The carburetor solenoid valve, also called the idle air regulator, is a component of the carburetor designed to save fuel consumption in carburetor internal combustion engines. A malfunction of the solenoid valve and its incorrect operation can lead to increased fuel consumption and to the fact that the car engine stalls at idle.

Operating principle of the carburetor solenoid valve

The carburetor solenoid valve is used to regulate the supply of the fuel mixture bypassing the throttle valve, which is controlled by the accelerator pedal. At idle, fuel enters the ICE inlet manifold through a separate channel. This is why the solenoid valve is also called the vehicle idle air control valve. The main purpose of the valve is to stop the fuel supply in inertial modes, which, for example, allows engine braking and coasting.

In gasoline carburetor engines, the valve is installed directly in the carburetor and is part of the car's forced idle economizer system. The valve is controlled by the system's electronic control unit; when a pulse is received, the valve needle retracts and closes the fuel supply, bypassing the valve. After the engine is started, power is supplied from the control unit and the valve begins its operation, which consists of two strokes:

• on the first stroke, the valve opens, as a result of which air enters the chamber and mixes with fuel;
• at the second stage, the air channel is closed and the fuel channel is opened, as a result of which the fuel-air mixture enters the engine.

The movement of the valve shut-off needle is carried out by incoming electrical impulses from the control unit. As soon as the gas pedal is pressed, the valve moves to the open position and the needle extends. At idle, the valve goes to the closed position at engine speeds above 2100 RPM. The transition to the open position occurs when the engine speed drops below 1900 RPM. Closing and opening the valve allows you to regulate the flow of the fuel-air mixture into the engine and, accordingly, save gasoline consumption by up to 5%. Also, the operating principle of the valve makes it possible to reduce wear on the piston group. The immediate consequence of the operation of the solenoid valve is a reduction in emissions of harmful substances (CO) into the atmosphere, which increases the environmental friendliness of the car.

Signs of a malfunctioning carburetor solenoid valve

A malfunction of the carburetor solenoid valve can be determined by several characteristic signs:

• the engine regularly stalls at idle;
• the engine stalls when coasting;
• Fuel detonation occurs after the ignition is turned off.

The instability of the solenoid valve can also be determined by a drop in engine speed when an additional load is turned on (car radio, headlights, etc.). Thus, the main sign of a valve malfunction is unstable engine operation in idle mode.

Valve check

Checking the solenoid valve for correct operation can be done in three different modes:

• when the engine is idling;
• when braking the engine;
• after turning off the ignition.

The general serviceability of the valve can be checked after turning on the ignition. To do this, you need to increase the engine idle speed to 2100 RPM. After crossing this mark, a characteristic click should be heard, which means that the valve has closed. After this, you can lower the speed, as soon as its number reaches 1900 RPM, a click should be heard again, meaning that the valve has opened.

When braking with the engine while the gear remains engaged, the valve should not open, even if the engine speed has dropped below 1900 RPM. If a click is heard at this moment, the valve is not working properly.

If detonation and vibration occur after the engine ignition is turned off, this means that the valve does not close the idle jet and the fuel mixture enters the engine, which also indicates a malfunction of the solenoid valve.

You can also simply check the valve by disconnecting the power cable with the engine running. The motor should stop immediately after disconnecting.

You can check the valve by completely disconnecting the device from the carburetor. After dismantling the valve, you can connect it to the battery, after which you should hear a click and the valve needle should retract into the device. After turning off the power, you should hear a click again and the needle should move out.

The problem with the solenoid valve may lie not only in its malfunction, but also in the electronic control unit and in the wires. You can check the functionality of the wire using a multimeter (12 V ± 10%).

Checking the functionality of the control unit will require connecting the valve to the battery using an additional wire. A standard voltage control light is also required. First you need to disconnect the supply wire from the valve and connect it to the positive terminal of the battery. An additional wire is also connected to the battery positive. After this, you need to start the engine, at the cut-off of 900 RPM the warning lamp should light up, and after reaching 2100 RPM it should go out. When reduced to 1900 RPM, it will light up again. If these indicators are met, but the engine stalls at idle, then the fault is probably in the valve control unit.

Installing the carburetor solenoid valve

When replacing a solenoid valve, it must be adjusted correctly so that the incoming fuel-air mixture meets the required parameters. The installation is carried out with the engine running, as this will allow you to accurately adjust the valve. In a carburetor, the valve is located under the air filter cover, so to remove a faulty solenoid valve, you must first remove the air filter cover.

First, you need to hand-screw the valve into the carburetor seat and put on the standard wire that connects the valve to the control unit. After this, you need to start the car’s engine, which will stall and possibly try to stall. If the engine still maintains speed, then further tightening of the valve into the carburetor is done using a wrench (13 or 14 depending on the type of valve). Further installation is carried out in the following way:

• the key is turned 1–2 cm clockwise, after which the wire is removed;
• if the car engine does not stall, then the wire is put on again and the procedure is repeated;
• As soon as the engine stalls after removing the wire, the valve is installed correctly in the carburetor.

Installation of the solenoid valve must be carried out carefully so as not to damage the fuel nozzle and seat in the carburetor. During the installation process, the size of the fuel mixture entering the engine is automatically adjusted, after which tripping and detonation stop. For precise adjustment, you can tighten the “quality” and “quantity” screws on the valve.

If, after tightening the valve several times and disconnecting the wire, the engine still does not stall, this means that fuel is entering the engine bypassing the solenoid valve and it is necessary to look for a malfunction in the fuel supply system.

Many owners of cars with carburetor engines, after the solenoid valve fails, simply block its operation or dismantle it, which solves the problem with the engine, which stops stalling at idle. However, such actions are only at first glance the right decision. Blocking the solenoid valve significantly increases fuel consumption (up to 5%), which will cost much more in the future operation of the vehicle.

To control the fuel supply, a gas equipment solenoid valve is provided in the gas equipment system on the car. Its main function is to open and close the flow of gas from the cylinder to.

In this article we will look at the types, design, installation options, main faults and methods of repairing the solenoid valve of a gas cylinder installation.

The 2nd generation HBO device on a carburetor engine provides for the presence of two electric valves:

1. gasoline (for supplying/cutting off standard fuel);
2. gas valve (EGV).

The diagram of the gas system for injection engines (GBO 2-4 generations), where gasoline is supplied to the cylinders using injectors, assumes the presence of only a gas valve.

Gas and petrol valves

Design and principle of operation

The design of all EGCs is identical:

• Electromagnetic coil (solenoid).
• Sleeve (core tube).
• Spring.
• Core (anchor).
• Rubber cuff.
• O-rings.
• Valve body with seat.
• Inlet and outlet.
• Coarse fuel filter.

Gas valve device

The operating principle of all devices is also the same. The only difference is that the solenoid valve is controlled using the gas system ECU (electronic control unit). In the second generation, signals to the EGC come from the equipment power button.

If there is no power to the coil contacts, the core, under the influence of a spring, presses the cuff to the seat, so the valve is in the closed state. As soon as voltage (12 V) appears at the solenoid terminals, under the influence of the magnetic field the armature moves along the sleeve, thereby unlocking the valve.

Installation and connection

According to the type of location, gas valves are:

1. Remote;
2. built-in

A remote gas gas solenoid valve is usually mounted in the engine compartment of a car, or placed directly on the gas reducer through an adapter. Built-in, located in the evaporator housing.

Built-in and remote electrovalves

Sometimes, for greater safety, two valves are installed at once, after the multivalve (in the flow line before the evaporator) and on the gearbox.

The connection is made using gas equipment wiring, according to the diagram that is included in the gas equipment kit. When the harness is laid from the control button to the solenoid. During the process, the cable runs from the HBO control unit to the valve. There is no difference where to connect the terminals on the coil.

Possible faults

Often, due to breakdowns of the gas electric valve, malfunctions occur in the operation of gas equipment. Such as:

• Unstable engine operation at idle;
• Gas system failure due to lack of pressure.

Causes of malfunctions due to which the unit does not hold and allows gas to pass through:

1. clogged;
2. jamming/sticking of the core;
3. wear (loss of properties, weakening) of the return spring;
4. failure of the rubber seal or valve seat;
5. coil malfunction.

In a carburetor circuit where gasoline electric power is present. valve, in addition to everything else, increased consumption/leakage of gasoline or failure of the engine to operate on standard fuel may be added.
You can detect a leak by removing the gas hose from the carburetor with the car running or by purging the valve (in a closed state) with a pump/compressor.

Do-it-yourself gas turbine solenoid valve repair

To repair the solenoid valve, you must first stock up on a repair kit and a set of tools.

However, in some cases, regular cleaning/flushing of the solenoid armature helps.

So, to repair a gas valve, the first step is to tighten the valve to shut off the fuel supply from the cylinder. Then drain the remaining gas from the supply line and remove the unit.

• cover the filter element and remove the element itself;
• coil;
• solenoid sleeve with core.

After cleaning all the parts, you need to troubleshoot them and, if necessary, replace them.
It is important that if the system uses copper lines, oxide particles from such tubes are most often the cause of sticking of the solenoid armature.

Also, do not forget about the frequency of replacing the filter element. It is recommended to change the filter once every 7-10 thousand km. mileage

It is advisable to check the resistance of the coil with a multimeter and compare the parameters with those indicated on its body (the norm is about 9-13 Ohms). In addition, rubber seals and the valve seat have their own resource.

Sit back, we will talk about one of the most mysterious parts of the scooter - the starting enrichment. This detail is small, but very important. It is this that helps start a cold scooter engine without hemorrhoids in any weather. Only thanks to her, the scooter starts easily with half a kick, and for those who don’t, it means their hands are growing crookedly. Thanks to her, my dear, the scooter does not shoot into the muffler like domestic motorcycles, but idles quietly and smoothly. Thank the Japanese for inventing this thing! - I say in all seriousness.

So, what does it mean - launcher enrichment agent? This is essentially an additional small carburetor, standing parallel to the main one. It is connected to the main carburetor by three channels - air, emulsion and fuel, drilled in its body. The air is taken in before the throttle valve, the emulsion (mixture) is supplied after it, directly into the carburetor outlet pipe. Gasoline is taken from a common float chamber. Thus, with some stretch, the enrichment can be considered an independent device. It’s a stretch, because it is, nevertheless, structurally inseparable from the carburetor.

Now let's look at the drawing.

The carburetor has a small additional fuel chamber 7, which is connected to the main float chamber 8 through the start jet 9. The tube from chamber 7 leads to the mixing chamber into which air is supplied and from which the air-gasoline mixture goes into the engine. A valve 6 can move in the mixing chamber, similar to a carburetor throttle valve, only much smaller in size. Just like in the throttle, in launcher The damper contains a spring-loaded needle, which closes the fuel channel when the damper is lowered. When starting a cold engine, the damper is raised (open). At the first engine revolutions, a vacuum is created in the emulsion channel and gasoline located in chamber 7 is sucked into the engine, causing a strong enrichment of the mixture and facilitating the first flashes in the engine.

After the engine has started, but has not yet warmed up, it needs a rich mixture. The enricher works like a parallel carburetor; gasoline enters it through jet 9, mixes with air and enters the engine. When the engine is running, alternating current from its generator is always supplied to the contacts of the ceramic heater 2 of the thermoelectric valve of the starting system. The heater warms up the actuator 3. Inside it, obviously, there is a gas or liquid boiling at a low temperature and a piston connected to the rod 4. When the actuator is heated, the rod gradually extends by 3-4 mm and through the pusher 5 sets the damper in motion. Valve body 1 is wrapped in thermal insulation (polyethylene foam) and covered with a rubber boot.

Thus, the engine warms up along with the thermoelectric valve and the mixture gradually becomes leaner. After 3-5 minutes, the damper closes completely and the degree of enrichment of the mixture on a hot engine is set only by the carburetor idle system. When the engine stops, heating of the valve stops, the damper drive cools down and under the action of spring 10, pusher 5, rod 4 and damper 6 return to their original position, opening the channels for subsequent start-up. Cooling down and returning to its original position also occurs within a few minutes.

This enricher design is used on almost all modern scooters. Older models may use a design without an electric heater; heat is transferred to the drive through a copper heat-conducting cylinder directly from the engine cylinder. Sometimes, there is also a manual drive of the damper through a cable from the handle on the steering wheel (“Choke”).

Now the “diseases” of the system

1. The air channel may be clogged with dirt. In this case, the mixture becomes very rich, even after the engine has warmed up.

2. The jet may be clogged with dirt. It is very thin and this happens quite often. Wherein enrichment agent It works the other way around - it leans the mixture, making starting difficult.

3. Contact with the heater “tablet” is broken. The valve does not heat up and does not close. Engine It runs all the time on an over-enriched mixture and does not develop the required power. The resistance at the valve contacts is easy to measure; it should be in the region of several ohms.

4. The mustache is broken off

An integral part of every scooter is carburetor starter enricher or, as it is also called - scooter carburetor solenoid valve.

What is a starting enrichment

Start-up enricher (electrovalve)- this device is designed to supply an additional amount of air-fuel mixture into the combustion chamber during a cold start of the scooter engine. The fact is that when starting the scooter when it is cold, the engine requires an enriched mixture. The supply of such a mixture is ensured by carburetor solenoid valve. If the starting enrichment is in good working order and there are no breakdowns in other engine elements, the scooter engine starts easily even at temperatures around zero degrees.

Scooter starting enrichment device

There are two types of starting concentrators - manual and automatic.

Manual (mechanical) starting enrichment requires adjustment - it needs to be opened at startup and closed after the engine warms up using a cable on the steering wheel. But manually opening and closing the additional channel for supplying the mixture is inconvenient. Automatic starting enrichment (thermoelectric valve) is installed on most modern 2t and 4t scooters. We will learn about the device of the automatic starting enrichment further.

The scooter carburetor has a small additional fuel chamber 7, which is connected to the main float chamber 8 through the start nozzle 9. The tube from chamber 7 leads to the mixing chamber into which air is supplied and from which the air-gasoline mixture goes into the engine. A damper 6 can move in the mixing chamber, similar to carburetor throttle valve, only much smaller in size. Just like the throttle valve, the starting valve contains a spring-loaded needle that closes the fuel channel when the valve is lowered. Valve body 1 is wrapped in thermal insulation (polyethylene foam) and covered with a rubber boot. Such concentrator design used on almost all modern scooters.

Can be used on older models design without electric heater, heat is transferred to the drive through a copper heat-conducting cylinder directly from the scooter engine cylinder, and instead of powder with a heating element, a membrane. One cavity of the flask, where it is located, is connected through a thermal valve to the intake manifold, which is mounted on the cylinder head.

The principle of operation of the scooter carburetor solenoid valve

When engine is cold the valve with the spool needle 6 is raised as high as possible (open). The needle opens the fuel supply channel, and the flap opens the air supply hole. At the first revolutions of the engine, a vacuum is created in the emulsion channel and gasoline located in chamber 7 is sucked into the engine through channel A, causing strong mixture enrichment and easing the first flare-ups in the engine. After the engine has started, but has not yet warmed up, it still needs enriched mixture. The enricher works like a parallel carburetor - gasoline enters it through jet 9, mixes with air and enters the engine.

When the engine is running, alternating current from its generator is always supplied to the contacts of the ceramic heater 2 of the thermoelectric valve of the starting system. Heater 2 warms up drive 3. As warming up the engine and the drive, the rod gradually extends by 3 ... 4 mm and, through pusher 5, sets the damper in motion. Thus, The engine warms up along with the thermoelectric valve, the spool with the needle drops and closes the air and fuel channels, and the mixture gradually becomes leaner. After 3 ... 5 minutes, the damper closes completely and the degree of enrichment of the mixture on a hot engine is only regulated carburetor idle system.

When the engine stops valve heating stops, the damper drive cools down (the powder is compressed) and under the action of spring 10, pusher 5, rod 4 and damper 6 return to their original position, opening the channels for subsequent start-up. Cooling down and returning to its original position also occurs within a few minutes.

Disadvantage of the enrichment This type is that it functions separately from the engine. For example, very often, especially in warm weather, while the engine is still hot and there is no need to enrich the mixture, the thermoelement is already cooling down. We start the engine and it gets a rich mixture.

Operating principle of the second type of starting enrichment (with a membrane)

Cold valve is open. After starting the engine, a vacuum occurs in the manifold and through thermal valve supplied to the membrane. As a result of low pressure, the membrane rises and opens a channel for additional air supply. As the cylinder head warms up, the valve closes and the valve with the needle is lowered under the action of a spring, cutting off the additional fuel supply.

With this design principle, the connection with the actual engine temperature is maintained, and fuel dosage done more correctly.

Your carburetor may be equipped with a solenoid valve that prevents the engine from idling when the ignition is turned off, the solenoid valve is usually located on the outside of the carburetor. If your car does not start at all or is difficult to start, then the problem is likely in the carburetor solenoid valve, which needs to be adjusted.

Tools and materials:

• carburetor solenoid valve
• tachometer
• screwdrivers

Process:

1. Install the tachometer.
2. Turn on your car's engine and let it warm up.
3. Using the nut located at the end of the carburetor solenoid valve, you need to set a certain number of idle speeds (about 700 per minute).
4. Next, you must disconnect the wiring that comes from the carburetor solenoid valve, after which the speed will decrease.
5. Adjust the position of the throttle drive thrust screw by turning the screw with a screwdriver (clockwise - increase the speed, counterclockwise - decrease) until the tachometer needle stops at the desired value (see the operating instructions for your car).
6. If a lean screw is installed (instead of a throttle drive thrust screw), then the idle speed is adjusted as follows: by turning the lean screw clockwise you reduce the speed, and counterclockwise you increase it.
7. Finally, connect the wiring that comes from the carburetor solenoid valve.