. The engine should start. Immediately press and release the gas trigger - this will put the saw into idle mode.
☑️ Check before start
Starting a hot engine and restarting
A hot engine situation occurs when you take a break from work for 5-10 minutes. There are already fuel vapors in the carburetor and cylinder, so enriching the mixture is not required, but on the contrary, it can lead to pouring candles.
To start hot Stihl MS 180 algorithm is simpler. The throttle lock lever is moved to the middle position (between the extreme points). The decompression valve (if equipped) is also pressed. The gas trigger is not touched.
Pull the starter handle. The engine should start almost immediately. If this does not happen after 3-5 pulls, you may have overfilled the candle. In this case, unscrew the spark plug, wipe it with a dry cloth, blow out the cylinder, screw the spark plug back in and repeat the starting procedure as for a cold engine.
What to do if the saw does not start after a long period of inactivity?
If the chainsaw was left without fuel for several months, the membranes in the carburetor could dry out. Try pressing the primer several times (if you have one) or adding 10-15 ml of pure gasoline directly into the spark plug hole (after unscrewing the spark plug), then tighten the spark plug and start according to the instructions for a cold engine.
Table: Throttle Lock Lever Positions
Understanding how the locking lever works is the key to success. This element controls the carburetor choke. Below is a table explaining the functions of each position.
| Lever position | Damper condition | When to use |
|---|---|---|
| Upper (I) | Closed (maximum enrichment) | Starting a cold engine |
| Secondary (II) | Slightly open (working mixture) | Starting a hot engine, working |
| Lower (0) | Open (stop) | Engine stops (stalls) |
Do not attempt to start the saw if the lever is in the down position - this is the “Stop” position. Also, do not leave the lever in the up position after starting - the engine will run too rich, resulting in carbon deposits on the piston and loss of power.
Carburetor and idle adjustment
Sometimes proper startup does not guarantee stable operation. If the saw stalls when the gas is released or, conversely, the chain rotates at idle, adjustment is required. On Stihl MS 180 often a carburetor with one adjusting screw is installed LA (Low Air), responsible for idle speed.
Rotating the screw clockwise increases the speed, counterclockwise decreases it. Your task is to achieve a position in which the chain is motionless, but the engine does not stall when you sharply press the gas. If the chain spins, reduce the speed with the LA screw.
⚠️ Attention: The factory carburetor setting is optimal. Do not turn the mixture screws (H and L), if available, without a tachometer. This can lead to the engine running on a lean mixture and overheating the piston.
Check the idle speed only on a warm engine. Let the saw run for 2-3 minutes at medium speed, then release the gas. If the engine stalls, add a few more revolutions with the propeller. If the chain spins, turn it down.
If the idle speed screw is completely unscrewed and the chain is still spinning, it is possible that air is leaking into the carburetor through the seals or gaskets. A leak test is required.
Typical errors and troubleshooting
Even following the instructions, users may encounter problems. The most common of them is “overflow”. If you have made many jerks with the starter and the saw does not start, most likely the spark plug is wet. Unscrew it, wipe it, dry it and blow out the cylinder by pulling the starter 5-6 times without a spark plug.
Another problem is the lack of spark. Check the spark plug by applying its thread to the metal of the cylinder (without touching the electrode with your hands!) and pulling the starter. If there is no spark, replace the spark plug or check the high-voltage wire. It could also be due to a clogged fuel filter in the tank.
- 🔥 Check the air filter: a dirty filter blocks air flow, making the mixture too rich.
- 🔥 Inspect the muffler: carbon deposits in the spark arrester can choke the engine.
- 🔥 Make sure the fuel hoses are tight: cracks lead to air leaks.
Regular air filter maintenance will extend the life of your engine. Remove the filter cover after each tank of fuel, shake out the dust or wash the filter in soapy water (if it is synthetic) and dry. Never work without a filter.
Safety and final recommendations
Starting a chainsaw is a process that requires concentration. Always hold the saw firmly with your right foot on the starter handle. The left hand should securely hold the front handle. Never wrap the starter rope around your hand.
Work in personal protective equipment: glasses, gloves and headphones. Stihl MS 180 is a powerful tool, and chain kicking can happen at any second, especially when sawing with the tip of a bar. The rebound zone is the upper quarter of the tire nose.
The main secret to a long service life of the saw is a high-quality fuel mixture and a clean air filter. Saving on oil or working without a filter will kill the piston in one season.
By following these simple rules and algorithms, you will ensure a long service life for your chainsaw. Remember that regular inspection and proper storage (draining fuel for the winter) are more important than repairs after a breakdown.
Is it possible to start Stihl MS 180 without oil in gasoline?
Absolutely not. A two-stroke engine will burn out within a few minutes of running without oil in the mixture. The oil lubricates the crankshaft bearings and piston group. Working “on pure gasoline” will lead to piston scuffing and major repairs.
Why does the saw start and immediately stall?
The most common cause is a clogged fuel filter, air filter or carburetor. It is also possible that water may get into the fuel tank or the crankshaft seals may leak (air leaks).
What gasoline is best to use for Shtil 180?
We recommend AI-92 or AI-95 gasoline from proven gas stations. Avoid using fuel with an octane rating below 90 as this may cause engine detonation and overheating.