|Products Name:||Engine Accessories Excavator Engine Parts Eletric Fuel Pump||OE NO.:||EP500-0|
|Car Make:||Excavator||Application:||For Excavator|
Excavator Engine Parts EP500-0,
12v Electric Diesel Fuel Pump,
Fuel Pump EP500-0
Engine Accessories Excavator Engine Parts Eletric Fuel Pump EP500-0
|Products name||Engine Accessories Excavator Engine Parts Eletric Fuel Pump|
Structural characteristics of fuel pump
The fuel pump is composed of an electric motor, a pressure limiter, and a check valve. The electric motor actually works in the fuel in the oil pump housing. The fuel can lubricate and cool the fuel motor. Because there is nothing in the housing that can be ignited, it generally does not produce anything. Danger; the check valve is installed at the oil outlet, and the pressure limiter is located on the pressure side of the oil pump housing with a passage leading to the oil inlet. The ZYB ignition booster fuel pump is suitable for conveying diesel, heavy oil, residual oil, fuel oil and other media, especially suitable for the fuel pump of the burner in the pump of the road and bridge engineering mixing station. It is an ideal product to replace imported products; similar to ammonia, Liquids with high volatility or low flash point, such as benzene, are not suitable for transportation.
Common faults and troubleshooting of fuel pumps
(1) The fuel pump does not rotate
If the electric fuel pump does not work, it means that the fuel pump or the circuit is faulty, and you can check it according to the following steps:
a. Check whether the power plug of the fuel pump is loose and whether the connecting wire is disconnected. The method is: unplug the fuel pump plug, connect the test light to the two terminals of the plug, turn on the wire switch, if the test light is on, it means that the power supply voltage is normal, and the fuel pump is faulty; if the test light is off, it means the circuit If there is a fault, it should be searched according to the circuit diagram. 
b. Check the fuse, main relay, power-off relay and their connections. You can turn off the ignition switch, open the fuse box cover on the left side of the dashboard, pull out the fuse of the fuel pump, and connect the wire with a switch to both ends of the fuse holder. The other end of the wire is connected to the positive electrode of the battery, and the wire switch is turned on , Check if you can hear the sound of the fuel pump running. If the fuel pump still does not rotate, it means that the fuse or relay is open.
c. If it is normal after the above inspection, but the fuel pump still does not rotate, it may be a problem with the fuel pump switch. In the L-type electronically controlled fuel injection system, the fuel pump switch is located in the air flow meter. In addition to being controlled by the ignition switch, the electric fuel pump is also controlled by the air flow meter. Only when the engine is started and there is air flow in the air flow meter When the electric fuel pump can work. Therefore, when checking the fuel pump of the L-type electronically controlled fuel injection system, the fuel pump check switch in the control circuit should be pressed. 
2. The fuel pump can rotate but does not deliver oil
The main reasons why the fuel pump can rotate but not deliver oil are:
a. The fuel inlet filter of the fuel pump is blocked. Take out the fuel pump from the fuel tank and check it. It can be seen that the three filter screens of the fuel pump are almost blocked by black powdery impurities. Put it in gasoline to clean it, and then use compressed air to blow off the filter and oil passages, and then troubleshoot.
b. The fuel pump check valve is stuck in the closed position, the fuel inlet is blocked, and the pumped fuel cannot enter the fuel delivery pipe.
c. The spring of the pressure relief valve (or safety valve) is broken, the valve is stuck in the open position, and the pumped fuel flows back to the fuel tank through the pressure relief valve (or safety valve).
d. The fuel pump impeller and pump casing are severely worn. In this case, only replace the fuel pump. 
3. The pump oil pressure is too low
If the oil pressure is too low, the fuel injection volume of the injector will be reduced, resulting in difficulty in starting the engine and a decrease in power. The judgment method is: connect an oil pressure gauge to the oil circuit to stabilize the engine speed at 3 000 r/min. If the pointer of the oil pressure gauge swings rapidly between 220 and 300 kPa, it indicates that the fuel pump pressure is normal; The pointer of the pressure gauge stops slightly at a certain position, indicating that the fuel pump has worn out. You can also use the pressure gauge to test the fuel supply pressure of the fuel pump by squeezing the fuel return hose of the fuel pressure regulator with your hands. If the fuel pressure is still too low at this time, it means that the fuel pump is not supplying enough. The fuel pump should be replaced if the pressure relief valve (or safety valve) leaks, the fuel inlet filter is blocked, the impeller and the pump casing are worn, etc.; if the fuel pressure can rise to more than 300 kPa after pinching the return pipe, it means that it is not a fault of the fuel pump , The fuel pressure regulator should be checked for damage.
Contact Person: Keith