Owners of garden equipment often face a situation where, after winter storage, their favorite tool refuses to work. Chainsaw Stihl MS 180 is no exception: despite German reliability, it is sensitive to the quality of the fuel mixture and storage conditions. An attempt to start the engine head-on without preliminary preparation can lead to serious damage or, at best, a waste of time and nerves.
The main problem lies in the properties gasoline-oil mixture, which, when left standing for a long time, delaminates, and the gasoline evaporates, leaving a tarry residue. It is this deposit that clogs the carburetor jets and damages the fuel pump. To avoid costly repairs, it is necessary to clearly understand the physics of the process and the sequence of actions when resuscitating an instrument.
In this article we will analyze a step-by-step algorithm of actions that will help revive your Calm 180 even after several months of inactivity. We will look at common mistakes, methods for checking ignition and fuel supply systems, and also give recommendations for prevention. The right approach will allow you to save on service costs and extend the life of the unit.
Diagnosis of the fuel system condition
The first step before any manipulation of launches should be a visual and tactile assessment of the current condition of the instrument. If there is old mixture left in the tank, it absolutely cannot be used for starting attempts. Old gasoline loses its octane properties and turns into an aggressive substance that can damage carburetor membranes.
It is necessary to completely drain the remaining liquid from the tank. To do this, turn the saw over, substituting the container, and press the primer several times (if your modification has one) or simply let the fuel flow out by gravity. After this, it is important to evaluate the smell: if it is sharp and unpleasant, it means that oxidation processes have occurred.
Next, you should check the condition of the fuel filter. In the model Stihl MS 180 it is located inside the tank at the end of the fuel hose. If the filter is blackened or covered with a sticky coating, it must be replaced. A clogged filter will create a vacuum in the tank, and fuel will simply stop flowing into the carburetor.
⚠️ Attention: Never try to start the saw with an old fuel mixture, even adding fresh gasoline. The concentration of oil breakdown products is too high and is guaranteed to lead to coking of the piston group.
Check the integrity of the fuel hoses. Over time, rubber hardens and cracks, which leads to air leaks. Air leak - this is one of the main reasons why the saw does not start or stalls at idle. Visually inspect the hose for microcracks, especially at bends.
Preparation of fresh working mixture
Proper fuel preparation is critical to successful restarting after a period of inactivity. Chainsaws Shtil require the use of high-octane gasoline (not lower than AI-92, and better than AI-95) and special two-stroke oil. The mixing ratio for new saws and saws after disuse must be strictly observed.
Use the included measuring cup or precision syringes. For a ratio of 1:50 (standard for Stihl HP Ultra oils) 20 ml of oil is required per 1 liter of gasoline. If you are using oil from another manufacturer, carefully read the instructions on the bottle, as the concentration of additives may differ.
Use only fresh gasoline purchased no more than 2 weeks ago. Fuel that has been sitting in a canister for six months has already lost some of its properties and may contain water from condensation.
Shake the container with the mixture immediately before pouring it into the tank. Oil is heavier than gasoline and tends to settle to the bottom. Mixture homogeneity - the key to proper engine lubrication. If you fill in pure gasoline first and then oil, the engine may seize due to oil starvation.
Pour the prepared mixture into the tank. Do not fill the tank to the brim; leave about 1-2 cm to the neck for the formation of a fuel parasite. Close the lid tightly until you hear a characteristic click. The system is now ready for initial pumping.
Engine cold start algorithm
Startup procedure Stihl MS 180 after downtime has its own characteristics. The standard “cold start” algorithm is best suited here, but requires strict adherence to the sequence of actions. First, place the saw on a level, hard surface, making sure the saw chain does not touch the ground or objects.
Activate the decompression valve (if your modification has one, although the MS 180 often does not, so move on to the next step). Move the throttle control to the cold start position. On the MS 180 this is done by pulling the damper control handle towards you as far as it will go.
☑️ Checklist before the starter jerk
Grasp the front handle with your left hand, holding the saw to the ground. With your right foot, step on the rear handle stop. Pull the starter cord upward with a sharp and strong jerk. Do not pull the cord all the way to avoid breaking it. The engine should make the first "grabbing" sound.
As soon as the first pop is heard, immediately move the damper lever to the “open” (working) position. Do 1-2 more jerks. The engine should start. Let it warm up at idle for 30-60 seconds before starting work.
⚠️ Attention: If after 5-7 jerks the engine does not show signs of life, do not continue to pull the starter. This will overheat the ignition coil and drain the battery (if electronics are present) or simply damage the starter mechanism.
Checking the ignition system and spark plugs
If the fuel system is fine and the saw won't start, the next suspect is ignition system. In 80% of cases of starting problems after winter, the spark plug is to blame. It may be filled with fuel, covered with carbon deposits, or simply fail.
Unscrew the spark plug with a special wrench. Carefully inspect its electrode. If it is wet and smells of gasoline, it means the mixture is over-rich or there is no spark. A dry spark plug indicates that fuel is not entering the cylinder. The normal color of the electrode is light brown or brick.
Check for spark. Place the cap of the high-voltage wire on the spark plug, press the threaded part of the spark plug to the metal part of the cylinder (ground) and pull the starter. The spark should be bright, blue and jump between the electrodes. A dull red spark or its absence indicates a problem.
What to do if there is no spark?
If there is no spark, check the spark plug cap - the contact group inside it may have oxidized. The ignition coil itself (magneto) or the electronic ignition module could also fail. In forest conditions, you can try heating the candle with a lighter to evaporate the gasoline, but this is a temporary measure.
Spark plug gap Stihl MS 180 should be 0.5 mm. If it is knocked down, it can be carefully corrected, but it is better to replace the spark plug with a new one, since it is a consumable item. Use only models recommended by the manufacturer, for example NGK BPMR7A.
Carburetor adjustment after inactivity
Often, after long-term storage, the factory carburetor settings are lost due to drying out of the membranes or changes in fuel density. On the carburetor Walbro or Zama, which are installed on the Stihl 180, there are usually two or three adjustment screws: L (low speed), H (high speed) and T or LA (idle speed).
For initial startup after inactivity, it is better to return screws L and H to the factory position. To do this, carefully (without fanaticism) screw them all the way, and then unscrew them back. Screw L is usually unscrewed by 1-1.5 turns, screw H by 1 turn. This is the basic setup to get started.
| Parameter | Meaning | Impact on work |
|---|---|---|
| Screw L | 1.0 - 1.5 turns | Responsible for traction at low speeds and acceleration |
| Screw H | 1.0 revolution | Adjusts maximum power and speed |
| Screw T (LA) | Individually | Stabilizes idle speed, the chain should not spin |
| Spark plug gap | 0.5 mm | Spark quality |
If the saw starts but stalls when gas is added, the mixture is too lean (too much air). You need to tighten screw L a little. If, on the contrary, it smokes and “chokes,” the mixture is rich, screw L needs to be unscrewed. Carburetor settings - the process is delicate, requiring a tachometer for an ideal result, but “by ear” is also possible.
Basic carburetor adjustment allows the engine to start, but for full operation under load, final adjustment with screw H using the tachometer is desirable.
Typical faults and methods for their elimination
Even after all the procedures, the saw may behave strangely. Let's look at the main symptoms and their causes. If the engine starts and immediately stalls, the fuel filter in the tank or the tank breather is most likely clogged. The breather is a small valve in the tank cap that equalizes pressure. Clean it with a fine needle.
If black smoke is coming from the muffler and you hear a crackling sound, the exhaust system may be clogged. On Stihl MS 180 There is a spark arrestor, which over time becomes overgrown with carbon deposits. It must be removed and burned with a torch or soaked in a solvent.
Another common problem is a leak in the crankshaft seals. If the seal is dry, it begins to suck in air and the mixture becomes lean. You can check this by applying pressure to the crankcase and immersing the engine in water (bubbles will indicate a leak) or by treating the joints with WD-40 while the engine is running (the speed will change).
⚠️ Attention: Working with open flames or solvents near the chainsaw is prohibited! Dismantle the muffler and burn off carbon deposits only away from flammable liquids.
If the starter turns too easily, as if there is no compression, the piston rings may be stuck. Try pouring 2-3 cubes of two-stroke engine mixture into the spark plug hole and leave for several hours. This may help the rings move.
Prevention and proper storage
So that the question “how to start a chainsaw” does not arise every spring, it is necessary to properly prepare the tool for wintering. Main rule: store the saw with used fuel. After the end of the season, let the engine run until it stalls due to lack of mixture. This ensures that there is no gasoline left in the carburetor to turn to tar.
Clean the saw from sawdust, dust and dirt. Lubricate the saw bar and chain with special oil, and wipe the body with a damp cloth. Store the tool in a dry place, upright or hanging, to avoid deformation of the tires.
Do I need to remove the chain for the winter?
Experts recommend loosening the chain tension during long-term storage, since the metal of the tire and chain can expand/contract due to temperature changes, which will lead to a loss of elasticity. It is not necessary to remove it completely if the saw is hanging.
Run the saw regularly, once a month during the season, even if you do not plan to saw. This will lubricate the internal parts with fresh oil and prevent the bearings from souring. Following these simple rules will ensure your Stihl MS 180 long and trouble-free service.
Is it possible to use AI-92 motor gasoline instead of AI-95?
Technically, it is possible if the octane number meets the manufacturer’s requirements (usually not lower than 90-92). However, AI-95 is more stable and contains fewer impurities, which is critical for two-stroke engines with a high compression ratio. The use of AI-92 is acceptable, but it reduces engine life.
Why does the saw smoke white smoke after starting?
White smoke is burning oil. After downtime or when starting for the first time with a new spark plug, this is normal. If the smoke persists (does not go away) after warming up, the mixture ratio may be incorrect (too much oil) or the piston rings may be worn and oil is entering the combustion chamber directly.
How often should the fuel filter be changed?
The fuel filter is a consumable item. It is recommended to change it once a season or every time you change fuel hoses. If the filter turns black ahead of time, this is a signal of poor quality fuel or oil.
What to do if the starter cord breaks?
Do not try to start the saw by wrapping the cord around your hand or using foreign objects - this can cause injury. It is necessary to disassemble the starter housing, remove the old cord, wind a new one (diameter and length strictly according to the original) and charge the spring. The procedure requires care.
Is it possible to store a chainsaw in the garage in winter?
Yes, you can, but only in a heated or dry unheated garage. The main thing is the absence of condensation. Sudden temperature changes in an unheated area can cause moisture to form inside the engine, causing corrosion. It is better to store it in the house or pantry.