The pressure reducing valve is a container divided by a diaphragm, on which a valve is fixed, which closes the fuel drain hole under the action of a spring
The pressure reducing valve maintains a constant pressure in the supply system of about 0.3 MPa
The upper part of the pressure reducing valve is connected to the receiver by a vacuum hose.
When the pressure drop in the receiver is not higher than 0.3 MPa, the valve is closed and the pressure in the supply system rises.
When the fuel pressure reaches more than 0.3 MPa, the membrane flexes, opening the hole, and excess fuel is drained into the fuel tank.
As soon as the fuel pressure drops to 0.3 MPa, the membrane returns to its original position and closes the fuel drain hole.
Reduce the pressure in the fuel system if the engine has just been stopped.
Disconnect the wire from the "negative" terminal of the battery.
Remove the engine fuel line.
Disconnect fuel drain hose 1 and vacuum hose 4 from pressure reducing valve 3.
Remove two fastening bolts 2 and remove the pressure reducing valve 3 from the engine fuel line.
Install the new valve in reverse order.