The Walk-Behind Tractor Smokes Black Smoke And Does Not Pull

Malfunctions of the walk-behind tractor Tips for identifying the causes of malfunction of the walk-behind tractor and their elimination

Unstable idle speed

– Possibly too large clearance of the gear cover. Make a gap of 0.2-0.5

Walk-behind tractor malfunctions

In this thread, we will disassemble the malfunctions of motoblocks and cultivators of all brands, Salute. Neva, Bison, etc., and their removal and repair. Most of the problems are typical for all types of motoblocks, their engines and other components.

Engine won’t start

– If the engine is tilted, must be placed horizontally.

– The fuel may not be supplied to the carburetor. It is necessary to disassemble and purge the fuel system with air.

– The filter may be clogged. The filter needs to be replaced or cleaned.

– The outlet in the gas cap may be clogged. Needs to be cleaned.

– Maybe it’s the candle. It is necessary to check the connection of the wires, the engine stop buttons, unscrew the spark plug and clean. Replace if necessary.

– Magneto failure possible. Replace.

Engine runs intermittently, stalls

– Engine may not yet warm up. Need to warm up

– Candle contamination possible. It is necessary to clean the candle by removing carbon deposits.

– The end of the wire does not fit snugly against the candle. Press the end of the wire firmly against the candle.

– Failure of magneto. Replace.

Engine power dropped

It often happens that a previously serviceable walk-behind tractor that has served for several years suddenly loses power.

– If the power drops after long-term storage, it is possible that the walk-behind tractor was stored with a wet carburetor and fuel system, which led to deposits. In this case, you can start the engine and let it work, often, after these actions, the power is restored. If you have skills, you can disassemble and clean, if there are no skills, it is better to contact the service.

– The carburetor may be clogged. Clean

– Clogged benzo hose. You need to purge.

– Possible loss of crankcase cuff operability. Remove the casing and gearbox cover, inspect the oil seal.

– Carbon deposits on the cylinder, muffler. Clean.

– Clogged air filter. Clean.

– No compression. Change piston rings, cylinder, piston.

Smokes the walk-behind tractor

White smoke is pouring out of the walk-behind tractor, it starts to work in a bucket.

Why does the walk-behind tractor stall under loads?

The Walk-Behind Tractor Smokes Black Smoke And Does Not Pull

A common problem is that the technician stalls after 5 minutes of work. Often the reason is a fuel supply failure and ignition problems.

If the equipment stalls during operation, you need to check how well the fuel is supplied:

  1. The candle is taken out and viewed. It is overdried, this indicates a lack of fuel;
  2. There must be enough fuel in the gas tank for the normal functioning of the machine;
  3. The condition of the fuel cock is examined. It can be simply blocked. Sometimes it is enough to open it for further use of the unit.

The walk-behind tractor starts up and stalls if there is a problem with the ignition. First you need to check the candles. Wet items indicate breakage. It is necessary to re-adjust the ignition system of the equipment.

Reconfiguration is done as follows:

  1. The cover is removed, which protects the parts of the ignition system;
  2. The engine flywheel turns until the contacts open in the magneto;
  3. A special probe measures the gap from the anvil to the hammer;
  4. The flywheel turns until the piston is compressed. The latter must reach its peak;
  5. The flywheel turns again until the characteristic knock, which will indicate the operation of the freewheel;
  6. The flywheel turns in the other direction until the mark of this element coincides with the mark on the unit body;
  7. The gap from the break contact to the cam is set at 0.3 mm;
  8. The cam is fixed with a screw, which is located above the element, and the protective cover is installed in the equipment case.

If the above steps are performed correctly, the walk-behind tractor will not stall under load. When tilted, vehicles may stall if there is not enough fuel in the gas tank. The unit must be installed straight, remove the starter rope. If the engine starts, you need to fill the fuel tank.

Why does the walk-behind tractor start up and stall?

If the equipment starts up and immediately stalls, this may indicate the following problems:

  1. There may be a large distance between the electrodes, problems with contacts in the electronics, the spark plug is dirty. First, the candle is cleaned. After that, the integrity of the wires is checked. The normal distance between the electrodes is set;
  2. The carburetor may be dirty, too little fuel is supplied. Sometimes it is necessary to change the fuel and reduce the amount of oil. The carburetor is dismantled, disassembled and thoroughly cleaned;
  3. If the unit does not pick up speed, this indicates a lack of fuel. Gasoline can simply spill. The defect must be eliminated or the fuel tank replaced;
  4. The walk-behind tractor does not develop speed if the gearbox breaks down. This is indicated by the presence of external sound from the gearbox. The malfunction is eliminated by replacing the oil with which the units are lubricated.

Malfunctions of walk-behind tractors: why it stalls, does not develop momentum, do it yourself repair

The motoblock is a useful household unit that greatly simplifies land and housework. As with any other equipment, units can break. But it is quite possible to repair a walk-behind tractor engine with your own hands, following simple recommendations.

Why does the walk-behind tractor work intermittently?

There are other issues worth considering:

  1. The motor block engine hits the return line. The reason is often poor fuel use. It will not be enough to replace the fuel. The pump and fuel supply hoses are flushed;
  2. The technique works in jerks. The engine does not fully warm up. The motor must be turned off, wait for it to cool completely. Then restart it and warm it up for at least ten minutes;
  3. The engine does not pull, therefore the motor power decreases. The filter system is checked and cleaned. The problem can be provoked by wear of the magneto ignition. In this case, the part is replaced.

Owners of both petrol and diesel vehicles may face such problems. Regardless of the specifics of the breakdown, it is necessary to urgently stop using the unit and fix the problem.

Why does the walk-behind tractor shoot at the muffler?

Sometimes the operation of the equipment is accompanied by unusual sounds from the muffler. The walk-behind tractor smokes and stalls. To eliminate such a malfunction, you must first determine what caused it.

Such problems can occur in the following cases:

  1. Excessive engine oil in the fuel. The remaining fuel is drained, the fuel pump and hose system are flushed, new fuel is poured;
  2. Incorrectly exposed ignition. It is necessary to check how correctly the gap between the electrodes is set;
  3. The fuel in the engine cylinder does not completely burn out. In this case, it is necessary to disassemble the piston system, wash and dry the cylinder well, adjust the carburetor.

In the above cases, it is not difficult to repair motoblocks on your own. It is important to strictly adhere to the algorithm of actions.

Why does the motor block engine start badly when hot?

Appliances can stall when heated. This problem is relatively easy to fix. This is often provoked by the fact that an excessive amount of air is supplied to the carburetor. It mixes with gasoline and engine oil, acts as a carburetor cooler. So the temperature of the latter is much lower than the temperature of the motor-block engine.

To fix the problem, you need to follow a certain algorithm. It is important to start the engine. To do this, follow these steps:

  1. When starting the engine, the gas trigger is squeezed halfway;
  2. Do not regularly press the gas trigger, as this can provoke engine flooding;
  3. After starting the engine with half of the pressed trigger, the gas must be thoroughly gassed. Then you can continue to work.

Simple actions will prevent an increase in the load on a heated engine, the main elements and systems are not subject to increased wear. The listed methods will allow you to eliminate the malfunctions with the unit. They are equally effective for owners of the following brands: Agro, Honda, Neva, Kaskad.

The reasons why the injection engine smokes black?

The injector is nothing more than an electronic carburetor. If in the carburetor the composition of the fuel mixture changed due to mechanics and pressure drops, then in the injector electronics does this.

Our main assistant in diagnostics of an injection engine is a lamp on the check engine dashboard. If this lamp on the dashboard glows and black smoke is observed from the exhaust pipe, then you have a direct path to diagnostics. After diagnostics, you will recognize the failed sensors and quickly restore the engine.

Everything becomes more complicated when the diagnostic lamp does not indicate a malfunction, and the engine smokes like a steam locomotive. In this case, the mechanical part failed, and computer diagnostics will not give anything, you have to work with your hands.

Why does the engine smoke black and how to fix it?

Good day. The topic of today’s article is why the engine smokes black smoke? The article discusses the main reasons for the appearance of black smoke in carburetor, injection and diesel engines, and also provides a troubleshooting technique.

How to find out which carburetor system is malfunctioning?

  • If black smoke is observed both at idle and at rpm, the air filter is most likely clogged or the fuel level in the float chamber is higher than recommended.
  • If Black Smoke is observed only at idle, either the air jet is clogged or the adjustments are knocked down.
  • If black smoke is observed while driving at medium speed, the main air and fuel jets should be checked
  • If black smoke is observed at wide open throttle, the economizer system is faulty.

Any malfunction of the carburetor (except for heating at idle speed) requires its disassembly and prevention.

We agreed to check the air filter, and if it is in order, we will repair the carburetor.

The reasons why diesel smokes black?

Diesel engines are available with a mechanical injection pump and electronically controlled so-called. Fuel injection systems (comon rail). I’ll make a reservation right away, I don’t consider old engines without a turbine, since this is an atavism and they are already extremely rare.

The most common reason why a high-quality diesel fuel smokes is to be treated by replacing it with a normal one!

How does the injector meter fuel?

An important part of the injector is the fuel rail with injectors. A constant gasoline pressure is maintained in the rail (3.0 bar for most vehicles). Do the nozzles open? Electrical impulse, for the calculated time and as a result of this, a precise dose of petrol is injected.

The calculation of the opening time of the injectors and the ignition time of the mixture is carried out by the engine control unit, based on data from the sensors.

If the diagnostic lamp does not light up and the injection engine smokes black, the diagnostics begins with checking the fuel pressure in the fuel rail. This is done as follows:

If the fuel pressure in the rail differs from that set by the manufacturer, the fuel pressure regulator must be replaced.

If the fuel pressure is normal, remove the rail and check the tightness of the injectors. The fact is that with wear or clogging, they do not completely cut off the fuel supply and gasoline pours into the engine even with closed injectors. As a result, the mixture is enriched and the engine smokes.


  • If the lamp is on, check the engine, we go for diagnostics
  • If the lamp is off, check the fuel pressure and the serviceability of the injectors

The carburetor prepares the fuel mixture for the engine.

The optimal fuel mixture is 1 liter of fuel for 15 liters of air. Rich, rich, normal and lean mixtures are used depending on engine operating conditions. For example:

A rich mixture is used to start a cold engine, since part of the fuel condenses on the walls of the cylinder and the intake manifold, as a result, the working mixture in the cylinder will be optimal for ignition.

At idle, a rich mixture is used to ensure stable and uniform engine operation.

At partial load (opening the throttle to 80%), a lean mixture is used, this is done for better fuel economy, since in which case it is possible to increase the power by opening the throttle valve fully.

In the maximum power mode (throttle valve fully open), the optimal fuel mixture is applied.

The lean and optimal mixture burns with virtually no smoke! The rich mixture burns with visible black smoke, the rich mixture smokes like this:

It is obvious that when the mixture is enriched, the carburetor is faulty or the air filter is catastrophically clogged.

A little theory about the carburetor device:

A modern carburetor is a rather complex mechanical device in which several systems are combined:

The idle system prepares a rich mixture at low vacuum downstream of the throttle valve. The operation of this system is provided by 2 air and fuel jets, in fact, the idle system is a separate simplest carburetor.

The transient system allows the engine to run from idle to partial load before the main metering system starts operating.

The main dosing system provides mixture preparation in all engine operating modes, except for idle and transient modes. The accelerator pump also belongs to the main dosing system.

Why does the walk-behind tractor work intermittently?

Among other typical malfunctions of the walk-behind tractor, a number of such breakdowns can also be distinguished:

  • The motor of the unit hits the return line, this indicates the use of low-quality fuel for refueling the unit. In this case, you will have to not only replace the fuel, but also thoroughly flush the fuel pump and fuel supply hoses;
  • The walk-behind tractor works in jerks, the reason for this lies in insufficient heating of the motor. Be sure to turn off the engine, wait for it to cool completely, and start the engine again, giving it at least 10 minutes to fully warm up;
  • The motor-block motor does not noticeably pull, the engine power has decreased in this case, you need to check and, if necessary, clean the air and fuel filter. Another reason for this breakdown lies in the wear of the magneto ignition system. It is best to replace the part right away without trying to repair it.

The owner of both a gasoline and a diesel walk-behind tractor is equally often faced with this kind of malfunction. In any case, immediately stop working with the machine and repair the breakdown as soon as possible.

Why does the walk-behind tractor shoot at the muffler?

Often, when working with an agricultural unit, loud uncharacteristic sounds from the muffler are clearly audible. At the same time, the walk-behind tractor also smokes and stalls. To be able to fix a malfunction with your own hands, you need, first, to determine its essence.

Most often, the walk-behind tractor shoots at the muffler due to a number of the following problems:

  • An excess of engine oil in the fuel mixture, in this case, you need to drain the remaining fuel, flush the fuel pump and hoses, and fill in new fuel with less oil;
  • Incorrectly set ignition, if the mechanism works with a delay, this leads to the appearance of atypical shots, which are clearly audible in the area of ​​the muffler. In such a situation, you should immediately set the correct gap between the electrodes of the ignition system of the walk-behind tractor;
  • Incomplete combustion of fuel in the engine cylinder. Repairing a walk-behind tractor engine in this case means disassembling the piston group, thoroughly washing and drying the engine cylinder, and adjusting the carburetor of the walk-behind tractor.

Repair of all of the above breakdowns does not require special skills and great experience. The most important thing is to act strictly in accordance with the operating instructions for the agricultural unit.

Why does the walk-behind tractor stall under load?

Almost every owner of a walk-behind tractor, regardless of the brand and model of the agricultural unit, has encountered a problem in which the walk-behind tractor starts up and stalls after 5 minutes of operation. The main reasons for this breakdown lie in the problems with the fuel supply and the breakdown of the ignition system of the machine.

As practice shows, if the walk-behind tractor stalls during operation, then its owner should immediately inspect the details of the fuel supply system. First of all, unscrew and look at the spark plug if it is completely dry, then this indicates that fuel does not enter the engine cylinder. After that, you need to make sure that there is a sufficient amount of fuel in the fuel tank. If there is gasoline and it is enough for operation, inspect the fuel cock; it is possible that it is in the closed position. To start the walk-behind tractor, just open the fuel cock and continue working with the unit.

Another reason why the walk-behind tractor starts up and stalls after 5 minutes of operation is a breakdown of the ignition system. To determine that the unit is faulty for this very reason, just take a look at the candles if they are wet, it means that the malfunctions appeared in the ignition system of the walk-behind tractor. The best way out of this situation is to re-adjust the ignition system of the unit. All actions, in this case, must be performed in this order:

  1. Remove the cover that protects the elements of the ignition system;
  2. Turn the flywheel of the motor until the contacts open in the magneto;
  3. Using a special dipstick, measure the gap between the anvil and the hammer of the walk-behind tractor ignition system;
  4. After that, turn the flywheel until the piston of the walk-behind tractor is compressed. In this case, the latter must reach its highest point;
  5. Turn the flywheel again until you hear a characteristic knock, which means that the overrunning clutch has worked;
  6. Then turn the flywheel in the opposite direction so that the mark on it coincides with the mark on the walk-behind tractor;
  7. Set the gap between the break contact and the cam to be 0.3 mm;
  8. Finally, fix the cam with the screw located on top of the part, and install the protective cover back into the walk-behind tractor body.

After the above steps, the walk-behind tractor will no longer stall under load. The main thing in the event of such problems in the future is to try to eliminate the breakdown as quickly as possible so as not to give in to increased wear on the main mechanisms of the walk-behind tractor.

Also, the household unit often stalls when tilted. This indicates an insufficient amount of fuel in the fuel tank. If you put the unit in a horizontal position, pull out the starter rope, and the engine will start, which means that you will need to add gasoline to the tank.

Repair: why the walk-behind tractor stalls under load, shoots at the muffler, works intermittently, and more

The motoblock is one of the most useful household units. Even a simple and not particularly powerful machine can significantly facilitate the care of the garden and the surrounding area. At the same time, the walk-behind tractor is a technique that tends to break. Let’s look at the most common breakdowns of an agricultural unit, their causes and methods of elimination on our own.

Motoblock starts up and stalls reasons and repair

Repair of walk-behind tractors if they start up and, after a few seconds, stall, you must start by looking for the main causes of this malfunction. To do this, you need to inspect:

  • Candles, wires and electrodes in most cases, the unit starts up and immediately stalls due to too large a gap between the electrodes of the ignition system, poor contact between the wires, as well as a dirty spark plug. Repair should begin with cleaning the spark plug. If this does not help, then you need to check the integrity of the wires. If this did not bring the desired result, then it will be necessary to re-set the gap between the electrodes of the ignition system;
  • Carburetor for contamination and sufficient fuel supply If you have used low-quality gasoline and have added too much engine oil to it, you will need to change the fuel and reduce the amount of oil. In addition, you need to dismantle, disassemble, and thoroughly clean the carburetor;
  • The presence of gasoline in the fuel tank if the walk-behind tractor is not picking up speed, then this often indicates a lack of fuel necessary for the engine to work properly. Very often, motoblock owners are faced with a problem in which gasoline spills through a small hole or crack in the car’s fuel tank. In this case, you need to try to patch up the defect, and if it was not possible to do this, you will need to completely replace the tank of the walk-behind tractor.

Another less common cause of a breakdown in which the walk-behind tractor does not develop speed is a gearbox malfunction, which is evidenced by a third-party sound from the gearbox. To fix the breakdown, you need to change the oil that you use to lubricate the unit.

The engine of the walk-behind tractor does not start well when hot

The question of why the motor of the walk-behind tractor stalls when heated is quite simple to solve. The whole essence of the problem lies in the excess of air supplied to the carburetor of the walk-behind tractor. Part of it is mixed with a mixture of gasoline and engine oil, and the second part cools the carburetor. As a result, the temperature of the carburetor becomes much lower than the temperature of the engine of the unit. This problem is observed only during the operation of the walk-behind tractor. When its engine is turned off, the carburetor, on the contrary, lends itself to heating from the side of the hot walls of the engine.

During the heating of the carburetor of the walk-behind tractor, the remaining fuel begins to actively evaporate, filling all the voids in the walk-behind tractor device, including the air filter and the intake manifold. This leads to the complete disappearance of fuel, due to which the walk-behind tractor does not start when the engine is heated.

To fix this problem, it is necessary to act in a certain algorithm every time the walk-behind tractor is started. Your main task is to achieve a combination of the mixture so that the engine can start. This will require:

  1. In the process of starting a hot engine, squeeze the gas trigger halfway;
  2. Do not try to pull the gas trigger over and over again, otherwise this will only aggravate the situation, since during frequent pressing of the gas trigger, the fuel pump will supply new portions of fuel to the carburetor, which will lead to flooding of the engine;
  3. After several attempts to start with the gas trigger half pressed, you will start the walk-behind tractor engine, after which you will need to gas it 23 times and continue working.

This procedure will eliminate the increased load on the hot motor, due to which the main parts and mechanisms of the walk-behind tractor will not succumb to excessive wear.

All of the above methods will help to effectively cope with typical breakdowns of the most famous manufacturers of motoblocks. They are equally successfully used by the owners of agricultural units of the brands Honda, Agro, Kaskad and Neva.

Fuel equipment

Diesel also has black exhaust smoke as a result of fuel pump malfunctions, leaking diesel injectors or too much advance of the injection angle. With a large advance (early fuel supply), strong detonation and increased noise may occur when the engine is operating in different modes. In the list of breakdowns of fuel equipment, wear of nozzles and a violation of the shape of the spray pattern, failure of the speed regulator in the high-pressure fuel pump are noted. Prolonged driving on low-quality fuel quickly puts the injection pump out of action, since low-grade diesel fuel does not provide proper lubrication to the pump.

Low compression

In the list of the main reasons that diesel fuel does not burn completely, there is a drop in compression in the cylinders. At low compression, the diesel engine has a distinct black exhaust. In a diesel engine, the pressure generated at the end of the compression stroke plays a key role. The efficiency of self-ignition of the fuel-air mixture depends on the temperature of the compressed air at the time of fuel injection. At low compression, the temperature for full combustion will not be enough, and the problem is most pronounced at negative temperatures overboard. A low compression diesel engine will often not start in winter.

Black smoke from diesel exhaust pipe

Diesel often smokes black smoke as a result of incomplete fuel combustion. The color of the exhaust is caused by hydrocarbons that are not burnt in the cylinder. These elements then turn into soot. The combustion efficiency of the mixture depends on the exact ratio of oxygen to fuel. Lack of oxygen or an excess of diesel fuel equally lead to black diesel exhaust.

The black smoke from a diesel engine is clearly visible during the day as it contains an abundant amount of soot particles. The smoke is dirty and heavy. It is the soot that is a direct indication that the diesel fuel in the cylinder does not burn completely. Diesel in this case smokes with thick black smoke, increased consumption of diesel fuel is noted. There are problems with starting the engine on cold, the diesel will not start on hot. The operation of the unit is extremely unstable in all modes, the toxicity of exhaust gases increases greatly, power is lost due to large deviations in the composition of the working fuel-air mixture from the optimal parameters.


Diesel black exhaust can also occur as a result of problems with the turbocharger, which does not develop the necessary boost for efficient combustion. Lack of tightness in the intake tract often results in black smoke coming from the exhaust pipe of a diesel engine. In this case, such smoke can be seen at the moment of gas re-gas. On a turbodiesel, the fuel supply during re-gasification increases, but the boost pressure occurs with a delay as a result of the inertial rotation of the turbine. For this reason, there is a lack of air in the cylinder for full combustion of the fuel-air mixture, as a result of which the diesel engine emits a lot.

Diesel exhaust black: the main reasons

One of the most harmless causes of black smoke is the poor quality of diesel fuel (cetane number of fuel) in the fuel tank. The color of the exhaust is gradually normalized after an immediate transition to the best diesel fuel.

Diesel with poor fuel usually smokes gray-black exhaust. Also, the reason for the appearance of a small amount of soot in the exhaust is a clogged exhaust system of the engine. In other cases, the presence of black smoke from a diesel exhaust pipe indicates that:

  • There are problems in the fuel or air supply system of the diesel engine;
  • The conditions for optimal combustion of the mixture are violated (often due to wear of the CPG);
  • Possible malfunctions of the gas distribution mechanism;

Soot formation and effects

When black diesel exhaust smoke appears as a result of malfunctions of the high-pressure fuel pump, diesel injectors, as well as in the absence of an optimal injection advance angle, increased soot formation occurs. The diesel particulate filter suffers from its excessive amount. Soot also seeps into the engine oil and quickly contaminates the engine. There is a violation of heat exchange, the piston rings quickly coke, the filters are clogged.

Blockage of the internal combustion engine oil channels leads to a decrease in pressure in the lubrication system and increased wear of engine parts. A disturbed thermal regime can cause burnout of both pistons (CPG) and valves (timing). Excess unburned fuel through such burnouts gets into the engine oil. The fuel in the oil immediately reduces its viscosity, the lubricant becomes ineffective, and the antiwear properties of the additives in the engine oil are lost.

Parts of the cylinder-piston group get hit. The cylinder walls are the first to suffer, as the diesel oil washes out the oil, as a result of which seizures appear on the cylinder mirror. The wear of the rest of the engine parts is also greatly increased. It is problematic to operate a diesel engine with the indicated malfunction, and further driving will quickly disable the internal combustion engine completely, and overhaul of the diesel engine will be required.