Insufficient power and the failure of the saw chain to enter the wood when you press the trigger of gas is a direct sign that the chainsaw Stihl MS 180 does not develop the necessary engine speeds. Most often, the problem lies in the violation of the proportions of the fuel mixture, clogging of the carburetor or critical pollution of the exhaust system, which requires immediate intervention. Ignoring the symptom leads to overheating of the piston group and failure of expensive nodes, so the primary diagnosis should be carried out immediately after the detection of "failures" of thrust.
The main reason for loss of power in two-stroke engines Stihl is a violation of the process of mixing or exhaust gases. When the engine does not gain maximum speed, it operates in enriched or, conversely, too poor mode, which does not allow to reach the passport power of 1.5 kW. Owners often mistakenly believe that the problem is spark plug, but in 80% of cases the root of the evil lies deeper - in the fuel channels or mechanical damage seals.
Timely detection of malfunction allows to avoid major repairs of the cylinder-piston group. If you notice that the tool stalls under load or smokes, you need to consistently check all nodes of the fuel supply and gas distribution system. Below is a detailed algorithm for finding and eliminating defects specific to the model. MS 180.
Quality check of fuel mixture and filtration
The first step in the diagnosis is to analyze the composition of the fuel, because chainsaw Stile 180 It is extremely sensitive to the quality of oil and the octane number of gasoline. Using old fuel that has been in the canister for more than two weeks leads to the dissection of the mixture and loss of lubricating properties, which directly affects the power. The octane number of gasoline should not be lower than AI-92, and a special two-stroke oil should meet the standard. JASO FB/FC or ISO EGB.
The second critical element is the fuel filter located inside the tank. If the grid is clogged with resinous deposits or debris, gasoline does not enter the carburetor in sufficient volume, and the engine “choked” at high revs. The check is carried out by extracting the hose from the tank: the fuel should flow out in a smooth, pulsating stream when the tool is swaying. Sluggish dripping indicates the need to replace the filter or clean the fuel line.
⚠️ Attention: Never use pure gasoline without adding oil. The lack of lubrication in the mixture will lead to piston bullies and engine wedges in a few minutes of operation.
Also, it is worth paying attention to the condition of the air filter, which, with severe pollution, limits the flow of air. In the model MS 180 A simple felt filter is installed, which can be easily removed without tools. If it is soaked in oil or clogged with sawdust, the engine will run on a re-enriched mixture, which causes the soak on the candle and a drop in revolutions.
- 🛢️ Use only fresh fuel mixture prepared no earlier than 2 weeks ago.
- 🧹 Rinse the air filter regularly in soapy water and dry thoroughly before installation.
- ⛽ Keep the fuel tank cover tight to avoid vacuuming.
- 🔍 Check the condition of the fuel hose for cracks and cracks.
Diagnostics and adjustment of the carburetor
If the fuel system is in order, the next step is to check the fuel. carburettorThe one responsible for preparing the working mixture. Chainsaws. Stihl MS 180 often fails membrane node or clogged chiclera. The membrane loses elasticity over time, cracks or stretches, which disrupts the process of supplying fuel to the combustion chamber. To check, it is necessary to remove the lid of the carburetor and inspect the integrity of the membrane and needle.
Clogging of jellyplants is a common problem when using poor-quality gasoline or storing tools with residues of fuel. Small particles of resin block the channels, and the engine stops developing revolutions. Washing the carburetor in an ultrasonic bath or special solution often returns the tool to work. It is important not to use a metal brush for cleaning, which can damage calibrated holes.
Carburetor adjustment screws
Technically, the Zama C1Q-S68E carburetor installed on the MS 180 has only one idling adjustment screw (LA). The mix quality screws (H and L) are filled with plastic and are not designed for user adjustment. Attempting to drill them can lead to the inability to set up a saw without professional equipment.
After cleaning or replacing parts, idling speeds may be required. Vint LA allows you to set the minimum stable speed of rotation of the crankshaft, at which the chain does not move. If the screw fails to achieve stable operation, then the system has an air sucker or the carburetor fuel pump itself is faulty.
☑️ Checklist of carburetor checklist
Problems with the muffler and exhaust system
One of the most common reasons why chainsaw It dies under load and does not gain power, is a banal coking of the muffler. In the process of working on the walls of the exhaust channel and in the catalyst (if any), soak is deposited, which narrows the passage section. Exhaust gases cannot escape freely, back pressure is created, and the engine “strangles” itself.
To eliminate the malfunction, it is necessary to dismantle the muffler and carry out its mechanical cleaning. In the model Stihl 180 The muffler is attached with two nuts to the cylinder. After removal, you can burn the coar with a blowtorch lamp or gently clean it with a metal brush, trying not to damage the internal partitions. If the muffler has through burnouts, it must be replaced, since repair is impossible.
| Symptoms. | Possible cause in the silencer | Elimination method |
|---|---|---|
| Power drop | Narrowing of the outlet with garlic | Mechanical brush cleaning |
| Overheating of the engine | Complete exhaust lockdown | Burning of the lamp with the lamp |
| Cotton in a silencer | Violation of the tightness of the joint | Replacement of a gasket or stud |
| Vibration is strong. | Destruction of the internal grid | Replacement of muffler assembly |
Also check the condition of the gasket between the cylinder and the silencer: its damage will lead to air suction and engine malfunction.
Search for air sucker and check of cods
Suction of foreign air is an insidious malfunction that often goes unnoticed. If the engine gets excess air through leaky connections, the fuel mixture becomes too much. poorThis causes overheating and loss of power. The main places of check: the joint of the carburetor and the cylinder, the crankshaft glands and the gasket under the muffler.
For diagnosis, you can use the method of spraying the working engine with a flammable liquid (for example, a carburetor cleaner) in the places of the proposed sucker. If the engine speed changes (grow or fall), then the tightness is broken in this place. Pay special attention to the boulders of the crankshaft: their wear leads not only to the sucker, but also to the release of oil, which is noticeable by the characteristic undertone.
⚠️ Attention: The operation of the saw with air sucking is strictly prohibited. The poor mixture causes the piston to overheat instantly and can lead to bullying and engine jamming.
Often the problem lies in a cracked carburetor insulator or weakened fasteners nuts. Vibration when working gradually unwinds the connections, so regular stretching of the fastener is a mandatory maintenance procedure. If a crack is found in the plastic of the carburetor or insulator, the part should only be replaced.
Condition of spark plugs and electricians
Although the ignition system fails less often than the fuel one, this factor cannot be excluded. Color of tan on a candle It is the best indicator of the processes that occur inside the cylinder. If the candle is black and wet – the mixture is overenriched, if white and with a melted electrode – the mixture is too poor or there are problems with cooling.
Check the gap between the candle electrodes, which should be 0.5 mm. Too large a gap makes it difficult to spark at high speeds, and the engine begins to "trouble" or stall. Also inspect the high-voltage wire: it should sit tightly in the cap, and the cap itself should not have cracks through which the spark can punch through the mass.
- 🔌 Check the reliability of the contact of the candle cap and wire.
- 🕯️ Clean the candle electrodes from the soda with a brush or replace the candle with a new one.
- ⚡ Make sure the ignition coil (module) is in good working order if the spark is weak or absent.
- 🌡️ Control the color of the candle insulator to assess the quality of the mixture.
Mechanical malfunctions and CPG wear
If all of the above systems are serviceable, and the saw still does not develop turns, it is possible that mechanical wear of the cylinder-piston group (CPG) takes place. Bullying on the piston, wear of the rings or loss of compression do not allow you to create the necessary pressure for effective combustion of fuel. The compression check is performed by a compressometer: the normal value for Stihl MS 180 It is considered to be 8-12 atmospheres.
An indirect sign of CPG wear is difficult start and unstable operation even at idle speeds. If the compression is below 6 atmospheres, the engine can start, but will only work at low revs, stall when adding gas. In this case, a defect in the cylinder and piston is required, it may be necessary to plough or replace the entire assembly.
It is also worth checking the bearings of the crankshaft. Luft in bearings leads to the beating of the shaft and violation of the tightness of the ossels, which ultimately affects the power. Replacement of bearings requires a special detacher and skill, so it is better to entrust such work to specialists of the service center.
Expert advice: Before disassembling the engine, always blow the saw with compressed air. Getting even a small grain of sand inside the cylinder during assembly is guaranteed to lead to bullying and rapid failure of the new piston.
Main conclusion: In 90% of cases, the problem with the revs is solved by cleaning the carburetor, replacing the fuel filter and cleaning the muffler. Do not rush to disassemble the engine, start with the maintenance of the fuel system.
Why does the saw start, but immediately dies when pressed on the gas?
This is a classic sign of clogging of the fuel filter in the tank or violation of the ventilation of the tank. It is also possible that the idle channel in the carburetor is working, and the main jikler is clogged. Check the tank cover: try to unscrew it and start the saw. If the problem has disappeared, then the drainage hole in the lid is clogged.
Can I increase the power of the Stihl MS 180 tuning?
Theoretically, you can, having wasted the cylinder or replacing the carburetor with a more productive one, but for a household saw it is economically impractical. The engine’s resource will be significantly reduced and reliability will fall. It is better to maintain the normal state of the nodes.
How often should the fuel filter be changed?
It is recommended to change the fuel filter Stihl once a year or every 50 motor hours. If you use a saw infrequently, change the filter along with the fuel hose at each start of the season, as the rubber blubbers and cracks over time.
What if the saw does not develop after winter?
Most likely, over the summer, the light fraction of gasoline evaporated, and the carburetor remained resinous mass. It is necessary to completely drain the old fuel, remove and rinse the carburetor, replace the fuel filter and pour fresh mixture. Idle adjustment is often required after downtime.