Electrovalves of gas equipment on a car. Setting up the pressure switch


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 assembly.

  • 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.

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.

Gas equipment for cars, abbreviated as LPG, is the latest, affordable and effective means of saving car fuel, increasing engine life and reducing the amount of harmful substances released into the environment - all in one bottle. Every year, the unfavorable situation in the oil price market and the general deterioration in the quality of gasoline cause a steady desire of car owners to switch to more economical and engine-friendly operating principles. The ability to refuel with liquefied propane and petroleum gas (methane) has been known since the mid-19th century; it appeared simultaneously with gasoline and diesel internal combustion engines and developed in parallel. But only from the late 70s of the XX century, gas equipment became truly in demand, and a developed infrastructure of gas stations and car service stations appeared.

In general, it includes a gas cylinder from which a gas line extends and at the end closes a multi-valve. Behind it, a geared evaporator converts the gas into working condition and accumulates it in portions in the manifold and injects it into the engine through separate injectors. The process is controlled by a control unit connected to the on-board computer (in more advanced models).

Classification

Today, a huge number of specialized manufacturers offer a wide range of gas equipment for both carburetor and injection types of engines of any complexity and configuration. Conventionally, all systems are divided into generations, each of which has its own operation and degree of automation of adjustment:

  • The first generation is the vacuum principle of dosing each gas portion. A special mechanical valve reacts to the vacuum that occurs in the car's inlet manifold when the engine is running and opens the way for gas. A primitive device for simple carburetor systems does not have any feedback from the engine electronics, fine adjustment and other optional add-ons.


  • Second-generation gearboxes are already equipped with the simplest electronic brains, which, by communicating with the internal oxygen sensor, act on a simple solenoid valve. This operating principle allows the car to not only drive as fast as it can, but also regulates the composition of the gas-air mixture, striving for optimal parameters. A practical and still widespread device among owners of carburetor cars, but in Europe it has already been banned for use since 1996 for its high level of environmental pollution.
  • The demand for representatives of the transitional third generation is quite low. These high-tech systems rely on autonomous software that creates its own fuel maps. Gas is supplied by a special built-in injector to each cylinder separately. The internal software emulates the operation of gasoline injectors using its own hardware capabilities. The design turned out to be not very successful; the weak processor of the unit froze, causing failures in the functioning of the mechanism. The idea was lost when a newer and more developed class of gas equipment appeared.


  • The most common gearboxes today are those with split injection of the gas-air mixture. This is a completed 3rd generation project, but uses standard petrol maps of the car in the configuration program, which does not burden the computing power of the control unit. There is a separate line of generation 4+, developed for direct-flow direct fuel injection systems directly into the FSI engine.
  • The newest product being introduced into the auto market is the 5th generation. The key feature of the operating principle is that the gas does not evaporate in the gearbox, but is pumped as liquid directly into the cylinders. Otherwise, this is full compliance with the 4th generation: split injection, use of data from the factory fuel map, automatic switching mode from gas to gasoline, etc. Another advantage that can be noted is that the equipment is fully compatible with current environmental standards and the latest on-board diagnostics .

Solenoid multivalve

In all these HBO systems, regardless of the class and principle of operation, a device such as a multivalve plays a key role. It is he who allows and blocks gas, filters the composition of the mixture, selecting harmful substances and impurities (which is why the built-in filter needs to be replaced regularly).


Initially, a conventional mechanical valve had only a shut-off function and was tightly welded directly to the cylinder. The first generation of vacuum-type equipment begins to use a valve with an additional vacuum membrane, which plays the role of a vacuum level sensor in the manifold. Further complexity of the design and general unification of cylinder necks from various manufacturers led to an increase in the number of simultaneously performed work operations. A modern electromagnetic multivalve for a car consists of a whole set of built-in valves connected by sensor feedback to an electronic control unit.

Functions of devices integrated into multivalves

  • Protects the cylinder from gas leakage

When the cylinder is filled to 80% with liquefied gas, the filling valve shuts off the fuel supply. Complete filling of the actual volume of the cylinder is unacceptable according to safety requirements - under the influence of some external factors, for example, a sharp change in the temperature of the environment, the gas can expand sharply, which can be fraught with dangerous consequences when fully loaded (the container can even explode), that is, when the pressure reaches at 25 atmospheres (standard storage device)


  • Adjusting the supply level to the gas main

There is a special anti-slam high-speed valve on the gas pipeline that regulates the rate of fuel supply into the gas pipeline. Additionally, it performs another safety function - it prevents potential leakage if deformation or breakage of the car line occurs.

Emergency fire protection for a car that runs on gas consists of a separate element of the multi-valve: the fuse will release fuel through the ventilation unit outside the car if a sharp and strong increase in temperature (hence, excess pressure in the system) signals the outbreak of a fire in the immediate vicinity of the LPG .

The presence of a fuse automatically transfers the safety category from class B to class A. It is strictly prohibited to install a gas multivalve without such a fuse on a cylinder with a capacity of more than 50 liters.


  • Measuring valve

To indicate the amount of gas remaining in the system, another separate filling valve is used, the operation of which is associated with a corresponding magnetic sensor. In injection systems of 3 or more generations, at the moment of automatic switching to gasoline if there is a shortage of alternative fuel, it is the gas measuring valve that closes the line.

  • Check valve

The second filling fuse operates only on gas inlet and prevents it from returning back during refueling.

  • Backup shut-off valves

Safety comes first: no matter how modern and computerized the equipment is, failures, malfunctions, and emergency situations are always possible. In a situation that requires decisive action from the driver of the car, two manual valves can be useful, which, if absolutely necessary, are always capable of forcibly shutting off the gas flow in the line.

Filtration properties of a multivalve

The standard design of HBO involves placing a multi-valve in a ventilation unit, which is located directly on the cylinder in a separate removable container. Special hoses go out to separate impurities and, in case of any danger, release the gas away from the car interior.


It is recommended to replace the air filter equipped with the ventilation box every 15-20 thousand kilometers to avoid severe clogging.

Manufacturers

The electromagnetic multivalve, along with the gearbox and control unit, is the most important component of gas equipment, on which the safe operation of the car depends, so choosing it should be taken as seriously as possible. All major gas equipment manufacturers also offer a multivalve in their range, suitable for different generations and shapes of the gas cylinder, as evidenced by the Cil (cylindrical) or Tor (toroidal) markings on the body. Italian brands are considered the highest quality, of which BRC, Tomasetto, Lovato, Atiker can be noted.


2023 kubanteplo.ru.