GM Locomotive Lube Oil System Overview

GM Locomotive Lube Oil System

• The lube oil system is a combination of four separate systems: scavenging, soak-back, main lubricating, and piston cooling.
• Each system has its own oil pump.
• The main lubricating oil pump and piston cooling oil pump share the same housing.
• The scavenging and soak back pumps are separate.

Pump Discharges

• Main: 867 LPM (7-8 kg at 8th notch)
• Piston Cooling: 413 LPM (5-6 kg at 8th notch)
• Scavenging: 1703 LPM
• Soak Back: 11 LPM

Engine Assembly

• Engine model: RR-520
• Capacity: 14571ts
• Dip stick: per division 25Lts (right and left)
• Idle
• Lube oil strainer (Aux. Room, right side, engine)
• Shutdown

System Components

• The presentation includes diagrams of the various components (scavenging oil pump, oil filters, oil cooler, bypass valve, main lube oil pump) and their functions.
• The scavenging oil pump extracts oil from the oil sump, filters it, and then sends it through a cooler before sending it to the main lubricating oil pump or the piston cooling oil pump.
• There are two mesh strainers for the main lube pump oil. Each consists of a pleated, perforated metal core covered with mesh screening enclosed in a metal cylinder.
• The system has a pressure relief valve set at 32 psi in the soak back filter assembly that opens when the pressure from the motor-driven soak back pump is lower than the engine-driven pump.
• There is a bypass valve, set at 70 psi, located in the filter head and opens to bypass a plugged soak back filter element so lubrication can continue to the turbocharger allowing turbo damage to be prevented.
• A Crank - Case Pressure Shutdown switch will shutdown the engine when the pressure inside reaches a particular value.
• The Low Lube Oil switch attached to the Governor operates to shutdown the engine when the lube oil pressure drops to a particular value.
• A Hot Oil Detector shuts down the engine when the oil temperature reaches 126°C.

Trouble Shooting

• If the system is experiencing low oil pressure, the following steps should be taken:
  • Check the lube oil level. Add oil if needed.
  • Verify the oil viscosity.
  • Record the oil and water temperatures.
  • Clean the strainer housing.
  • Check for any suction leaks.
  • Replace the turbocharger oil filter element.
  • Remove crankcase covers, inspect piston pin, and connecting rod for any signs of overheating or loose components.