Product Descreiption
1. Specifications
- Part Number: 3931379 (Cummins genuine part)
- Application: Cummins QSC8.3 / ISC8.3 diesel engines
- Type: External meshed gear (drive/driven set for oil pump)
- Material: High‑strength alloy steel, heat‑treated for wear resistance
- Weight: Approx. 7.8 lbs (3.5 kg)
- Dimensions (approx.): 10 in × 2.2 in × 9.9 in (254 mm × 56 mm × 251 mm)
- Gear Teeth: Standard QSC8.3 oil pump gear profile
- Operating Pressure: Up to ~40 psi (276 kPa) engine oil pressure
- Flow Rate: Matches QSC8.3 lubrication system demand (~25–30 gpm)
2. Installation Position
- Location: Inside the front gear housing, at the lower front of the engine block; mounted to the oil pump assembly, above the oil pan
- Drive: Driven by the crankshaft gear via the engine’s front gear train
- Mounting: Bolted to the oil pump housing (4 fasteners); the oil pump attaches to the engine block’s front gear case
- Orientation: Installed with gear meshing facing the crankshaft; “UP” marking on gear housing aligns with engine top
3. Function
- Core Role: Transfers rotational power from the crankshaft to the oil pump, driving it to circulate lubricating oil
- Lubrication Delivery: The oil pump draws oil from the oil pan, pressurizes it, and supplies it to:
- Crankshaft main bearings & connecting rod bearings
- Camshaft bearings & valve train components
- Piston cooling jets & cylinder walls
- Turbocharger bearings (if equipped)
- Pressure Regulation: Maintains stable oil pressure across varying engine speeds/loads, preventing pressure spikes or drops
- Wear & Heat Reduction: Ensures continuous oil film between moving parts, minimizing friction, wear, and heat buildup
- System Reliability: Robust gear design minimizes slippage, ensuring consistent oil flow and long service life in heavy‑duty applications (marine, industrial, etc.)
