No spark on gasoline trimmer

Why the grass trimmer gasoline does not start? Causes and remedy

Agree that almost any problem with the trimmer can be solved independently, without resorting to the help of specialists. When the lawnmower does not start, the causes and remedies lie on the very surface. You only need to conduct a thorough diagnosis of the device and identify the key causes of failure.

In this article, let’s consider popular causes of breakdowns of gasoline engines, ways to detect them. Here are recommendations for repair at home. To simplify the understanding of the process by beginners in this case, we will provide the material with illustrative photos and detailed video instructions.

Checking the fuel mixture

Suppose you do not start your grass trimmer. In this case, the first thing to do is to check if there is enough fuel in the tank and assess the quality of the fuel mixture. Only high-quality gasoline should be used to fill the motorized unit. It is recommended to use fuel, which brand is not lower than Ai-95. Filling the grass trimmer with fuel of unknown origin, bought not at the filling station, is fraught with the occurrence of frequent malfunctions of the tool. This can cause damage to the cylinder and piston system. Repair in such a case often exceeds the cost of the device itself.

Why the grass trimmer gasoline does not start? Incorrect preparation of fuel mixture, which consists of oil and gasoline, can also lead to it. The proportions in which these components are combined, are specified by the manufacturers in the manual of the grass trimmer. Preparing the fuel mixture is extremely not recommended in large quantities, that is, for the future. After all, if you save it for a long time, there is a loss of the defining properties of the substance. Therefore, if the grass trimmer does not start, it is worth to drain the old fuel and use a freshly prepared fuel mixture.

Troubleshooting the reasons why the lawn mower won’t start

The fuel mixture must be prepared with the exact proportions of gasoline and oil. You cannot use another brand of fuel. To prevent dirt from getting into the tank, leave the gasoline in a glass or metal container for 2 days. Do not use plastic containers for storing fuel. Oil precisely measured with a medical syringe without a needle. Use only freshly mixed fuel and do not leave unused fuel in the tank. If the engine is capricious, the lawnmower stops when you press the gas, the fuel may be to blame.

Lack of spark on the lawnmower repair with your own hands.

Why won’t the lawnmower start?? Troubleshooting for the grass trimmer

In this video we’ll try to look at the main malfunctions that occur during the operation of the moto.

lawnmower does not start when hot. pull the throttle trigger and yank the cord sharply several times until the engine starts, then put the trigger down. The lawn mower does not start the lawn mower does not start the lawn mower causes if there is no spark when cranking. Mower won’t start. requires specialized repair.

Check the ignition system, if the lawnmower does not start, is carried out sequentially:

  • clean the removed spark plug from soot and dirt, dry it, set the gap of 1 mm;
  • connect to the high-voltage wire and check for spark by yanking the starter several times;
  • if there is no spark, check for continuity of the high-voltage wire;
  • Replace the spark plug;
  • dry the spark plug passage;
  • at the same time check the work of the ignition coil, it is faulty if the working spark plug does not spark.

It is in the case of a faulty ignition coil, the lawnmower does not start when hot, it stops, works intermittently.

Cleaning or replacing the air and fuel filter will ensure the proper flow of ingredients into the carburetor. The air filter can be washed in soapy water or replaced. If nylon cloth is used, wash it, replace the porous felt filler. The fuel filter is changed carefully without leaving the intake pipe open. Do I Need to Change the Air Filter? you can tell if the engine starts with the air cleaner removed. If your lawnmower won’t start, you can change the grid if the mower won’t start by drying the spark plug.

The breather plug, the air inlet in the gas tank. Entrance and entry to if a gasoline grass trimmer does not start well or a lawn mower is better. If it is clogged, it creates a vacuum in the tank and the mixture does not flow into the carburetor. The hole can be blown with air or cleaned with a needle. Clean the exhaust duct, remove the muffler’s anti-sparking mesh.

Why the lawn trimmer does not start? Grass trimmer malfunction diagnostics

In this video we will try to review the main malfunctions that occur during the operation of the moto.

Mower won’t start when hot. squeeze the throttle trigger and yank the cord sharply several times until the engine starts, then put the trigger down. Lawn mower won’t start Mower won’t start if no spark occurs during cranking. Does not start. need specialised repair.

Check the ignition system, if the lawnmower does not start, in sequence:

  • clean the removed spark plug from soot and dirt, dry it, set the gap of 1 mm;
  • connect it to the high-voltage wire and check the spark by yanking the starter a few times;
  • If there is no spark, check the high-voltage wire for continuity;
  • replace the spark plug;
  • Dry the spark plug passage;
  • at the same time check the ignition coil, it is faulty, if the working plug does not spark.

It is in the case of a faulty ignition coil that the lawnmower does not start on hot, stops, runs intermittently.

Cleaning or replacing the air and fuel filter will ensure the proper flow of ingredients into the carburetor. Air filter can be washed in soapy water or replaced. If a nylon blade is used, it is washed, the porous felt filler is replaced. Replace the fuel filter carefully, without leaving the intake pipe open. Does the air filter need to be changed? can be determined when the engine is running with the air cleaner removed. Do you need to change the grid on the fuel supply if the lawnmower won’t start, a dry spark plug will tell you.

The breather plug, the air inlet in the gas tank. Inlet and inlet on if the gasoline grass trimmer doesn’t start well or the lawnmower is better. If it gets clogged, there is a vacuum in the tank and the mixture does not flow to the carburettor. The hole can be blown with air or cleaned with a needle. Clean the exhaust duct, remove the muffler’s anti-sparking grid.

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Adjusting and tuning the carburetor

Maximal and minimal engine revolutions, even idle speed are regulated with a carburetor. On the amount of fuel mixture and air fed, their ratio depends on the stable operation of the lawnmower. The lawnmower does not start if the carburetor is out of adjustment. The adjustment procedure for low (L), high (H) and idle (T) revolutions is regulated with the same-name screws:

spark, gasoline, trimmer
  • The chainsaw has to run for at least 10 minutes, because the adjustment is done while it is hot.
  • Screw H is turned smoothly to the maximum revolutions, then turn ¼, counterclockwise, reducing the speed of the engine shaft.
  • Idle speed should be adjusted with the T-screw until the grasshopper doesn’t rotate.
  • Screw L is adjusted by first opening the throttle as much as possible, and then gently reducing the revolutions to a steady minimum.

After adjustment, an operating carburetor with cleaned filters and checked ignition should ensure engine operation. Gasoline grass trimmer. surprisingly useful thing, grass trimmer does not start after. If the carburetor is faulty, after repairing it, the feed system will need to be adjusted again before starting the lawnmower.

Rare breakdowns that prevent the lawnmower from working can be:

The most important fault, the removal of which is associated with the replacement of the engine can be a failure of the engine piston group. The cost of repair will cost about 70% of the cost of the product. To understand the reasons why the lawnmower does not start. will help

Lawnmower won’t start? The most common cause can be eliminated

Chinese brushcutter headache for the owner, but still without them nowhere. The main problem is the difficulty to start after long idle time. If the lawnmower worked like clockwork in the fall, and does not start in the spring, then most likely you need to disassemble the carburetor and clean its valve.

Necessary tools:

If the brushcutter engine refuses to start, then the first thing to check is the spark plug. If it’s completely dry, it means there’s no fuel in the combustion chamber and the reason is the carburetor. Immediately it is worth checking the spark plug and for the spark to exclude it from the causes on all fronts.

You can also check if the motor itself is in good working order. To do this, unscrew the plug, you need to pour a syringe into the combustion chamber a few milliliters of gasoline. The spark plug is then screwed in and the lawnmower starts. If there is nothing wrong with the motor, it will run for a few seconds. This confirms once again that it makes sense to disassemble the carburetor.

Then the plastic protective cap is removed along with the air filter. After that, a Phillips screwdriver unscrew the 2 screws that hold the air damper and carburetor on the engine. Immediately the fuel pipes are torn off.

At the side of the choke cap you need to unscrew 4 screws with a screwdriver and divide it into two halves. We are interested in the half with the choke. On the inside, in the center, there’s a valve.

It often gets stuck, because after the evaporation of gasoline at idle, it leaves a viscous oil that works like glue. To check it, you need to put a short thin tube and try to blow air through it. If it is stuck, it can not be blown in any direction.

A stuck valve can be cleared with a match. Toothpicks are not a good idea because they are sharp and can cause damage. You have to put a match in the valve and loosen it. After you clean it with a match, it will blow out.

The fuel will be able to flow, so it should start working. Cleaning the valve is not the panacea for all brushcutters that don’t start after idle time, but it helps in 8 out of 10 cases. The other 20% is usually carburetor related too, usually the needle.

And again the carburetor.

If your weed trimmer won’t start even after all this mockery, you can’t do without disassembling the carburetor. It is very possible that a stuck needle in it is to blame. In any case, disassembly and flushing of the capricious mechanism certainly would not interfere. Adjusting the lawn mower carburetor can be done with your own hands lawn mower, like all gasoline garden tools, is not a difficult technique to maintain. Repair, adjust without the help of others is possible and necessary. For example, adjustment of the lawnmower carburetor with their own hands. a matter of 5 minutes. The carburetor from the lawnmower. is a node in the power system. Idle.

Many owners of trimmers face a problem when the device simply does not start.

One of the circumstances may be the lack of spark. Usually this happens when the fuel floods the spark plug. In addition, you need to check the plugs for serviceability, as this can also lead to a lack of spark.

The first sign of a faulty spark plug is the presence of a short circuit between its contacts, and in short. No spark on the trimmer.

In addition, the spark plug is considered faulty in the event that it is covered with a black wet layer.

Such a layer appears from oil in the combustion chamber. In such a situation, you have two choices: either clean the spark plug properly, or buy a new.

Sometimes it happens that the plugs are clean, but, at the same time, the problem may be in its insulation, which is often covered with black dry carbon deposits.

The cause could be a weak spark plug, a spark plug temperature that is too low, poor fuel quality, a dirty air filter or prolonged idling.

Here the solution is the same: either clean the spark plug or replace it with a new one. over, the spark plug should also be replaced if the contacts are badly worn.

Lack of spark on chain saw

Missed spark on chain saw. repair with your own hands.

Parts for Chinese brushcutter The Chinese lawnmower does not start.

In the case where there is no spark on the trimmer, how to solve the problem you will prompt the professionals at the service station.

Sometimes the problem may be with the magneto. Magneto can fail because you could pull the starter cord at the moment when the ignition was off, and the plug was not grounded to the mass.

Such actions can easily damage the magneto. In such a situation, the only solution is to buy a new magneto.

In addition, the problem may lie in the ignition assembly. This option can be considered if the spark plug and wire do not have any faults.

In such a situation, it is necessary to deal with the replacement of the ignition unit. It can be found attached to the engine cylinder with two screws.

To gain free access to the assembly it is necessary to remove the guard.

To correct the situation you will need to replace the whole assembly, since practice has shown that replacing individual parts is not enough.

If there is no spark at the trimmer, there is only one way to fix it: replace it.

over, sometimes the problem should be looked for in the ignition coil. The lack of spark can be caused by coil failure or malfunction in the circuit.

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To check the current flow in the coil primary winding, you can use a light bulb that should be turned on instead of the coil.

Gasoline trimmers use both two-stroke internal combustion engines (ICE) and four-stroke. But the ignition system in them does not differ from each other, so the repair and adjustment of this fuel ignition system will be the same for different types of ICE.

Ignition system of two-stroke ICE consists of 2 elements: flywheel and coil (magneto). The illustration below shows what they look like.

On the flywheel there is an impeller, which works as a fan to cool the engine. Also on one side of the flywheel are permanent magnets, shown with an arrow in the figure.

As the flywheel rotates, an electric current is produced in the coil, which serves to produce a spark on the spark plug. The spark appears at the moment when the magnets are directly under the magneto.

Missing spark on a chainsaw

Missing spark on a chainsaw repair with your own hands.

Spare parts for Chinese brushcutter does not start the Chinese lawn mower.

If there is no spark on your petrol trimmer, the professionals at the service station will tell you how to solve the problem.

Sometimes, the problem may be with the magneto. The magneto may be destroyed because you may have pulled the starter cord when the ignition was off and the spark plug was not grounded to earth.

Such actions can easily damage the magneto. In this situation, the only solution is to buy a new magneto.

In addition, the problem may lie in the ignition assembly. This option can be considered if the spark plug and wire do not have any faults.

In such a situation, it is necessary to deal with the replacement of the ignition assembly. It can be found attached with two screws to the engine cylinder.

To gain free access to the assembly it is necessary to remove the outer casing.

To correct the situation, the whole assembly will have to be replaced, since practice has shown that replacing individual parts is not enough.

If there is no spark at the trimmer, there is only one way to fix it: replace it.

over, sometimes the problem should be looked for in the ignition coil. No spark can be caused by coil failure or malfunctions in the circuit.

To check the current flow into the coil’s primary winding, you can use a light bulb to turn it on instead of the coil.

Gasoline trimmers use both two-stroke internal combustion engines (ICE) and four-stroke. But the ignition system in them does not differ from each other, so the repair and adjustment of this fuel ignition system will be the same for different types of ICE.

The ignition system of a two-stroke combustion engine consists of 2 elements: the flywheel and the coil (magneto). The illustration below shows what they look like.

On the flywheel there is an impeller, which works as a fan to cool the engine. Also on one side of the flywheel are permanent magnets, shown with an arrow.

spark, gasoline, trimmer

As the flywheel rotates, an electric current is produced in the coil, which serves to produce a spark on the spark plug. The spark appears when the magnets are directly under the magneto.

Why the ignition adjustment is needed

In some cases, when the engine does not start, it will be necessary to adjust the ignition. Of course, it is first necessary to check the serviceability of the spark plug and the high-voltage cable with the cap.

Ignition adjustment on a two-stroke engine is needed to ensure that the fuel is ignited in time in the engine combustion chamber. Below is a diagram, from which you can understand the principle of the internal combustion engine.

The spark should appear when the piston compresses the fuel and does not quite make it to top dead center. When the piston passes TDC, the fuel mixture is ignited and the piston moves downwards as a result of the explosive energy.

Therefore, if for any reason (mainly due to displacement of the flywheel on the shaft relative to its original position) ignition occurs before the piston passes TDC, it goes back and the crankshaft is cranked in the opposite direction. Such movement can damage the starter unit, break the starter cord, etc.д. If this is the case, there is early ignition of the fuel.

It can also be late ignition on the trimmer: the piston, after compression of fuel that has not ignited, goes down, and at that moment there is a spark. In this case, the engine either will not start or will significantly lose power and will not pick up speed well.

But such problems with early or late ignition on two-stroke engines are quite rare, because the flywheel with magnets is already set in the right position, which is perfectly synchronized with the movement of the piston. In addition, the flywheel is fixed to the shaft with a key and a nut. It is therefore not possible to mount the parts in the wrong position.

Basically, the adjustment of the ignition is to align the correct gap between the magneto and the flywheel.

spark, gasoline, trimmer

The lawnmower does not start well? Adjust the magneto gap

As experience shows in the use of chain saws, particularly Chinese-made, they often have problems with the starting system, so it’s often difficult to start them. The problems are usually related to the flywheel of the magneto.

For those unfamiliar with this unit, a reminder: this system, which consists of the ignition coil, spark plug and flywheel with magnets. We have to deal with the magneto gap, or to be more precise, the ignition coil gap and how to set it reliably. It is because of this that problems arise in Chinese units, which have been operated for several years in domestic conditions or in the conditions of the utilities department. But it happens that even in new products it is difficult to start, especially in the cold. And in this case, the starting problems are usually related to the magneto gap. Most people who operate lawn mowers, set the gap magneto 0.4 mm, as recommended by many manufacturers. What happens if this gap is corrected and 0.25 mm is set? It turns out that by reducing it, the electric spark becomes thinner, shallower and works out every stroke even at slow revolutions of the magneto flywheel.

That is, by consciously reducing the gap, we thereby increase the likelihood of a normal start of the lawnmower without any excessive physical exertion and shortness of breath, even when starting a cold engine.

The clearance and how to set it in different cases

As a template for adjusting the clearance of the magnetos, you can successfully use a strip of the desired width and length, cut from an ordinary plastic bottle, for example, from a Pepsi-Cola bottle.

Only it should be installed last, so as not to damage it during repair work, using the same hair dryer for any purpose. After all, if it is warped by hot air, you can’t talk about accurate alignment of the magneto gap. It is with the help of a spacer cut from a plastic bottle that the magneto gap can be accurately set to 0.25 mm, because its thickness is precisely. To be sure of this, simply fold the strip in quarters and measure its total thickness with a caliper, which will be exactly 1.0 mm. We put the spacer, cut out of a plastic bottle, on magnetite’s flywheel magnets, put the ignition coil on its place and fix it by solid bolts 8 by 8, previously filling the holes with a thread on the body with a thread locker.

It is also applied to the bolts, screwing which you must not forget to secure the ground terminal. It’s better to use an electric screwdriver. Push the bolts to the limit by hand with an ordinary hand screwdriver with a hex bit, since the use of an L-shaped hexagon can tear the faces of the heads of the bolts.

It remains, having turned the handwheel with magnets, to remove a plastic spacer and, continuing to turn it, to check quality (uniformity) of a gap at its turn from 0 to 360 degrees, which at such approach turns out ideal. Some people use a double folded xerox sheet to adjust the magneto gap, which is also acceptable, but the use of a spacer made of a plastic bottle gives a better result. All the more so that it can be reused dozens of times.

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It remains only to install the body parts and you can start the engine to test how it starts and runs. Sometimes in the process of exploitation the nodes of fixing the ignition coil to the magneto body are deformed, which does not allow its safe installation, as the holes in the coil and in the engine body do not coincide.Of course, one may try to straighten the defect, but it is safer to buy a new coil, as it is not too expensive.All further actions are similar to the above described case, except that the heads of the ignition coil bolts may not be hexagonal, but wrench and Phillips screwdriver. But this does not change the point: the tightening of these bolts must be guaranteed, as in the first case. To assess the quality of the work done, you need to make sure the presence of the spark between the electrodes of the plug visually after the final assembly of the engine. To do this, we connect it to the mass and start turning the engine with a manual or electric starter. Checking for the spark has one nuance. If you pull sharply on the kickstarter, the spark will appear even with a little faulty magnetos magneto and even a completely inoperative ignition coil. In this case, the presence of a spark is not an indicator of the ignition system malfunction.On the quality of the spark formation can be judged only when it appears when the flywheel magneto is not rotated too quickly, for which the kickstarter should not pull, and evenly and slowly pull.

Only in this case, the engine of a gasoline trimmer or chainsaw will start without problems, both for the first time in the morning, and throughout the working day (respectively, the so-called hot or cold start). If there is no spark when the starter is moving slowly, you will most likely have to change the ignition coil, set the magneto gap or change the spark plug.The above-described practice of setting the clearance on chain saws has paid off over the last five years. There have never been any complaints from users after such a repair. It really helps to start not only Chinese but also European and even branded chainsaws. On all machines, regardless of manufacturer, setting the clearance at 0.25 mm instead of the 0.40 mm recommended by the factories, provides excellent results. Some people suggest a play of 0.10-0.15 mm, but this is too small. After all, there is a certain thermal expansion of the ignition system parts, the body itself, the crankcase of the lawnmower or chainsaw, and such a small gap can disappear at all, which can lead to a breakdown (burnout), primarily of the ignition coils. That’s why the 0.25 mm gap is optimal from every viewpoint.

complex causes of mower failure

If the step by step troubleshooting procedure did not work and your grasshopper still fails to start or stops, it is worth inspecting the carburetor and the engine itself. A clogged carburetor can be one of the causes, unstable operation of the tool. There are three main problems here:

  • Clogged ducts or jets. Clean it all with special washes or with a powerful jet of compressed air from a compressor. Do not use needles and wire, as the passages can be damaged;
  • Worn out carburettor gasket. The solution is to replace the failed gasket;
  • Leaky gasket. 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 fall, it means that some part of the carburetor is defective. You will have to find it and replace it with a new one.

If everything is okay with the carburetor, the gasoline grass trimmer may not start due to wear and tear of the piston group. If you find chips, scratches or scrapes on the piston or cylinder, they should be replaced. Piston rings must be checked. A small backlash of the piston when rocking the connecting rod indicates that it is time to change the rings. This procedure is best left to professionals at a service center.

How to use and store your lawnmower

To ensure that the lawnmower starts well in the future, it is necessary to ensure good storage and operating conditions:

  • Monitor the cooling system closely during operation and clean the housing channels and starter ribs thoroughly and promptly;
  • If necessary, use solvents, kerosene or other cleaning agents for cleaning;
  • do not clean the tool “hot”. let it cool down;
  • strictly follow the operating instructions or you could overheat the engine;
  • If you do not plan to use the mower in the next month, drain the fuel mixture from the mower, t. к. Over time it will break up into heavy fractions that will definitely clog the carburetor passages;
  • after draining the fuel, let the trimmer run at idle speed until it stops, this will help remove the remaining fuel mixture completely.

Before winter storage, do the following steps

  • completely disassemble the braid, rinse and clean all the parts you can;
  • Inspect the parts for damage, and if necessary, repair misalignments, rips, bends, and any other malfunctions;
  • Fill the gearbox with sufficient oil and clean the air filter;
  • You may partially disassemble the engine and flush, purge, and lubricate all moving parts;
  • In order to lubricate the piston, it is necessary to unscrew the spark plug, raise the piston to the extreme dead point with the starter, pour some oil into the spark plug hole and twist the crankshaft a couple of times;
  • If you don’t store your mower indoors, wrap the engine in an oily rag.

Remember, careful adherence to the rules will allow you to forget about bad lawn mower starts for several seasons.