What is a Water Pressure Regulator?

The oil pressure regulator refers to adjusting the fuel pressure entering the injector according to the change of the vacuum degree of the intake manifold, so that the difference between the fuel pressure and the intake manifold pressure is kept constant, and the fuel injection pressure is opened at different throttles. A device that maintains a constant value under the temperature.

The oil pressure regulator is installed at one end of the fuel distribution pipe and has two functions: one is to adjust the fuel pressure of the fuel supply system so that the difference between the system oil pressure and the intake manifold pressure is kept constant (the set value is generally 300kPa) The second is to buffer the pressure pulsation generated by the fuel pump and the pressure fluctuations caused by the intermittent injection of the injector.

The oil pressure regulator is mainly composed of a spring, a valve body, a valve and an aluminum alloy housing. The valve body is fixed on the metal diaphragm, and a ball valve is installed between the valve body and the valve. The ball valve is supported by a spring sheet, and a small spring force is provided between the ball valve and the valve body, so that the ball valve and the valve are kept in contact. On the aluminum alloy housing, there are oil pipe joints and vacuum pipe joints. The oil inlet joint is connected to the fuel distribution pipe. The oil return joint is connected to the oil return pipe and communicates with the fuel tank. Vacuum tube connection. ^[1]

1) The oil pressure regulator is actually an over-flow relief valve controlled by a diaphragm. The diaphragm divides the regulator into an upper spring chamber and a lower fuel chamber. The opening of the overflow valve is controlled by the diaphragm to maintain the pressure balance between the upper and lower chambers.

2) When the oil pressure in the fuel chamber rises over the combined force of the spring pressure and the vacuum gas pressure, the diaphragm arches upward, the regulator valve opens, and some fuel flows from the ball valve to the fuel tank through the oil return port, which reduces the fuel pressure. When the pressure is reduced to the set pressure of the regulator, the ball valve is closed to maintain a certain pressure in the oil path from the oil pump check valve to the pressure regulator. ^[2]

1) When

Maintenance of oil pressure regulator includes oil pressure check of oil supply system, check of sealing performance and pressure holding ability.

In order to ensure that the fuel supply system can supply sufficient fuel under various operating conditions of the engine, the fuel pressure actually supplied by the fuel supply system is not a fixed value under different operating conditions. When the power supply voltage is normal, connect the oil pressure gauge to the fuel inlet of the fuel distribution pipe, start the engine and run at idle speed, the pressure rating of the oil pressure gauge should be (300 ± 20) kPa; when the throttle opening is suddenly increased The pressure of the oil pressure gauge should increase rapidly to about 320kPa; when the vacuum tube on the oil pressure regulator is removed, the pressure of the oil pressure gauge must rise to 320kPa. If the oil pressure does not meet the above requirements, it indicates that the oil supply system is faulty and should be repaired or replaced. The cause of excessive oil pressure is the damaged oil pressure regulator, which should be replaced with a new one. The cause of the low oil pressure is a leak in the oil pipe joint or oil pipe, a clogged fuel filter, a low battery voltage, or a damaged oil pressure regulator.

When the power supply voltage is normal, start the engine and run at idle speed, after the oil pressure gauge reaches the above rated value, turn off the ignition switch. After 10 minutes, the oil pressure gauge must be higher than 200kPa. If the pressure is lower than 200kPa, start the engine again and run at idle speed to make the pressure reach the rated value, then turn off the ignition switch, clamp the oil return pipe, and observe the oil pressure gauge. After 10 minutes, if the gauge pressure is higher than 200kPa, the oil pressure regulator has failed and should be replaced. If the gauge pressure is lower than 200kPa, it indicates that there is a leak in the fuel pipe or injector, or the check valve of the fuel pump is faulty, or the O-ring seal at the injector inlet is ineffective, and it needs to be repaired gradually. When the fuel injector is unplugged and checked for oil leakage, under normal oil pressure conditions, the oil dripping should not exceed 2 drops per minute. ^[1]