The situation where the chainsaw Stihl MS 180 It is a candle that is familiar to many owners of this popular tool. Instead of sparking and igniting the mixture, you see a wet, black candle from the soak, and the engine refuses to start even after repeated attempts to jiggle the starter. This is a classic sign of re-enrichment of the fuel mixture, in which too much gasoline and not enough air enters the cylinder.
The problem can come on suddenly, even if the saw worked properly the day before. Most often this occurs after long attempts to start the tool or when stored in an unprepared state. Combustion chamber overflow blocks normal spark formation, making the launch impossible without a number of recovery procedures. Understanding the physics of the process will help to get the technique back into operation faster.
Do not panic or immediately carry the saw to the service, as in most cases the reason lies in simple settings or temporary factors. Two-stroke engine The 180 is extremely reliable, but requires proper handling of the fuel system. In this article, we will discuss in detail all possible causes of flooding (watering) and methods for their elimination.
The main reasons for the re-enrichment of the mixture
The fundamental reason why Chainsaw Stile 180 fills the candleIt is a violation of the proportion of mixing air and fuel. carburetor ZamaThe stain installed on this model is membrane and sensitive to changes in pressure and condition of the filter elements. If there is little air and a lot of gasoline, the mixture becomes “rich” and does not have time to burn, settling on the electrodes.
Often users themselves provoke the situation by abusing the lever of the sucker. With a cold start, the flap blocks the access of air, creating a vacuum, but if after the first flash not to transfer the lever to the working position, the engine will suffocate. It could also be a cause. air-filterIt does not physically allow the required amount of oxygen to burn normally.
⚠️ Warning: Never try to get a full saw with the air filter closed or with a fully open throttle – this will only aggravate the situation and fill the muffler.
Another factor is the quality of the fuel itself. Old benzo-oil mixture, which stood for more than two weeks, loses its properties and can cause malfunctions in the membranes of the carburetor. Heavy fractions settle, clogging channels and violating the dosage.
Diagnosis of the spark plug condition
The first step in troubleshooting should always be a visual inspection. Unscrew the candle with a special key and carefully examine it. The color of the soda will tell about the processes occurring inside the cylinder, more than any external signs. The normal color of the electrode is light brown or coffee.
If you see black, sticky soda and smell a strong smell of unburned gasoline, the diagnosis is confirmed. A wet candle means that the spark is either absent or too weak to penetrate the fuel layer. In some cases, electrodes may be observed. oilyThis indicates problems with the quality of the oil or its excess in the mixture.
Pay attention to the gap between the central and side electrode. For the model MS 180 It shall be 0.5 mm. Too large a gap will require stress for breakdown, which with a weak coil will lead to ignition misses. Too small a gap will give a weak spark, not enough to light a rich mixture.
- 🔴 Black wet coating: a sign of a clear overflow of fuel, the candle must be dried.
- ⚫ Dry black loam: indicates the work on the enriched mixture or poor quality of the oil.
- 🟤 Brick red: It indicates the presence of additives in gasoline or the engine at the temperature limit.
- ⚪ White or light plaque: a sign of working on a poor mixture, which is dangerous for overheating, but is not the cause of flooding.
Always have a new NGK BPMR7A or Bosch WR7DC candle in stock to replace the suspicious one and check the ignition system.
Algorithm of drying and starting the engine
If the diagnosis confirms that Chainsaw Stile 180 fills the candleIt is necessary to perform the procedure of drying the cylinder. This process requires patience and a clear sequence of actions. The main goal is to remove excess fuel from the combustion chamber and blow out the system.
First, twist the candle and wipe it with dry rags. The candle itself can be calcined over a gas burner or lighter for a few seconds to vaporize the remaining gasoline from the pores. Be careful: do not overheat the ceramic insulator abruptly, let it cool gradually.
While the candle is drying, the cylinder must be blown. To do this, insert an old candle or just leave the candle hole open (covering it with a clean cloth so that dust does not fly) and make 10-15 sharp jerks with the starter. This will create a powerful airflow that will blow gasoline vapors out of the cylinder and silencer.
☑️ Checklist for engine drying
After drying, collect everything back. Insert a dry candle, make sure the air damper is open (the lever at the bottom), and try to get a saw. If the engine catches but stalls, do not close the pump immediately. Let him work at high speeds to warm up and burn out the moisture residue.
| Candle condition | Probable cause | Action. |
|---|---|---|
| Wet, smells like gasoline. | Overflow at launch | Drying, cylinder purging |
| Black, dry, soot. | Rich mix at work | Cleaning the filter, adjusting the carburetor |
| Oily | Lots of oil in the mix | Fuel mix replacement |
| Wet but sparkling | Ignition problems | Checking the coil and clearance |
Adjustment of the carburetor and inspection of filters
If after drying the problem returns, then the regulation is violated carburettor. On the model. Stihl MS 180 Often there is a carburetor without a screw adjusting the quality of the mixture at low revs (screw L), however, the screw of high revs (H) and idling (LA) are available. Factory settings can get lost due to vibration or wear of the membranes.
Before any adjustment, be sure to replace or thoroughly blow the air filter. If the filter is full of sawdust, the engine will “suck” gasoline in excess, trying to compensate for the lack of air. Dirty filters are the most common reason why Chainsaw Stile 180 fills the candle When working under load.
Rotor adjustment H You should be careful. His turn counterclockwise enriches the mixture, clockwise - impoverishes. If the candle is pouring, try to twist the screw a little (deplete the mixture), but not more than 1/4 revolution. After each change, let’s work on the saw and check the color of the candle.
⚠️ Attention: The engine operation on too poor mixture (H screw twisted strongly) leads to overheating of the piston group and bullies. Be careful with the adjustments!
The secret of setting up the carburetor Stile 180
On many Zama carburetors installed on the MS 180, the L screw is hidden under a plastic plug or missing. This is done by the factory to protect against unskilled interference. If the saw is not pulling well and pouring, it is often easier to replace the carburetor entirely or to carry out membrane defects than to try to adjust the chicklers.
Fuel system and mixture quality
Fuel quality plays a critical role in the stability of the two-stroke engine. Use of pure gasoline AI-92 or AI-95 without alcohol and ethanol is mandatory. Alcohol-containing fuels are aggressive to rubber seals and can cause the mixture to dissect, resulting in pure oil or pure gasoline entering the cylinder.
The proportion of mixing oil and gasoline for Stihl MS 180 is 1:50 (20 ml of oil per 1 liter of gasoline) when using branded oil Stihl HP Ultra. If you use another oil, the ratio can be 1:40 or 1:33. The excess oil in the mixture is guaranteed to result in Chainsaw Stile 180 fills the candle It smokes.
Check the fuel filter in the tank. If it is clogged or damaged, it may pass fuel unevenly. Also check the fuel hoses for cracks. Suction of air through the cracked hose impoverishes the mixture, but if the crack is above the fuel level, the balancing of pressure in the tank may be disturbed.
- ⛽ Freshness of the mixture: Do not store the finished fuel for more than 2-3 weeks.
- 🧴 Type of oil: Use only oils for air-cooled two-stroke engines.
- 🌡️ Temperature: when storing a saw in the cold without draining fuel, the carburetor may work incorrectly.
The quality of the mixture and compliance with 1:50 ratios are more important than any adjustments to the carburetor. Bad fuel will ruin the work of even a perfectly tuned saw.
Prevention and proper operation
To the future chainsaw Stile 180 It does not cause problems with the launch, it is important to follow the rules of operation. Never leave a tool with a full tank for long-term storage. Gasoline evaporates, leaving a resinous plaque that clogs the carburetor's jellyfish.
The correct cold engine start algorithm: turn on the ignition, close the air valve (lever up), press the decompression valve (if any), make a 3-4 jerk starter before the first flash (or the sound of "sneezing"). Immediately after the flash, open the valve (lever down) and start in normal mode.
Regularly clean the area around the candle and silencer from sawdust. The coar in the muffler can also make it difficult for exhaust gases to escape, creating a back pressure that prevents the cylinder from filling normally with fresh mixture. Cleaning the muffler and exhaust windows is an important part of maintenance.
Watch the condition of the scallops. If they are worn out, excess air gets into the crankcase, which disrupts the work of the carburetor and can lead to unstable start and re-enrichment. Checking the oils is better carried out during capital maintenance.
What to do if the candle is dry, but the saw does not start?
If the candle is dry, then the fuel does not enter the cylinder. Check: the presence of fuel in the tank, the opening of the fuel crane (if any), the state of the fuel filter in the tank, the work of the fuel pump of the carburetor (membrane). It is also possible to clog the fuel supply channel in the carburetor.
How often should I change the candle to the Stihl MS 180?
The candle’s resource depends on the quality of the fuel and the load. On average, the candle is recommended to be changed once a season of active work or after 100 motor hours. However, if problems with the start check the condition of the candle should be carried out immediately.
Can I use a candle with a different potassium number?
The use of candles with an inappropriate potassium number (more "cold" or "hot") can lead to kalyl ignition or, conversely, fouling with soda. For MS 180 It is strictly recommended to use candles specified in the instructions (NGK BPMR7A or analogues).