Why does a lawn mower stall when you gas

Why does the car stall on gas? Let’s figure it out!

Often on various forums and in the comments to articles about LPG, you can find questions such as: the car stalls on gas, what to do if the car stalls on gas at idle, and so on. The problem is common, since gas equipment is not always set up or maintained correctly and in a timely manner.

As a result, when switching to gas fuel, the engine stalls. The situation is unpleasant and can promise many problems related to the search, diagnostics, etc. However, if you know where to look, and I will give you a direction, then the process can be accelerated.

Lawn mower won’t start after winter? Old fuel flush!

A very common problem when LPG stalls at idle, that is, the engine runs at idle on gas fuel and after a while or immediately stalls.

In this case, the cause should be looked for in the following places

First of all, you should check the heating of the gearbox; often, due to poor heating, the engine switches to gas and stalls. It is often found when HBO is installed with violations, the heating of the gearbox is done from the throttle valve, and not from the heater stove, as it should be. Also, sometimes unfortunate installers put thin cooling pipes, which, as a result, are not able to ensure normal circulation of coolant through the system. The heating of the gearbox must be connected in parallel with the stove, otherwise you may have such problems. Among other things, check the coolant level, it may be too low, as a result of which the antifreeze does not circulate as it should.

Increased pressure in the reducer. Due to excessive pressure in the line due to the fault of the gas reducer, problems may arise with the engine idling. To solve the problem, adjust the pressure by lowering it to the required level, then check if the problem is gone.

Condensate in the gas. In the cold season, gas fuel can contain a lot of condensate (water particles), which at low temperatures can freeze, preventing the gearbox and injectors from working properly. The latter may simply not open due to condensation.

If the car stalls on gas at idle, it may be necessary to adjust these same idles. On gasoline, everything is done by the IAC, but on gas, you can adjust the idle speed using the adjusting screw on the gearbox.

Check the condition of the diaphragms of the reducer, possibly they should be replaced How to repair a gas reducer read here and here.

Filters. During operation on gas, the car stalls also due to the banal contamination of coarse and fine filters. Everything is very simple here, the filter is clogged, gas does not flow, the engine stalls with gas, and not only at idle.

Air leaks. If there is a leak in the system, for example, at the joints or the clamps are loosened, then you cannot avoid problems with working on gas fuel. over, if everything is ok when the accelerator pedal is pressed, then when it is released, there is little fuel, the fuel assembly becomes “poor” and the engine often stalls on gas at idle.

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Injectors. A strong blockage can lead to unstable operation of the motor, up to a complete stop. In this case, the gas injectors should be flushed, replaced parts that are worn out, provided that the injectors are collapsible. After that, calibrate the injectors and reinstall them.

Throttle body and IAC. If all of the above is in order, check the condition of the throttle valve as well as the idle speed control (IAC).

If, after a long search, you still did not manage to understand why the car stalls on gas, I recommend visiting a qualified specialist and tell him about your problem and observations in as much detail as possible.

That’s all for me, write in the comments what reasons associated with this problem are known to you. Share your experience, maybe your experience will help someone solve his problem.

Why does the chainsaw stall when you press the gas

Let’s say the chainsaw works normally at idle, but when the gas is pressed sharply, it stalls. What could be the reason? It is immediately clear that this is not about the ignition (no spark), since if the ignition is faulty and there is no spark, the tool would simply not start. This means that the fuel system remains.

There are a lot of malfunctions of the fuel system and to determine the exact reason why the Stihl 180 chainsaw stalls when you press the gas, you need to carry out a complete diagnosis. We recommend reading about common malfunctions of the Stihl 180 chainsaw and their elimination.

If the Stihl MC 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 leaks. You can do it yourself, but you need to have certain skills. If you are not familiar with two-stroke saws, it is better to turn to specialists, since this technique is rather capricious and any mistakes are expensive.

Why does the chainsaw stall when you press the gas?

Hello! If you find yourself on this web page, then, most likely, your chainsaw stalls when you press the gas, and you want to find out why this is happening and what to do about it. That all the same, I will try to provide any assistance to you in this dilemma, having analyzed the more widespread prerequisites for such a hassle, and similarly ways to eliminate them.

At the beginning, I will immediately write for novice users that some chainsaws, before the start of the working day, require the engine to warm up at idle speed for about one minute. While the engine is cold, the saw may stall when gas is added.

What is needed if a heated chainsaw is idling, but stalls under load, this means that:

  • the carburetor is incorrectly configured or clogged. the most common case;
  • it lacks air, the consumption of which increases sharply with increasing speed. this means that the air filter is dirty (the rarest case, because the filter is contaminated evenly, so the user first notices a loss of power);
  • it does not have enough fuel, the consumption of which also increases with increasing speed. this means that the fuel filter is dirty (also an infrequent case);
  • and the worst case, if there is excessive friction between the piston and the cylinder wall, associated with a lack of oil in the fuel consistency. after such a chainsaw operation, you will most likely fly into the repair of the piston group, because scuffs form on the piston and cylinder walls that impede operation saws.
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One of the reasons why the chainsaw does not develop speed when you press the gas, but rather stall, is a malfunction of the carburetor. Let’s say the Stihl 180 saw worked properly, and then it was put on for a long time and did not use it. After it was started, and at idle, it works well, and when you press the gas, it can stall. Why stalls? The reason is a sticky carburetor injector valve. Of course, this is not 100%, but the probability of such a malfunction is high. We recommend reading an article about the device and repair of the Stihl 180 carburetor.

In order to check the injector, it is necessary to remove the carburetor and disassemble it. To remove, it is necessary to unscrew the two nuts securing the air filter and the carburetor, then remove the air filter and the engine control lever, while disconnecting the choke control rod from the carburetor. Next, you need to slightly pull the carburetor towards you, and disconnect the fuel supply hose.

It is necessary to remove the fuel hose as carefully as possible, and prepare a plug for it in advance, since fuel should come from it.

Having removed the carburetor, it must be blown out and cleaned of dirt, only after that the carburetor can be unscrewed.

It is necessary to unscrew the cover of the main chamber of the carburetor, 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. Knock out the valve.

It is necessary to knock out the valve by installing the carburetor on a wooden stand, this will ensure its protection from damage to the body.

After the nozzle is removed, you can blow it out with a compressor. The valve should only let air through in one direction, if the valve can be freely blown in both directions, then it is defective and must be replaced with a new one. Collect the chainsaw after the valve is repaired, it is necessary to follow the reverse sequence of disassembly.

You can clearly see how the carburetor is being repaired, or rather, how to properly knock out the nozzle valve from the carburetor body by watching the video.

Another common reason a saw can stall when revving up is air leaks into the carburetor. It is possible to check this only with a special tool, but it is worth noting that if preventive work on the carburetor has not been carried out for a long time, then a new set of gaskets can be installed in the carburetor. In some cases, this helps to solve the problem with its depressurization.

When disassembling the carburetor to replace the gaskets, you need to carefully inspect its needle valve, press the rocker arm and check its lifting. Sometimes, especially after the Stihl chainsaw has stood for a long time with fuel in the carburetor, the needle may burn to the carburetor body and not perform its functions. Simply put, the needle valve will not allow the fuel mixture to pass through. In this case, the saw will not work.

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Why stalls at full speed

Very often you can hear the question why the chainsaw stalls at full speed. There may be several reasons. First, you need to consider how the saw stalled. Suppose the tool worked fine and suddenly, for no apparent reason, it suddenly stalled and the starter did not turn. In such a situation, you can be 100% sure that the chainsaw is jammed and you need to start its overhaul.

The second situation is when the Stihl 180 chainsaw worked normally, then gradually lost power in a short time and stalled, while the cylinder overheated. In this case, most likely the reason is air leaks under the rubber pipe connecting the carburetor to the cylinder or its rupture. The mixture was depleted, resulting in overheating. You can eliminate the cause by changing the pipe.

Air filter dirty

It is quite easy to make sure that the air filter is dirty. You just need to remove it and start the chainsaw without it. if the saw works fine, then it’s in it and it just needs to be changed or washed, depending on its type. And do not be afraid that the chainsaw will work for a while without dust protection. if there is no dust cloud around you, then everything is fine.

So, remove the air filter. To do this, you need to remove the cover from the rear upper part of the chainsaw, which is fastened either with screws, or simply with some kind of lock that you just need to turn or snap off.

If the saw operates normally when the filter is removed after starting up, then it is dirty.

The air filter is either felt or nylon. The first resembles cotton wool or synthetic winterizer, and the second looks like a fine mesh of nylon threads stretched over a plastic case. Felt needs to be changed to a new one, but nylon can be simply washed in soapy water, dried and put back in place.

Nylon filter

Felt filter

Well, then we calmly use the chainsaw.

Let’s analyze these cases separately.

A Mower That Quits When Hot

Cleaning and adjusting the carburetor

If all of the above did not help, then, most likely, adjustment or cleaning of the carburetor is required. It is not recommended to do these procedures on your own, since most often such attempts still end with a trip to the service. So it’s better to go there right away and not disassemble anything on your own. But if you still want to dig deeper yourself, then it is best to watch a video that shows how experts do it:

I will end on this. Thanks for attention! Read more articles on this site! Until next time!

Any tool can break and the Stihl MS 180 chainsaw is no exception. Today we will try to understand such issues as: why the chainsaw stalls when the speed increases, also at idle and at full speed. Consider the options for diagnosing and eliminating malfunctions associated with this behavior of the Stihl 180 chainsaw.