Stihl Trimmer Won’T Start

For what reasons the Stihl MS 180 chainsaw will not start
Why the Stihl 180 chainsaw does not start. Major malfunctions and causes. Ways to eliminate and repair the Stihl MS 180 chainsaw.

Floods the candle

In the people, the phenomenon in which a spark cannot ignite a large amount of fuel is usually called candle flooding. The cause of the malfunction lies in the carburetor, or in improper cold start. If a malfunction is detected, first you need to “purge” the engine.

Problems with the ignition coil. Algorithm for checking for lack of fuel supply

Unscrew the candle;
Using a syringe, pour 1-2 cubes of the fuel mixture into the spark plug hole;
Install the candle and put on the cap of the high-voltage wire;
Set the engine control lever to the hot start position;
Pull the starter several times.

If, after several movements with the starter, the Stihl 180 chainsaw started up and immediately stalled, then the suspicions in the lack of fuel supply were confirmed and you can proceed to further diagnostics of the fuel line.

Checking the pulse from the engine crankcase

The fuel pump on the Stihl MS 180 chainsaw is installed directly in the carburetor and operates under the influence of pulses from the engine crankcase of the Stihl 180 chainsaw.

Clogging of the channel is fraught with the appearance of problems with the supply of fuel or its complete absence. To check the branch pipe, it is necessary to remove the air filter housing and the carburetor, and then check the channel for clogging with a thin metal wire.

Another reason associated with the absence of an impulse in the pipe channel is the depressurization of the engine crankcase, which results in air leakage from it and a decrease or complete cessation of its supply to the fuel pump. Depressurization results in partial or complete loss of the fuel pump’s performance. To check the tightness of the crankshaft oil seals, and indeed the crankcase of the Stihl 180 chainsaw, a special vacuum meter is used, and since it is a special-purpose tool, it is mainly available only in service centers. The question arises, what to do?

You can check the pulse supply using a syringe on the engine with the carburetor removed. You will need to draw a little oil into the syringe to lubricate the engine and squeeze it out into the impulse channel of the pipe, and then pull the starter. If the impulse does not pass, the oil will remain in the channel and you should look for the cause deeper, disassemble the engine and check the oil seals. If the oil is squeezed out of the channel, then the problem may be hidden in the fuel pump itself.

Fuel line diagnostics

Typically, the diagnosis of the fuel supply system begins with checking the condition of the fuel filter. To do this, unscrew the tank cap and, using an aluminum wire bent at the end, remove the fuel hose from the tank with a filter at the end.

Having taken out and dismantled the filter, you can try to blow into it, if air does not flow, then the problem has been found. If everything is in order, then you need to check the system for clogging.

To check the fuel supply hose, it is necessary to disconnect it in the place where it connects to the carburetor, and then blow into it. The clogged hose can be mechanically cleaned; if this is not possible, replace with a new one.

In the event that the supply hose and the fuel filter are normal, and the fuel supply is not observed, the cause may be hidden in a malfunction of the air pulse to the fuel pump.

Engine “purge” algorithm

Important: under no circumstances should you “purge” the engine with the ignition on and near an open flame.

Unscrew the candle;
Turn the Stihl 180 chainsaw upside down and drain off excess fuel;
In the inverted state, pull the chainsaw starter several times (thus, under the influence of compression, excess fuel will be removed from the cylinder);
Install the plug and the cap of the high-voltage wire in place;
Set the engine control lever to the hot start position;
Pull the starter motor several times and start the engine.

If everything is in order with the Stihl chainsaw and the cold start algorithm was simply violated, then after the “purge” it should start. Otherwise, the fault must be sought in the carburetor.

What could have broken

Problems with the petrol brush, due to the fact that this device does not start, are classified in a certain way by service specialists. They highlight faults with the following components of the mechanism:

An engine in which the piston and bearings may wear out or fail, crack the crankcase;
The fuel supply system, while the filter may be clogged or problems with the carburetor;
Mechanical damage to wires, tubes, hoses;
Ignition circuit.

Why does the petrol trimmer stall

A scythe with a gasoline drive is a useful thing for owners of home gardens, lawns, and when the trimmer suddenly stalls, the work on clearing the area from grass stops. The device itself is a rather complex mechanism, so there are many different reasons for its breakdown. The most common problems are contained in the operating instructions. You should know the reasons why the trimmer stalls in order to effectively repair the device yourself.

Immediately after wound up

The unit may stall immediately after starting if the carburetor is misaligned or incorrectly adjusted. This causes an uneven fuel supply. The result of this is that the device vibrates distinctly. For troubleshooting, the carburetor is reconfigured, following the instructions for the mechanism.

Also, the engine stops when the fuel supply valve becomes clogged. In such cases, it is sufficient to simply clean it. If the brushcutter first worked, but then immediately stalled, then perhaps the fuel enters the carburetor unit with some difficulty. Weakening the valve helps to resolve the issue, which ensures free circulation of the mixture in the system.

The stoppage can also be caused by air leakage in the presence of mechanical damage to the hose (holes, cracks) that takes the fuel. In this case, add more revolutions to the drive in order to quickly expel air bubbles from the system.

When heated

The brushcutter often stops when it heats up. At the same time, it starts up, works “jerky” and gradually stops. This process occurs when the gasoline in the carburetor boils or the damper is installed in a rotary rather than disc type. In the latter case, the part is changed.

It happens that the trimmer heats up if the ignition circuit wire or coil is damaged. In order for the device to start working normally, parts are replaced.

When you press the gas

If, when you press the gas, the petrol cutter stops, then the reasons may be as follows.

The most common scenario is carburetor adjustment failure, which occurs when the drive is under significant stress, after prolonged inactivity of the mechanism, or when it is used in difficult conditions.
Clogging of the fuel valve, which is eliminated by loosening it, as a result of which gasoline begins to flow normally through the system.
Loosening and drooping of the cable in the carburetor. The fuel hose can also be stretched to the point of rupture due to significant stress.
Clogged breather (non-return valve), as a result of which fuel does not flow into the tank.

If the problem is related to the carburetor unit, then it can be recognized by the appearance of vibrations of the brushcutter. When the hose bursts or the cable stretches, these components are replaced.

Idle

At idle, common reasons for stopping the trimmer are as follows:

Dirt, misalignment or incorrectly adjusted carburetor adjustment;
Clogged air filter;

Replacing the air filter of brushcutters

Trimmer air filter

Reducing the speed of the gearbox when it heats up, which is a consequence of the use of an unsuitable fuel mixture;
Clogged throttle;

Air ingress into the system;
Not enough fuel to operate the petrol cutter.

Checking the fuel mixture

Before starting the engine of the gasoline streamer, check the presence and quality of the fuel mixture. Do not save, do not be greedy and do not be clever in this matter. Repair or replacement of the piston group will cost you too much (sometimes up to 70% of the cost of a new tool). Prepare the oil-fuel mixture strictly according to the instructions. Calculate its amount based on real needs. Excess gasoline left over after work loses its quality over time.

Why the petrol cutter won’t start. Troubleshooting

Caring for the personal plot, summer residents periodically encounter the fact that the petrol cutter does not start. There are many reasons for tool failure. For the correct diagnosis of the problem, the owner of a useful unit in the country needs to know the device and the principle of operation of its individual parts.

How to start diagnostics of brushcutters
Checking the fuel mixture
We carry out diagnostics of a candle and a candle channel
Diagnostics of filters for petrol cutters
Breather and exhaust port
Complex reasons for the failure of petrol cutters
Rules for the operation and storage of petrol cutters

We carry out diagnostics of a candle and a candle channel

If the quality of the fuel mixture is not in doubt, and the brushcutter stalls when starting, then a flooded candle may be the cause. Here, for repairs, an ordinary candle wrench is suitable (every motorist probably has) and a spare candle.

We unscrew the candle and wipe it;
Dry it thoroughly (do not ignite);
We drain the excess fuel in the chamber through the spark plug hole and dry it;
We clean the old candle from carbon deposits using a file or a lady’s file;
We expose a gap with a distance of 1 mm (you can check with any coin);
We put everything back in place and try to start the trimmer.

If the candle is working, the socket where it is located is completely dry, and the petrol cutter does not want to start, lubricate the threaded connection with gasoline. It should be slightly damp. No matter how wonderful a spark the candle may give out, there is simply nothing to ignite in a dry chamber.

If the trimmer motor still does not start, you should exclude such a reason as the absence of a spark due to poor contact between the spark plugs and the high-voltage wire. If the connection is of good quality, but there is still no spark, most likely, your ignition unit has “flown”. Here it will not be possible to do without a master, since the part is not repaired, but sold as a single unit.

Breather and exhaust port

Often, “gentle” branded models of petrol cutters do not start and stall due to the contamination of the breather. The main function of this element is to equalize the pressure in the gas tank. When this unit becomes clogged, a vacuum is created in the tank, preventing the supply of fuel. You can eliminate the malfunction by cleaning the breather. You can use a regular needle for cleaning.

Normal operation of streamers with internal combustion engines can be disrupted due to dirt entering the exhaust channel or a clogged silencer mesh. There is such a problem on older generation models. The issue can be resolved by traditional cleaning and removal of the anti-spark grid.

How to start diagnostics of brushcutters

If the brushcutter does not start or immediately stalls after starting, it is necessary to sequentially check all the main components and assemblies. The verification algorithm is as follows:

Fuel tank (fuel quality);
Candle and candle channel;
Air filter;
Fuel filter;
Breather;
Outlet channel.

These nodes are most often the source of major problems that can be eliminated after a thorough inspection.

Complex reasons for the failure of petrol cutters

If the step-by-step troubleshooting algorithm does not work, and your scythe still does not start or stalls, it is worth inspecting the carburetor and the engine itself. A clogged carburetor can be one of the reasons for erratic tool performance. There are three main problems here:

Clogged ducts or nozzles. All this is cleaned by special washes or blown by a powerful jet of compressed air from the compressor. Do not use needles and wires, as the bore may be damaged;
Worn carburetor gasket. Exit. Replacement of a failed gasket;
Violation of tightness. To check this indicator, you can use an ordinary household tonometer, replacing it with a suitable pressure gauge. Watch the readings: if they do not change, everything is fine, and if the pressure starts to drop, then some part of the carburetor is faulty. We’ll have to find it and replace it with a new one.

If everything is in order with the carburetor, then the petrol trimmer may not start due to wear of the piston group. If chips, scratches or scuffs are found, the piston or cylinder should be replaced. Piston rings are subject to mandatory checks. A small backlash of the piston when rocking the connecting rod indicates that it is time to change the rings. It is best to entrust this procedure to the specialists of the service center.

Perform cold starts correctly!

Often gasoline trimmers do not start after trying to “put them into operation” after long-term storage. Launch failures in this case are often caused by incorrect user actions.

If you are faced with this very phenomenon, then during a cold start you need to close the damper, and then pump a small amount of the fuel mixture into the carburetor. Then pull the starter handle until you feel resistance, then start the trimmer with sharp and energetic movements.

The main thing. Fuel mixture!

In this case, the remnants of plastic dissolved in an aggressive environment do such terrible things in the combustion chamber that you will definitely not be able to do without completely sorting out the mechanism. But you will certainly remember forever how to properly store fuel.

What to do when the fuel was definitely normal, there is a spark, but the petrol trimmer will not start? It is possible that you just filled the candle with gasoline. In this case, it must be turned out, wiped with a clean cloth and dried. By the way, it will be quite useful to check the candle itself for performance.

What to do when the petrol trimmers won’t start?

The petrol trimmer is a surprisingly useful tool, with which you can mow not only a miniature front lawn, but also a whole lawn of considerable size. Unfortunately, there is nothing eternal in this world, and therefore you may be faced with the fact that petrol trimmers do not start.

It often happens that users of this kind of cars are trying to “save money” by pouring into the tank not fuel with a normal octane number, but something incomprehensible that has been in a plastic canister for almost a dozen years.

Reasons

There are not only situations when petrol trimmers do not start, but there are cases when, after starting, they work for a couple of seconds and immediately stall. Inspect the spark plug again: if it is “thrown”, and this situation repeats even after wiping and drying it, go to the “revision” of the air filter.

Most likely, it is completely oiled and needs to be replaced. If everything is normal with the filter, it may be that the ignition coil is out of order.

In the case when the petrol trimmers do not start, and you have done all of the above, the muffler may be clogged. It must be dismantled, burned on a burner, after which all carbon deposits can be easily shaken out.

Even if your trimmer will not start even after such bullying, you cannot do without disassembling the carburetor. It may very well be that the falling needle in it is to blame for everything. In any case, disassembling and flushing this whimsical mechanism will certainly not interfere.

In general, when the trimmer began to be capricious and stall, it is advisable to carry out full prevention: completely change the fuel mixture, try a different oil, and also change the spark plug without fail. Practice shows that in many cases it is cheap poor-quality candles that are to blame.

We’ve covered the most common reasons why the trimmer won’t start. If the matter is in something more “exotic”, you cannot avoid going to the service center. You will probably find smaller and more obvious breakdowns yourself.

Perform cold starts correctly!

Often gasoline trimmers do not start after trying to “put them into operation” after long-term storage. Launch failures in this case are often caused by incorrect user actions.

The main thing. Fuel mixture!

What to do when the fuel was definitely normal, there is a spark, but the petrol trimmer will not start? It is possible that you just filled the candle with gasoline. In this case, it must be turned out, wiped with a clean cloth and dried. By the way, it will be quite useful to check the candle itself for performance.

What to do when the petrol trimmers won’t start?

Reasons

There are not only situations when petrol trimmers do not start, but there are cases when, after starting, they work for a couple of seconds and immediately stall. Inspect the spark plug again: if it is “thrown”, and this situation repeats even after wiping and drying it, go to the “revision” of the air filter.

Most likely, it is completely oiled and needs to be replaced. If everything is normal with the filter, it may be that the ignition coil is out of order.

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