Learn More About Cummins Diesel Engine Pre-Lubrication System

In the fields of heavy machinery, mining equipment, and backup power generation, Cummins diesel engine series such as QST30, QSK19, QSK38, QSK45, QSK50, and QSK60 are highly favored for their outstanding performance. The pre-lubrication oil pump, as the core component of their lubrication system, is crucial for ensuring engine longevity and minimizing wear! Today, Dingbo Power delves into the working principles and key usage points of Cummins pre-lubrication oil pumps, helping you maintain equipment scientifically and extend engine life!

Pre-Lubrication Oil Pump: The Lubrication Guardian Before Startup

The Cummins pre-lubrication system employs either periodic automatic lubrication or remote design to ensure a stable oil film forms instantly upon engine start-up, preventing wear caused by dry friction. Its core principles are:

1. Working Principle

Pre-lubrication Before Startup: An electric oil pump draws oil from the oil pan and delivers it through a check valve to the main oil gallery and friction surfaces, ensuring oil pressure reaches the required level rapidly upon startup (e.g., above 28 kPa for QSK series).

Post-Shutdown Protection: When the engine shuts down (speed drops to 90 rpm), the pre-lubrication pump automatically activates, continuously supplying oil to cool bearings and prevent high-temperature carbon buildup.

Gear Pump Structure: The driving and driven gears mesh to create a pressure differential, efficiently sucking in and discharging oil. Pressure is regulated by a pressure relief valve to prevent damage from overpressure.

2. System Classification

Integrated Type: Integrated with the starter motor. Suitable for space-constrained models like QSK19 and QST30. Directly replaces the traditional starter, shortening pre-lubrication time.

Remote Type: Independently mounted on the engine bracket and connected to the oil pan via hoses. Suitable for heavy-duty models like QSK45 and QSK60, offering flexible adaptation to complex operating conditions.

Usage Precautions: Details Determine Lifespan

Installation Specifications

The solenoid valve must be installed horizontally and perpendicular (90°) to the crankshaft centerline to prevent vibration-induced false triggering. Keep it away from high-temperature exhaust components to prevent premature aging.

Suction hose length should not exceed 1.5 meters, secured with reinforced clamps to prevent vibration wear. Install a check valve in the discharge line to prevent oil backflow.

Oil Selection & Maintenance

Use Multi-Grade Lubricants: E.g., SAE 15W-40, balancing low-temperature fluidity and high-temperature viscosity to reduce cold-start wear (recommended ambient temperatures see table below).

Regularly Check Oil Pressure: Normal pre-lubrication pressure is 0.5 - 1.5 bar. If below 0.5 bar, investigate potential causes like pressure relief valve sticking or filter blockage.

Cleaning & Oil Change: Replace the oil filter every 500 hours to prevent metal debris from clogging lines. Poor-quality fuel accelerates pump wear; always use fuel meeting required specifications.

Fault Response

Low Pressure Alarm: Often caused by minor wear on the pressure relief valve or spring failure. Promptly replace with an improved valve core design (featuring enhanced reseating reliability without plug-in structures).

Winter Startup: NEVER use open flames to heat the oil pan! Use preheating devices to warm the coolant above 60°C and select low-pour-point oil (e.g., 5W series for -30°C environments).

The Cummins pre-lubrication system utilizes Holset turbocharging technology and precise electronic control module regulation, supporting rapid 15-second startup under load, meeting the demands of critical scenarios like data centers. Furthermore, authorized service providers offer genuine spare parts and professional maintenance services, ensuring system efficiency and uninterrupted power for your equipment!

Cummins has six engine joint ventures in China. Dongfeng Cummins produces B, C, and L series diesel engines, while Chongqing Cummins produces M, N, and K series diesel engines. Dingbo Power series Cummins generator sets are officially authorized products of Cummins Inc. They offer superior performance, better quality, and more reliable service guarantees compared to similar products.

Dingbo Cummins generator sets are suitable for industries such as real estate, schools, factories, hospitals, and outdoor operations. Their advantages—compact structure, ample power reserve, stable operation, excellent governing performance, low fuel consumption, reduced emissions, and low noise—meet the diverse power requirements across these industries.