Why lawn mowers do not start when hot

What to do if the petrol lawnmower won’t start

Despite a fairly wide range of lawn mowers with different principles of operation, gasoline mowers do not lose their popularity. They earned respect among users due to their power and autonomy.

For a comfortable process of work and the absence of breakages during the operation of the lawnmower, as well as other garden equipment of similar action: trimmers, brushcutters, very important is the first startup. If you do not pay enough attention to the preparation of the equipment for use, it can affect the quality of work or lead to damage to the unit.

Construction of a petrol lawnmower

Before you repair the device, you need to understand what it consists of. There are many models of garden equipment from different brands: self-propelled, non-self-propelled. They are all built the same way. Constituent parts of the design:

  • platform on wheels;
  • gasoline engine (starter, carburetor, ignition and fuel system, air damper, filter, piston system, fuel tank.);
  • hand crank;
  • water jet nozzle;
  • cutting elements (blades);
  • grass catcher (container);
  • throwing unit of freshly mowed grass;
  • buttons, control levers;
  • body (aluminium, steel, plastic).

The structure of the gasoline lawnmower

Before repairing the device, you need to understand what it consists of. There are many models of garden equipment from different brands: self-propelled, non-self-propelled. They are all built the same way. Constituent elements of construction:

  • platform on wheels;
  • gasoline engine (starter, carburettor, ignition and fuel system, air valve, filter, piston system, fuel tank.);
  • hand crank;
  • water jet nozzle;
  • cutting elements (blades);
  • grass catcher box (container);
  • Freshly cut grass ejection unit;
  • buttons, control levers;
  • housing (aluminum, steel, plastic).

Restoring the functionality of electrical equipment

Mowers, which have electric motors inside, most often begin to get cranky due to oxidation of the contacts. The terminals become encrusted with a layer of scale from excessive moisture in the room or other storage. It is also worth checking that there are no broken wires in the problem areas. Use a multimeter or other type of tester for this operation.

When a set of gardening equipment contains a brush motor, then we identify the serviceability of the moving unit. Brushes can wear out quickly, causing a loss of contact. Repair kits with them cost relatively little, and it is easy to find them in specialty stores where they sell spare parts for such equipment.

Malfunctions also occur in asynchronous motors. Failure of phase-shifting capacitors occurs in them. This situation is difficult to diagnose at home. It can be identified by indirect symptoms:

  • A humming sound is heard;
  • When starting, the housing jerks slightly;
  • There is a significant heating of the motor, even with a small load;
  • RPMs are dropping.

It is worth carrying out a diagnosis of the state of the on-off switch/button and the voltage supply to the electric motor. When the testing of the described nodes has been carried out, and violations in the functionality is not detected, then it is unlikely to fix the breakdown of the lawnmower with your own hands. Then you have to call for service.

Why the mower won’t start, the reasons

You can find out the cause of the malfunction by disassembling the device. This should be done carefully and cautiously, there are many small parts inside that are easy to break. There are 2 types of damage: mechanical, electrical. Consider the most popular Causes why the mower does not start and does not linger:

  • The carburetor is out of order;
  • Bolt connections are loose;
  • Engine failure;
  • Jamming of moving components of the mechanism (crankshaft, piston);
  • Blockage of cutting tool (cylinder) by a foreign object. Branches, sticks, hard grass, rocks, etc.Д.;
  • Oil and fuel supply system is broken;
  • Candle failed to work;
  • Tensioned, torn belt;
  • Little or too much clearance between parts inside the structure;
  • Defective switch of device;
  • Dirty fuel hose, air vents;
  • Air filter clogged with.

Gasoline lawn mowers without interference when used for long periods of time. device kiosks. Why the mower won’t stand and start hot? Overvoltage motor. It is better to postpone mowing, let the mower stand, after it has stopped, most likely the reason is to overheat the device.

The most common faults of lawnmowers

As for problems with engine failure or jamming, they are virtually non-existent in cart-type lawnmowers, which we discuss in the article. These faults are more likely to be inherent in manual petrol lawnmowers, and account for almost half the reasons why their users call the service center.

Lawn mower won’t start? Eliminate the most common cause

Chinese brushcutters are a headache for the owner, but there’s nowhere to go without them. The main problem is that it’s hard to start after long idle times. If your lawnmower runs like clockwork in the fall and won’t start in the spring, you most likely need to disassemble the carburetor and clean its valve.

Needed tools:

If the brushcutter engine refuses to start, then the first thing to check is the spark plug. If it is completely dry, it means that there is no fuel in the combustion chamber and the reason is the carburetor. It’s worth checking the spark plug right away to rule out the cause on all fronts.

You can also verify the serviceability of the motor itself. To do this, unscrewing the spark 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 start for a few seconds. This will once again confirm that it makes sense to disassemble the carburetor.

Next, the plastic protective cover 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 tubes come off.

On 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 suction. There is a valve on the inside center.

It often jams because after the gasoline evaporates, viscous oil that works like glue remains on it when idle. To check it, you need to put a short thin tube and try to blow air through it. If it is stuck, it will not be able to purge in either direction.

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The valve can be jammed with a match. Do not use a toothpick, because it is too sharp and can cause unnecessary damage. Use a match to press lightly against the valve and loosen it. After cleaning with a match it will be blown out.

Fuel will already be able to flow, so it will work. Cleaning the valve is not the panacea for all brushcutters that don’t start after idle time, but it helps in about 8 out of 10 cases. The remaining 20% are also usually carburetor related, usually with the needle.

The main problems with gasoline cars

Initial diagnosis is carried out from the stage of eliminating the most obvious breakdowns. When the engine does not start, it is worth checking the presence of fuel in the tank. If there are remnants of it from last season, it is worth replacing it. Low-quality gasoline after wintering can lose its characteristics, give an undesirable sediment or even split into fractions in density. In this form, it is not capable of starting the engine, but will only clog the system.

At the second stage we find out why the spark does not appear. Its loss will not allow the fuel to ignite. Remove the cap from the spark plug and unscrew it from its seat with a special key from the mower. Then we put the cap on the spark plug, bring it close to the threaded part or metal part of the engine, while the partner pulls the starter.

With such manipulation in the working node must appear a powerful blue spark. It can be seen even in daylight. It is important to test it near an unpainted metal part of the motor that can conduct current.

When there is no spark, you need to go to the store for a new spark plug. It is not worth returning to the engine even if the spark is weak or unstable. It is better to clean the working pins from carbon deposits on the spark plug head beforehand.

During the operation it is possible that the rattling in the structure. At first it does not affect the overall performance of the mechanism. However, it can cause imbalance and increased noise during operation. It is worth retightening the fixing bolts on the frame in a timely manner.

An uneven cut in the grass is an indication that the mower blade needs sharpening. Getting to them is not that difficult, but it is important to unplug the equipment completely. Work on your own with a vice and file or on a sharpening stone. It is important to ensure that the cutting angle is uniform throughout the line of 30 degrees. If there are gouges in the surface, this is a sign of hitting a hard surface. Replacing them will be quite expensive.

A whistling noise occurs when the mower is switched on. Unpleasant acoustic effect is associated with the penetration of foreign elements inside the structure. They can block the roller in the aerator. You can solve the problem by disconnecting the blocked roller and then removing the foreign object.

The motor of gasoline-powered equipment becomes almost as soon as you start working for a short time. culprits. a jammed crankshaft or piston. At the same time check the oil in the crankcase. on a disconnected engine manually start the rotation or refill the oil as needed. However, in such a situation, it is more often necessary to call for the restoration of the.

Rules of operation and storage of lawn mower

For the lawnmower to start well in the future, it is necessary to ensure good storage and operating conditions:

  • during work keep a close eye on the cooling system, clean the channels in the housing carefully and in time as well as the starter ribs;
  • If necessary, use solvents, kerosene and other detergents for cleaning;
  • Do not clean the tool “hot”. let it cool down;
  • Strictly follow the requirements of the instruction about the mode of operation, otherwise you can overheat the engine;
  • If you do not plan to use the mower in the next month, drain the fuel mixture from the mower, because. к. Over time it breaks down into heavy fractions that will definitely clog the carburetor passages;
  • After draining the fuel, let the trimmer run at idle until it stops, this will help remove the remaining working mixture completely.

Before winter storage, do the following steps:

  • Completely disassemble the mower, rinse and clean all parts you can;
  • inspect the parts for damage; if necessary, repair misalignments, rips, bends and any other malfunctions;
  • Pour enough oil into the reducer and clean the air filter;
  • you can partially disassemble the motor, flush, purge, and lubricate all moving parts;
  • In order to lubricate the piston, you need to unscrew the plug, lift the starter piston to its dead center, pour a little oil into the spark plug hole and a couple of times scroll the crankshaft;
  • if you do not store the mower indoors, wrap the engine with an oily rag.

Remember, the careful observance of the rules will allow you to forget about the fact that badly starts the lawn mower for several seasons.

How to use and store the lawnmower

To ensure that the lawn mower starts well in the future, you need to give it a good storage and operating conditions:

  • during operation, carefully monitor the cooling system, carefully and in time clean the channels in the housing as well as the starter ribs;
  • If necessary, use solvents, kerosene and other detergents for cleaning;
  • do not clean the tool while it is hot. let it cool down;
  • Always follow the operating instructions or you may overheat the engine;
  • If you do not plan to use the mower in the next month, the fuel mixture from it should be drained, t. к. Over time, it breaks down into heavy fractions that will definitely clog the carburetor passages;
  • After draining the fuel, allow the trimmer to idle until it stops, this will help remove any residual working mixture.

Before winter storage, do the following steps:

  • Completely disassemble the mower, rinse and clean all the parts you can;
  • Inspect the parts for damage, and if necessary, repair misalignments, rips, bends, and any other malfunctions;
  • Pour enough oil into the gearbox and clean the air filter;
  • you can partially disassemble the motor, flush, purge and lubricate all moving parts;
  • In order to lubricate the piston, you need to unscrew the plug, lift the starter piston to its dead center, pour a little oil into the candle hole and a couple of times scroll the crankshaft;
  • If you are not storing the mower indoors, wrap the engine with an oiled rag.

Remember, the careful observance of the rules, will allow you to forget about that bad start lawn mower for several seasons.

How to Clean a Carburetor?

Start by checking for an open flame nearby. Do not make repairs indoors. There is a risk of gas leakage.

Loosen the screws with a flathead screwdriver to remove the plastic air filter cover from the engine. Check the clogged filter, remove it with a vacuum cleaner or replace it with a new one (if the condition is not satisfactory).

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You should also remove the internal filter cover, which is under the cover. This is easier to do with a ring wrench, unscrewing the bolts. The air hose is attached to its inside, which must also be removed.

lawn, mowers, start

Finally we get to the carburetor of the unit, which can be disassembled. After disconnecting the fuel hose leading to it from the tank, t.Е. Removing the clamp, the hose goes back, trying to get it off the nozzle. Do the work carefully. After all, if there’s fuel in the tank, it’s sure to spill.

The carburetor is mounted on the engine with two bolts, which require a clutch head to unscrew. When unscrewing the second bolt, try not to lower the carburetor so as not to damage the spring suspension.

Next step. Return the spring. The operation is more convenient to perform from the side where it is attached to the motor. You can now remove the cable responsible for the cover position by carefully turning the carburetor counterclockwise.

After removing carburettor, unscrew bolt that fastens the fuel cell cover.

Cleaning is done with a special liquid or WD-40 and a copper wire, from which the insulation is removed.

Finally, you can remove the plastic float, located under the cover of the chamber, which regulates the level of gasoline, for which you first remove the pin.

lawn, mowers, start

The chamber has to be cleaned of plaque. The carburetor interior should be generously moistened with WD-40 (or equivalent) and wiped dry. After repeating the operation, they clean the copper ducts of the copper piping and blow them out, because their contamination is the main reason why the engine stops or does not start.

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After performing all the described steps, assemble the carburetor in reverse order.

After installing it in place, connecting the hose, air comes out of the fuel chamber. This completes the repair.

After the described manipulations, the equipment will start easily and work steadily.

How do you start to diagnose a brushcutter?

If the lawnmower does not start or immediately stops after starting, you need to check all major components in sequence. The algorithm for checking is as follows:

  • The fuel tank (fuel quality);
  • The spark plug and spark plug passage;
  • Air filter;
  • Fuel filter;
  • Breather plug;
  • Exhaust port.

These components are most often the source of major problems, which can be fixed after a thorough inspection.

Checking the Fuel Mixture

Before starting the engine of a petrol grasshopper, check the presence and quality of the fuel mixture. Don’t save money, don’t be greedy, and don’t “get smart” about it. Repair or replace the piston group will cost you too much (sometimes up to 70% of the cost of a new tool). Prepare oil-fuel mixture strictly according to instructions. Calculate its quantity from real needs. Excessive petrol left after work loses its qualities over time.

Carry out a diagnosis of the plug and the spark plug duct

If the quality of the fuel mixture is beyond a doubt and the lawnmower fails to start, it could be due to a faulty spark plug. An ordinary spark plug wrench (every motorist should have one) and a spare spark plug will do the job.

  • Unscrew the spark plug and wipe it;
  • Dry it thoroughly (don’t burn it);
  • Drain the excess fuel in the chamber through the spark plug hole and dry it out;
  • Clean old candle from carbon deposits with a file or a lady’s file;
  • We set a gap with a distance of 1 mm (it is possible to check it with any coin);
  • Put everything back in place and try to start the grass trimmer.

The channel should be dry for at least 30-40 minutes. Otherwise, there is a risk of re-flooding and a new spark plug.

If the spark plug works, the socket where it is located is completely dry, but the lawnmower does not want to start, lubricate the threaded joint with gasoline. It should be slightly dampened. No matter how great a spark the spark plug gives out, there is simply nothing to ignite in a dry chamber.

If the grass trimmer engine still does not start, you should rule out such a cause as a lack of spark due to poor contact between the spark plugs and the high-voltage wire. If the connection is good, but there is no spark, most likely, you have a “failed” ignition unit. You can’t do without a handyman here, t. к. The part is not repairable, but is sold as a complete unit.

Lawn mower filters diagnostics

Another reason for the gasoline grasshopper to stall can be the air filter. To rule it out, try removing the filter and starting the grass trimmer without it. If it succeeds, you have to change the air filter for a new one, or at least blow out and thoroughly clean the old one.

Gasoline grass trimmer may not start due to dirty fuel filter. This is the next stage of our algorithm. Here we check the condition of the filter element and, if necessary, replace it with a new one. When changing, try not to leave the suction pipe completely without filter, it is forbidden by any instruction manual. Haste can turn into the repair of the engine piston group.

The breather plug and the exhaust port

Often “delicate” brand-name models of gasoline machines do not start and choke due to a clogged breather. The main function of this element is to equalize pressure in the gas tank. When this unit is clogged, a vacuum is created in the tank, preventing fuel supply. You can solve the problem by cleaning the breather plug. A normal needle can be used for cleaning.

Normal operation of a car with internal combustion engines may be impaired if dirt gets into the exhaust port or the muffler grid gets clogged. This problem is common on older models. The problem can be solved by traditional cleaning and removal of the anti-sparking mesh.

complex causes of lawnmower failure

If a step-by-step troubleshooting procedure does not resolve the problem and your lawn mower still won’t start or stops, it’s worth examining the carburetor and engine. A clogged carburetor may be one of the causes of the tool’s erratic operation. Three main problems can be distinguished here:

  • Clogging of channels or nozzles. It is cleaned with special washes or blown with a powerful jet of compressed air from a compressor. Do not use needles and wire, as the passages may be damaged;
  • Worn out carburetor gasket. The solution is to replace the failed gasket;
  • Loss of tightness. To check this indicator, you can use an ordinary household tonometer, replacing the gauge on it with a suitable. Watch the readings: if they do not change. everything is fine, and if the pressure begins to fall, then 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 of the piston group. If you find chips, scratches or scrapes on the piston or cylinder, replace them. Piston rings are subject to mandatory inspection. 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 experts service center.

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How to use and store your lawnmower

For the lawnmower to start well in the future, it is necessary to ensure good storage and operating conditions:

  • During operation, keep a close eye on the cooling system, carefully and timely clean the channels in the housing, as well as the starter ribs;
  • If necessary, use solvents, kerosene and other detergents for cleaning;
  • do not clean the tool “hot”. let it cool down;
  • strictly follow the requirements of the instructions about the mode of operation, otherwise you can 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 disintegrates into heavy fractions, which will definitely clog the carburetor channels;
  • after draining the fuel, let the trimmer run at idle speed until it stops, this will help remove the remaining working mixture completely.

Before storing it for the winter, do the following steps.

trimmer for grass, both electric and with a combustion engine (ICE), is an indispensable tool in the summer and fall for owners of summer houses and private homes. It easily removes weeds, small bushes, and trims the lawn. But, like any technique, grass trimmers fail at the most inopportune moment. To eliminate malfunctions with their own hands, the user of this equipment first needs to determine the cause of their occurrence.

Lawn mowers and electric grass trimmers, if we do not consider the breakdowns associated with the boom and mowing head, malfunctions mainly occur in the area of the engine.

Breakdowns of gasoline trimmers

Typical breakdowns of the gasoline trimmer for grass, which the owners of this unit are most often faced with, are the following:

  • engine failure;
  • Problems with the carburetor;
  • problems with the fuel supply;
  • muffler failure;
  • gearbox breakage;
  • broken starter;
  • problems with the air filter;
  • the breather plug on the gas tank is clogged.
lawn, mowers, start

Faults of electric trimmers

As the structure of an electric mower is much simpler than a power trimmer, the reasons for its failure are few.

It should be noted that it is better to entrust the elimination of some of them to a specialist.

Basically, the grass trimmer stops working normally in the following cases:

  • Faulty electrical cable;
  • The control button is defective;
  • motor stator winding burned out;
  • Broken contact connections on the motor.

One cause of a flooded lawnmower engine.

After examining the main components of the engine and talking to the lawnmower owner we were able to figure out what caused this.

Operator inattention, who may have inadvertently touched the choke control lever and moved it to the “OFF” operating position, which restricted the air supply, implying that the choke was open.

The operator may have misunderstood the meaning of the “ON” and “OFF” position indicators of the choke and became confused.

In short, the human factor is present in all unpleasant situations that occur during the operation of equipment.

While tending their garden, gardeners occasionally come across the fact that the lawn mower won’t start. There are many reasons for tool failure. For proper diagnosis of the problem, the owner of a useful dacha unit needs to know the device and the principle of operation of its individual parts.

Since gasoline grass trimmer belongs to the complex devices, before you start work, it is necessary to carefully study the instruction manual. Very often it is simply ignored, or they get acquainted with it superficially. As a result, when the tool stalls or refuses to start, the question arises. “Why won’t the lawn mower start?” A long seasonal break in the work, improper storage and untimely maintenance of the grass trimmer, will give a lot of trouble to the dacha owner, to eliminate the causes.

Restoring the functionality of electrical equipment

Mowers, inside which electric motors are located, most often begin to be capricious due to oxidation of the contacts. The terminals are covered with a layer of scale from excessive moisture in the room or other storage area. It is also worth checking whether there are no broken wires at the problem areas. Use a multimeter or other type of tester for this operation.

When a set of gardening equipment contains a brush motor, then identify the serviceability of the moving unit. The brushes can wear down quickly, causing a loss of contact. Repair kits are relatively inexpensive and can be easily found at specialty stores that sell spare parts for this equipment.

Malfunctions also occur with asynchronous motors. The phase-shifting capacitors in the brushes are failing. Such a situation is diagnosed at home is problematic. It can be detected by indirect symptoms:

  • a humming sound is heard;
  • at start the case twitches slightly;
  • Motors become significantly hot, even under low load;
  • revolutions decrease.

It is worth carrying out diagnostics of the state of the toggle switch/button and the voltage to the electric motor. When testing the described nodes, and violations in the performance is not detected, then it is unlikely to fix the breakdown of the lawnmower with their own hands. In this case, it will be necessary to use the services of a company service.

Adjusting and tuning the carburetor

Maximal and minimal engine revolutions, even idle speed are regulated by the carburetor. The stable operation of the lawnmower depends on the amount of fuel and air mixture and their ratio. Lawn mower will not start if the carburetor is not adjusted properly. The adjustment of the device for fuel delivery at low speed (L), high speed (H) and idle (T) is regulated by the same-name screws:

  • The chainsaw must run for at least 10 minutes, because the adjustment is made by the hot.
  • Turn the screw H slowly until it reaches maximum rpm, then turn it ¼ turn counterclockwise, reducing the speed of the motor shaft.
  • Idle stroke is adjusted with the screw T, achieving that the grasshopper does not rotate.
  • Screw L is adjusted by first opening the throttle as much as possible and then slowly lowering the RPM to a steady minimum.

After adjustment serviceable carburetor with cleaned filters, checked ignition should provide engine operation. If the carburetor is malfunctioning, after repairing it, the feed system will need to be adjusted again before starting the lawnmower.

Rare breakdowns preventing the lawnmower from working may 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 is about 70% of the product price. To understand the reasons why the lawn mower does not start, will help