900 L4-1985cc 2.0L SOHC Turbo VIN S FI (1984)
Fuel Pressure Regulator: Description and Operation
Fig. 3 Fuel Pressure Regulator
The fuel pressure regulator, Fig. 3, ensures that the pressure in the fuel circuit remains constant when the fuel pump is in operation, by returning
excess fuel to the tank. When the fuel pump is turned off, the fuel pressure drops to approximately 36 psi (2.5 bar) and the regulator closes the port to
the return line and the rest pressure is maintained by means of of the "O"-ring seal and the fuel retained by the fuel accumulator. The purpose of this
rest, or residual, pressure is to prevent the fuel from vaporizing in the line when the engine is warm, making restarting difficult.
