9161F4-0625 Nissan BOLT

Illustration 1 g02057673
Fuel system schematic
(1) Cylinder head
(2) 550 kPa (80 psi) regulator
(3) Fuel rail pressure sensor
(4) Lines between the rail and the cylinder head
(5) Rail
(6) Pressure relief valve
(7) 600 kPa (86 psi) regulator for the high-pressure fuel pump
(8) High-pressure fuel pump
(9) Fuel transfer pump
(10) Fluid sampling valve
(11) Secondary fuel filter
(12) Backflow check valve
(13) Optional hand priming pump
(14) Fuel filter base
(15) Forward fuel manifold
(16) 1250 kPa (180 psi) pressure regulator
(17) 500 kPa (72 psi) pressure regulator
(18A) Fuel enable valve in the de-energized position
(18B) Fuel enable valve in the energized position
(19) Main fuel control solenoid
(20) Pilot fuel control solenoid
(21) Rear fuel manifold
(22) Pilot fuel pressure sensor
(23) Main fuel pressure sensor
(24) Primary fuel filter
(25) Fuel tankLow Pressure Fuel System - The low-pressure fuel system provides a fuel pressure of approximately 480 kPa (70 psi) to high-pressure fuel pump (8). The low-pressure fuel system provides a fuel pressure of approximately 1700 kPa (250 psi) at solenoids (19) and (20) for the ARD when the ARD is on.High Pressure Fuel System - The high-pressure fuel system provides fuel at high pressure for the injectors. The pressure depends on the engine operating conditions. The actual fuel pressure can be viewed on the Caterpillar Electronic Technician (ET).The vehicle fuel tank (25) provides fuel for cylinder head (1) and for the ARD. Primary fuel filter (24) is a 10 micron filter. All of the fuel for the cylinder head and for the ARD passes through the primary fuel filter. Fuel transfer pump (9) pressurizes the fuel.Fuel Enable Valve (18)This valve is controlled by the Engine Control Module (ECM). The valve has two positions. The following paragraphs describe each position.De-Energized Position (18A) - 1250 kPa (180 psi) regulator (16) is bypassed by a passage in the valve. Fuel cannot flow to solenoids (19) and (20). Regulator (17) establishes the fuel pressure at the inlet of fuel filter base (14) at approximately 500 kPa (72 psi).Energized Position (18B) - The 1250 kPa (180 psi) regulator (16) is now part of the system. The fuel transfer pump develops a fuel pressure of approximately 1700 kPa (250 psi). This pressure is regulated by 1250 kPa (180 psi) regulator 16 kPa and 500 kPa (72 psi) regulator (17). Fuel at this pressure is routed to solenoids (19) and (20) through a passage in valve (18). Fuel at approximately 500 kPa (72 psi) continues to be supplied to the inlet of the fuel filter base.Optional hand priming pump (13) provides a means for removing air from the system. Backflow check valve (12) prevents fuel from draining from the high-pressure fuel pump when the engine is not running. Secondary fuel filter (11) is a 2 micron filter. All of the fuel for the cylinder head passes through the secondary fuel filter. Fluid sampling valve (10) provides a port for taking fuel samples and for measuring fuel pressure.High-pressure fuel pump (8) creates high fuel pressure for the engine. Regulator (7) establishes an internal operating pressure of 600 kPa (86 psi) for the high-pressure fuel pump. Excess fuel flows through regulator (7) to the vehicle fuel tank.Fuel rail pressure sensor (3) sends a signal to the ECM. The signal indicates the fuel pressure inside rail (5). Pressure relief valve (6) relieves excess pressure in the rail, if necessary. Regulator (2) establishes a fuel pressure of approximately 550 kPa (80 psi) inside the cylinder head. The fuel injectors require this return pressure in order to operate correctly.Component Identification
Illustration 2 g03780031
Left side of the engine
Regulator (7) is behind pump (8).
(1) Cylinder head
(2) 550 kPa (80 psi) regulator
(3) Fuel rail pressure sensor
(4) Lines between the rail and the cylinder head
(5) Rail
(6) Pressure relief valve
(8) High-pressure fuel pump
(9) Fuel transfer pump
(10) Fluid sampling valve
(11) Secondary fuel filter
(12) Backflow check valve
(13) Optional hand priming pump
(14) Fuel filter base
(15) Forward fuel manifold
(16) 1250 kPa (180 psi) pressure regulator
(17) 500 kPa (72 psi) pressure regulator
(18) Fuel enable valve
(19) Main fuel control solenoid
(20) Pilot fuel control solenoid
(21) Rear fuel manifold
(22) Pilot fuel pressure sensor
(23) Main fuel pressure sensorLines and Ports
Illustration 3 g01444224
Configuration for C7 engines and C9 engines that are not installed in recreational vehicles
(26) Line from the outlet of the fuel filter base to the inlet of the high-pressure fuel pump
(27) Inlet to the high-pressure fuel pump
(28) Line from the outlet of the high-pressure fuel pump to the rail
(29) Port for pressurized oil for the high-pressure fuel pump
(30) Line from the forward manifold to the inlet of the fuel transfer pump
(31) This support provides a passage for return fuel from regulator (7) to vehicle fuel tank.
(32) Line for return fuel from regulator (7) to the vehicle fuel tank
(33) Line for return fuel from the cylinder head
(34) Line for return fuel from the rail
(35) Port for purge air to the ARD
(36) Ports for return fuel to the vehicle fuel tank
(37) Line from the forward fuel manifold to the inlet of the fuel filter base
(38) Fuel line from the primary fuel filter
(39) Line from the outlet of the fuel transfer pump to the forward fuel manifold
(40) Line for main fuel to the rear fuel manifold
(41) Line for pilot fuel to the rear fuel manifold
Illustration 4 g01444231
Configuration for C9 engines that are installed in recreational vehicles
(27) Inlet to the high-pressure fuel pump
(28) Line from the outlet of the high-pressure fuel pump to the rail
(29) Port for pressurized oil for the high-pressure fuel pump
(30) Line from the forward manifold to the inlet of the fuel transfer pump
(32) Line for return fuel from regulator (7) to the vehicle fuel tank
(33) Line for return fuel from the cylinder head
(34) Line for return fuel from the rail
(35) Port for purge air to the ARD
(36) Ports for return fuel to the vehicle fuel tank
(37) Line from the forward fuel manifold to the inlet of the fuel filter base
(39) Line from the outlet of the fuel transfer pump to the forward fuel manifold
(40) Line for main fuel to the rear fuel manifold
(41) Line for pilot fuel to the rear fuel manifold
(42) Line for fuel from the fuel transfer pump via the rear fuel