Sinotruk Fuel Supply System

1. Composition of fuel supply system

The composition of the fuel supply system: fuel tank, fuel pipe, fuel pump, HOWO fuel filter, HOWO air filter, fuel pressure regulator, fuel injector, cold start injector, oil pressure pulse attenuator, intake pipe, exhaust pipe wait.

2. Working principle of fuel supply system

1) Fuel tank (gasoline tank) – used to store fuel.

2) Fuel pump (electric gasoline pump) —- its function is to pump fuel from the fuel tank into the fuel pipeline, and keep the fuel at a certain pressure, and deliver it to the fuel injector and cold start valve through the filter . The fuel pump is divided into two types according to its installation position: external pump and internal pump.

The external pump is to install the pump in the fuel pipeline outside the fuel tank, and the internal pump is to install the pump in the fuel tank. Compared with external pumps, it is not easy to produce air resistance and fuel leakage, and has low noise. Most use built-in pumps.

3) Fuel buffer – also called pulsation damper. Its function is to stabilize the oil pressure pumped by the fuel pump, reduce pressure fluctuations and reduce noise.

4) Fuel pressure regulator—A pressure regulator is installed in the oil circuit, which keeps the fuel pressure constant relative to the air pressure or the negative pressure of the intake pipe, that is, keeps the difference between the fuel injection pressure and the fuel injection environment pressure constant.

The pressure difference is generally maintained at 250kPa. When the oil supply pressure exceeds the specified value, the pressure reducing valve in the pressure regulator opens, and the gasoline flows back to the fuel tank through the oil return pipe, so that the oil pressure of the oil delivery pipe remains constant.

5) Fuel filter—Installed in the oil circuit between the fuel buffer and the injector, its function is to filter out the water and impurities in the fuel to prevent the fuel injector valve from being blocked.

6) Fuel injector—The fuel injector is installed at the air inlet of the throttle body (SPI system) or the intake manifold near the intake valve of each cylinder (MPI system), and is controlled by the fuel injection signal of the electronic controller. The amount of fuel injected is determined by the power-on time of the fuel injector, so that an appropriate amount of fuel is sprayed into the intake manifold in the form of mist.

The fuel injection principle of the fuel injector is: the fuel injection current signal is sent by the electric controller, and the current flows through the electromagnetic coil to generate electromagnetic suction force, which attracts the iron core. Injector blows out.

7) The thermostat timer switch and the cold start valve (cold start injector) The function of the thermostat timer switch is to monitor the temperature of the cooling water. When the engine starts and the temperature of the cooling water is 114C lower, the contact of the switch is closed to make the cold start Valve injection.

The function of the cold start valve is to inject extra fuel into the intake manifold when the engine is started cold, so as to improve the low temperature starting performance. Many cars have canceled the thermostat timing switch, and the work of the cold start injector is completely controlled by the ECU, and the control accuracy is higher.

3. Fuel supply system maintenance tips

Maintenance and repair of truck fueling systems play a vital role in ensuring their efficiency, reliability and longevity.

(1) Regular maintenance to detect and correct any potential problems with the fuel system, such as clogged or leaking fuel filters, which can affect engine performance.

(2) It is also important to use high-quality fuel and filters to prevent contamination and ensure optimal engine operation. In the event of a breakdown or malfunction, promptly repair or replace damaged parts (including injectors and pumps)

(3) It is recommended to arrange regular inspection and maintenance by experienced technicians and authorized service centers. This ensures the use of original quality parts and the best service standards.

In summary, proper maintenance and timely repair of the fuel supply system of Sinotruk trucks is essential to maintain their performance and reliability. Following recommended maintenance practices and using genuine parts can increase vehicle efficiency, reduce downtime and maximize overall profitability.

Related Posts