Any tool can break and chainsaws Stihl MS 180 is no exception. Today we will try to understand such issues as to why the chainsaw stalls with increasing speed, also at idle and at full speed. Consider options for diagnostics and troubleshooting related to this behavior chainsaw Stihl 180.
Why chainsaw stalls when you press the gas?
Suppose a chainsaw runs typically at idle, but with a sharp pressure on the gas stalls. What could be the reason? Immediately the point is not in the ignition (no spark) since the instrument would not start if there was a malfunction of the fire and no flash. So there remains the fuel system.
There are a lot of malfunctions in the fuel system and to determine the exact reason why the Stihl 180 chainsaw stalls when you press the gas, it is necessary to carry out its full diagnostics. We recommend reading about common problems chainsaws Stihl 180 and their elimination.
The first thing to check is the fuel filter.
In some cases, a filter clogged with dirt is unable to pass through the fuel mixture in sufficient quantities. Accordingly, there is a shortage of fuel in the system, which leads to the fact that when you press the gas on the chainsaw, the fuel burns, and the new one does not have enough time to act as a result of which the Stihl chainsaw stalls. Also, when the fuel filter is clogged, there may be a noticeable drop in power of the chainsaw at maximum speed, but this is with minor pollution.
On the pages of the world wide web, you can find information that the Stihl 180 chainsaw may stall due to heavy air filter pollution. I want to refute this not quite correct information and report that the Stihl MS 180 carburetor is equipped with a compensator, which is designed and installed to take in the air necessary for the normal operation of the Stihl 180 chainsaw, bypassing the dirty air filter. Of course, the power with a clogged air filter will drop a little, but it definitely will not stall. Even the power may fall due to piston wear, repair of a Stihl MS 180 piston chainsaw is already required.
One of the reasons why the chainsaw does not develop momentum when you press the gas, and vice versa stall, this is a failure of the carburetor. Suppose saw Stihl 180 worked properly, and then it was put on for a long time and did not use it. After it was brought, and at idle, it works well, and when you press on the gas may stall. Why stalls? The reason is stuck in the valve carburetor nozzle. Of course, this is not 100%, but the probability of such a malfunction is high. We recommend reading the article about the device and repair carburetor Stihl 180.
To check the nozzle, it is necessary to remove the carburetor and disassemble it. For removal, it is essential to unscrew the two nuts securing the air filter and carburetor, then remove the air filter and engine control lever, while disconnecting the throttle control rod from the carburetor. Next, you need to slightly pull the carburetor toward you, and disconnect the fuel supply hose.
It is necessary to remove the fuel hose as carefully as possible and to prepare a plug for it in advance since the fuel must go out of it.
After removing the carburetor, it must be purged and cleaned of dirt, only after that the carburetor can be unrolled.
It is necessary to unscrew the carburetor main chamber cover, and this is the one on which the compensator is installed on top. Further, using a bolt of 8 mm and a length of at least 50 mm. Beat out the valve.
Beating the valve is necessary by installing the carburetor on a wooden stand, this will ensure its protection against damage to the body.
After the nozzle is removed, it can be blown through with a compressor. The valve should pass air only in one direction, if you can freely blow the valve in both directions, then it is faulty, and you need to replace it with a new one. Assembling the chainsaw after the valve is repaired, it is necessary to respect the reverse sequence of disassembly.
You can see clearly how the carburetor is being repaired, or rather, how to knock the nozzle valve out of the carburetor body correctly, you can watch the video.
Another common reason why a saw may stall with increasing speed is air leakage into the carburetor. Check it is possible only with a unique tool, but it is worth noting that if preventive work with the carburetor has not been carried out for a long time, you can install a new set of gaskets in the carburetor. In some cases, it helps to solve the problem with its depressurization.
When disassembling the carburetor to replace the gaskets, you need to carefully examine its needle valve, press the rocker arm and check its lifting. Sometimes, especially after the Stihl chainsaw has stood for a long time with the fuel in the carburetor, the needle may burn to the body of the carburetor and not perform its functions. Put, the needle valve will not pass the fuel mixture. In this case, the saw will not work.
Why stalls at idle?
The first and most common cause of this failure is incorrect carburetor adjustment. You can adjust the idle speed by yourself; for this, you need to have a Stihl adjusting screwdriver, which is supplied with the unit. The adjustment hole is located on the right side of the Stihl 180 saw on the handle and is marked with “-” and “” symbols.
If the Stihl chainsaw doesn’t keep moving and stalls at idle, you can be almost 90% sure that it has a disturbance in the system of the fuel pump, as a rule, air leaks into the crankcase through the gasket or, more often, through the glands crankshaft. The air leakage reduces or completely stops the pulse, which is fed through special channels to the fuel pump chainsaw. As a result, the Stihl 180 chainsaw does not receive the required amount of fuel and stalls at idle.
To diagnose, you can use a special device called a vacuum gauge.
The second way to check the performance of the glands is to pour gasoline into the engine crankcase and look at them if the glands skip gas, which means they cannot provide normal pressure in the crankcase, which will make idling impossible. And when working at high speeds, with unpressurized seals, there is a possibility of jamming of the crankshaft bearings.
The algorithm for checking crankcase and glands Stihl 180 for tightness is as follows:
- The top cover is removed.
- The air filter housing and the carburetor are removed.
- Removes the handle chainsaw.
- Spin the starter and retracts.
- From the side opposite to the starter, the side cover and drive sprocket are removed.
- A piston stopper is installed in the candle hole, or a cord from an old starter with knots attached to it is stuffed into the cylinder.
- Turn off the flywheel and clutch, after which the parts are removed. It is worth knowing that the grip of the chainsaw has a left-hand thread and is unscrewed in a clockwise direction.
- Removed gear drive oil pump.
Having examined the Stihl MS 180 chainsaw, you can see the glands, and then you need to fill the crankcase with gasoline and check for leaks. Fill the crankcase. It is possible through the fuel window in the cylinder; for this purpose, the piston must be lifted to the maximum. If leaks are detected, it is necessary to replace defective seals or to reseal the pallet again. Collect Stihl 180 can be following the reverse sequence of the algorithm.
Why stalls at full speed?
Very often, you can hear the question of why chainsaw stalls at full speed. There may be several reasons. First, you need to consider exactly how the saw stalled. Suppose the tool worked normally and suddenly, for no apparent reason, stalled sharply and at the same time, the starter does not turn. In such a situation, you can be 100% sure that the chainsaw is jammed and you need to start overhauling it.
The second situation is when the Stihl 180 chainsaw worked normally, then gradually in a short time lost power and stalled, while there was an overheating of the cylinder. In this case, the most likely cause is air leakage under the rubber tube connecting the carburetor with the cylinder or its rupture. The mixture was depleted, resulting in overheating. You can eliminate the cause by changing the nozzle.
If the Stihl MS 180 chainsaw stalls at idle, does not gain power when you press the gas or even stalls at full speed, it is necessary to diagnose the fuel system and check the crankcase for tightness. You can do it yourself, but you must have certain skills. If you are not familiar with the push-pull saws, it is better to turn to experts, because this technique is rather capricious and any mistakes are costly.