Motor window adjustment: carburetor, valve, fuel system. Types and methods for adjusting carburetors

Last years A lot has appeared on sale. useful devices with engines internal combustion (DVS), both domestic and professional. These include mini-power stations, motor-pumps, lawn mowers, motor-cultivators, snow plows. In construction, the use of motobets, welding motor generators, vibrotrampers, vibrators, etc. Most of them have single-cylinder urinous four-stroke engines internal combustion with air cooled. Less often meet diesel enginesBut this topic deserves separate consideration.

The engine is the most complicated and expensive most such devices. Therefore, we consider the characteristics that choose the engine to take into account.

According to the nutrition system, almost all gasoline engines used are carburetor. Most of them use an electronic ignition system, although the cheapest instances have a ignition system in the form of magneto. Electronic ignition is preferable, because It provides a good engine launch in various conditions.

In single-cylinder engines, mainly applied air method cooling. For intensive heat removal in piston group The cylinders are used from aluminum alloys with cast-iron inserts or completely cast cast iron cylinders. Cast iron cast cylinders are more preferred because Motor motor is significantly increased. Although the use of aluminum cylinders with cast-iron inserts is quite acceptable when operating the engine in "home" conditions, for example, in a power station, which is used as a backup with rare power outages. Or in the lawn mower, which is used in the summer of times a week for an hour and other. For professional use, let's say in construction machinery With daily long-term operation, the engine with cast iron cylinders is a prerequisite for its reliable operation.

Essential is the presence of an oil level sensor. The simplest way to "Understand" KVS is its exploitation with low oil level or without oil at all. If there is a sensor, the engine with an insufficient amount of oil in the crankcase simply does not start. Although in all operating manuals, there are calls to check the oil level in the engine before it starts, as the practice of repair shows, not everyone follows this simple and very reasonable recommendation.

Noiseful influence on the price and characteristics of the engine has a gas distribution mechanism applied in it. Currently, three types of SV, OHV and OHC gas distribution mechanism are used in the same-cylinder engines. All three types have been used earlier or are currently used in car engines.

Engines type SV - English Side Valve Abreaturate - Side Location Motors. In the domestic literature, such engines are more often called low-apparatus. In fact, the intake and exhaust valves are located downstairs and side from the cylinder. The camshaft is also located at the bottom and most often has a gear drive from the crankshaft. Single-slide motors with such a layout are released in large quantities all major world Honda manufacturers (Series G), Subaru-Robin (EY Series), Briggs & Stratton, Tecumseh and others. Such engines usually work on low-octane gasoline (not higher than 92) and do not like large revolutions. These engines are inexpensive, reliable, although there are several increased flow Fuel compared to OHV and OHC. Work very well in mini-power stations, where engine turnover is supported fixed (usually 3000 rpm). In most cases, these engines are recommended for home use, although japanese engines This type (Honda, Robin) have a very large motorway and work well in professional techniques.

Interestingly, in the automotive industry, the engines of this type were popular in the 30s of the 20th century. IN soviet cars They lived longer and installed on victory, ZIS, Moskvich 401 and some trucks (mainly gas). The main congenital disadvantages of such a design are associated with a large surface of a complex form of combustion chamber and a ineffective method of operation of a combustible mixture, which increases fuel consumption and thermal losses in the engine. Because of this, engines are prone to detonation fuel mixes And they cannot work on high-octane gasoline. On the other hand simple system Gas distribution and good conditions for lubrication of all its parts are the key to reliability.

Engines type OHV.

Engines type OHV. - english abbreviation Overhead-Valve - Valve Upper Motors. Inlet and exhaust valves are located on top of the cylinder. The camshaft is located at the bottom and most often has a gear drive from the crankshaft (sometimes chain). Valves open and closed with pushers, rods and rocker. Single-slide engines with such a layout in their program have all major Honda manufacturers (GX series), Subaru-Robin (EN Series), Briggs & Stratton (Vanguard), Tecumseh and others. Such engines usually work on gasoline with octane number 95. These engines are somewhat more expensive than SV, very reliable, durable and economical and somewhat less noisy. They are steadily working in a wide range of revolutions, elastic. These properties are due to the mainly postponal form of the engine combustion chamber. They do not like very large revolutions (more than 6500) due to the complex and sufficiently large on the length of the gas distribution system, in which the rigidity of the system and the accuracy of the phases of gas distribution decreases. These engines are recommended for work in professional techniques. They are universal and find the use of almost all types of devices.

In the automotive currently, engines with this gas distribution scheme are most often found on American petrol enginesinstalled mainly on jeeps and pickups and in low-speed cargo diesel engines. Often car engines This type is held a million colometers without overhaul. From domestic engines are most famous (unfortunately not from the best side) engines of the Volga Motor Plant, ZMZ-401, 402, which for several decades were installed on the Volga and other cars, as well as the V-shaped ZMZ-53, which was installed on trucks.

OHC type engines

OHC type engines today are the most common in the automotive industry. What can not be said about the use of this layout in small single-slide gasoline engines. The OHC abbreviation is decrypted as overhead-camshaft, translated from the English - "top arrangement of the camshaft." Such force aggregates Kulachka distribution Vala. Press on the valves directly through the pushers, less often through the rocker. The drive from the crankshaft to the camshaft is most often carried out with a chain or gear strap. The advantages of such an engine - a clear work in a very large range of revolutions, efficiency, reliability, low noise, a big engine test. Such engines can quickly gain momentum and just as quickly drop them, which allows the engine to quickly adapt to a frequently changing load and not reduce the specified power. OHC type engines are used as much as possible. positive traits electronic system Ignition .. The combustion chamber of such an engine has all the advantages of the OHV engine, and the gas distribution system is noticeably easier and does not contain parts that lose the rigidity at high revs or with a sharp change of engine speed.

Single-cylinder engines with such a layout appeared in the program of the main producers relatively recently (in the second half of the 90s) and in the model range there are still quite a modest place. Honda has a GC series, from Subaru-Robin - EX Series, at the Tecumseh model Enduro 70 XL / C G. Most likely the production of such engines will increase in the coming years, the lineup It will expand and they will take a decent position in the production of household and professional equipment with the economy of a harder of their reliability, versatility and economy.

Actually, thanks to these qualities, OHC engines won their dominant position in the automotive industry. They (or their modifications with two DOHC camshafts) are installed on the overwhelming majority modern cars, including all the Zhiguli models.

The carburetor is the element of the motoblock that is necessary to control the streams of air and fuel.

Thus, a motor operation is optimized during a stable load. Like any mechanism, the carburetor needs proper care.

Types and methods for adjusting carburetors

As you know, the motor-block, as well as many other aggregates of this type, works with the help of the engine. Due to the fact that the engine cannot ignore without oxygen supply, the need for the use of the carburetor arises. For the motoblock, the carburetors of two types are used. One of them is rotary, the other is plunger. Naturally, each of the species mentioned has its advantages and disadvantages, the choice depends on the motoblock, its performance and type of work performed.

There are cases when disorders occur in the carburetor (the process is unstable). In such a situation, the carburator requires adjustment. How to adjust the carburetor on the motor-block? This can be done with your own hands, following a certain sequence of actions.

1. Initially, you need to turn the rotation of screws (complete and small gas) to the state of the stop. After that, turn them by one and a half turn.
2. Turn on the motor, let it start and warm up.
3. Do not muffle the engine and place the lever controller to the smallest speed.
4. Next, specify the minimum number of revolutions when the device works stably.
5. After that, start the idle speed to the maximum.
6. Switch the idle to a minimum. Repeat this action, alternating with the previous one, while the engine does not start working without interruptions.
7. Eduge the control lever to the "Gas" position.

Following such an instruction, you can independently configure the carburetor of the motoblock.

Carburetor care, replacement and repair

Sometimes to bring a carburetor for a motor-block to a stable, working condition, not enough adjustment, repair is needed or replacement.

It happens that the air damper of the carburetor is not completely closed. To eliminate this problem, control the operation of the drive. If the hotels are detected - eliminate them. Moreover, given that the carburetor provides fuel supply and, therefore, leads to the movement of the motoblock itself, should closely monitor the state of this part and correctly care for it.

To avoid serious carburetor breakdown, you need to constantly monitor his work. In addition to adjusting the idle, you need to regularly clean the carburetor and replace the wear parts. Since the carburetor interacts with the fuel combustible mixture and air, the cause of its contamination may be either in the first or in the second source.

To make the degree of contamination significantly less, you can use filters that should be cleaned and change as needed. In addition, the quality of fuel is significantly affected. A poor-quality combustible liquid may damage the parts and premature replacement. If needed, the carburetor to the motoblock can be purchased on automotive market or shop. His replacement, adjustment and cleaning also conduct specialists.

This article describes the adjustment of the motoblock, namely the main parts: carburetor, valves and fuel system. The process is not easy, so we also attached several photos and videos.

Motoblock carburetor adjustment

Unstability revolutions engine Motoblock It suggests that the carburetor needs to be adjusted. The need to perform this procedure, as a rule, arises before the start of the agricultural season, when the technique has not been used for a long time, or after it, when the motoblock was exposed to considerable loads for a long period of time.
Before proceeding with the adjustment, you need to warm the engine. The work process is directly as follows:

• Screws regulating small and maximum gas are completely screwed, after which weaken about one and a half turn.
• The motor starts and is heated about 10 minutes.
• The lever that controls the operation of the power plant must be set to a minimum position, but the motor should not stop.
• The screw that regulates the throttle of the throttle will help adjust the minimum revolutions on idlingso that the operation of the motor was stable, without foreign noise and stops.
• Rotation of screws makes it possible to accurately set the amount of combustible mixture, which falls into the motor.
• The tightening of the screw contributes to the enrichment of the mixture, whereas its unscrewing, on the contrary, increases the volume of air entering the engine;

Using a small gas screw, adjust the maximum speed at idle. Similarly, it should be done with minimal turnover, using the throttle valve propeller. The essence of such an adjustment is that the valve screw allows you to adjust the angle to which it is closed;

The lever responsible for managing the motor should be transferred to the position "Gas". If the work of the motoblock still can not be called stable, the full gas screw is adjustable until the ideal course is observed. However, the maximum allowable number of screw revolutions - 2.5.

The accuracy of the adjustment of the carburetor can be determined by the way the ignition candle looks like after a short work under load. If the working mixture is ideal, then there will be no nagar on the candle, nor fuel traces, which speak too poor, or, on the contrary, too rich fuel mixture. It is necessary, however, note that the naar or fuel traces on the candle can speak not only about incorrect adjustment, but also about more serious motoblock problems, among which faulty ignition or cooling system.

Motoblock valve clearance adjustment

Over time, with significant loads, the gap of the engine valves motoblok. Changes. The reason for this can be in the wear of parts. The insufficient distance leads to the fact that the stages of gas distribution are significantly changed, as a result of which a sufficient compression cannot be achieved, power point Works with interruptions and does not enter the stated power. In particularly serious situations, even the deformation of the valves can be observed. If the clearance is too large, the significant mechanical noises are fixed, the gas distribution phases are also significantly changed, the valves are open at a short time, due to which the cylinder is not filled properly, the power drops, failures. The adjustment of the gaps is necessary at once, as soon as the operation of the engine has become incorrect or to occur with significant noise. Ideally, the engine on which the adjustment is conducted must be cooled.

So, you must first get to the flywheel. It is on this detail that the value of the upper dead point is marked. The flywheel is hidden under the casing, and therefore will have to remove it. Oil bath is removed before removing the casing air filter. It is possible to facilitate the task in the process of removing the casing, if you fix all the latches using rubber bands. All bolt connections are unchecked with the key, after which the lid is removed without problems.

On the flywheel you can see the labels that indicate the VTM, as well as the values \u200b\u200bof 5, 10 and 20 degrees. The mark of 20 degrees denotes a fuel mixture injection. The flywheel should be tested under the upper dead point, focusing on the appropriate division. The valve cover is spinning and removed.

In the process of adjustment, you need to use the following tools:

• Screwdriver;
• Caid key to 10;
• Blade 0.1 millimeter thick.

According to the technical passport, the motoblock engine valves gap ranges from 0.1 to 0.15 millimeters, and therefore with the help of the blade you can adjust it very precisely. Nevertheless, it is necessary to pay attention to the fact that some blades have a thickness of 0.8 millimeters, which is unacceptable. The exact value can be found in the micrometer or information on the manufacturer's website. Adjustment is performed as follows:

• Screwdriver;
• We relax the nut, insert the blade and begin to join;
• You should focus on the blade, carefully tightening the nut;
• Adjustment is underway until the free progress is eliminated. He must sit tight enough.
• IN reverse order We collect the casing, install the oil bath in place.

If all manipulations are carried out without errors, the engine will work smoothly and without excess noise.

If fuel is not fed to the cylinder, then, first of all, it is necessary to check whether fuel is enough to the tank. Also need to be controlled whether it comes to the carburetor. To do this, the hose is removed from the input fitting of the device. If we are talking about the K45 type carburetor, it should be pressed onto its thoroughtress so that the fuel began to pour out through the drainage hole.

If fuel does not fall into the carburetor, then you need to unscrew the fuel supply faucet, fully disassemble it and remove the mud clusters from the mechanical cleaning filter. To achieve maximum purity, all composite elements It is necessary to treat gasoline. The fuel faucet is going and returns to the previous place.

If the fuel comes into the carburetor, but it is not supplied to the cylinders, it is necessary to check the correctness of the operation of the fuel valve, as well as the presence of dirt on loaf.

To deal with the carburetor gasoline Motoblock. The KBB-5 type, it is necessary to remove it from the motor and pour the fuel from the float chamber. Through the fitting (see Figure), with the help of which the gasoline is conducted, it is necessary to submit an air mixture, after setting the carburetor to the working position. The passage of air should go unhindered, and when the carburetor is reversed, it is completely stopped. These features are talking about the full performance of the part.

Fig. 2. KMB-5 carburetor

Details in Figure: 1 - fitting, sliding fuel; 2 - upper case; 3 - throttle of choke; 4 - Needle of small gas; 5 - fatter; 6 - lower case; 7 - air damper; 8 - screw fixing the screed; 9 - needle of maximum gas; 10 - spraying element; 11 - float; 12 - Fuel supply valve.

The fuel level inside the float chamber can be adjusted using the float tongue. Ideally, it should vary from 3 to 3.5 centimeters.

To perform the produce of loans, you must unscrew the screws that are responsible for full and small gas.
Cleaning the parts of the carburetor begins to turn off the screws holding the upper case. The lower body is removed, the fuel supply valve is washed with gasoline, and the dirt from the jaws is blowing out the pump. It is necessary to check if the float is intact. Using in the process of cleaning the rags are categorically impossible.

After completing cleaning, the housing is connected. It is necessary to control the spray tube clearly passed into the hole located on the upper case. Open the throttle and check how clearly the assembly is made. Screws fixing the top housing are tightly tightened. After the assembly process is fully completed, the carburetor should be adjusted. This will significantly improve the performance of the motoblock with hinged equipment Since the perfect setting of all its details is required for correct operation.

If the DM 1.08.100 carburetor is installed on the motor-block motor, then the technique of its adjustment will be this:

• A screw 10 should be wrapped (Fig. 3) of small gas to full stop and unscrew from itself to the half-turn.
• Then you need to spin the screw 9 of the total gas completely to turn it into 2 turns.
• Unscrew the screw 4 (Fig. 4) of the minimum speed of the engine directly until the lever is stopped into the tide of the carburetor housing and wrap at 2 turns.
• Start the engine motor block, then adjust stable work At maximum speed after warming up 9.

Do not allow the engine control lever, transfer it to the position of the minimum gas (revolutions) and by turning the screw 10 to set the stable momentum of small gas.

Fig. 3. DM Carburetor 1.08.100

Fig. 4. DM Carburetor Outside

That's basically it. The main points of adjustment of the main parts of the motoblock are considered. Adjust your motoblock with pleasure!