BEARING-CAGED 5M2055 - Caterpillar

System Operation Description:The fuel system provides the engine and the Aftertreatment Regeneration Device (ARD) with pressurized fuel. This procedure verifies that the fuel system is working correctly. This procedure also troubleshoots the following diagnostic trouble codes:
157-17 Engine Injector Metering Rail 1 Pressure : Low - Least Severe (1)
1239-0 Engine Fuel Leakage : High - Most Severe (3)The fuel system has a low-pressure side and a high-pressure side. Refer to Illustration 1.
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