Cummins
Main bearing shell for Cummins 6BTAA5.9-C178
This main bearing shell is designed for Cummins engines, including the 6BTAA5.9-C178, QSM11-C335, QSM19-C700, and KTA38C-1050 models. It features a .010 over-size specification for use with machined crankshafts.
Compatible models
Specifications
- Part number
- AR12271
- Brand
- Cummins
The main bearing shell AR12271 supports the engine crankshaft, facilitating smooth rotation while managing the loads generated by combustion and piston movement. This component is designed to maintain proper crankshaft alignment and distribute loads within the engine block. The .010 specification indicates an over-size measurement, which is necessary when a crankshaft has been machined to compensate for wear during an engine rebuild.
This component is compatible with several Cummins engine models, specifically the 6BTAA5.9-C178, KTA38C-1050, QSM11-C335, and QSM19-C700. These engines are frequently utilized in heavy construction machinery, industrial cranes, and mining equipment. Proper selection of this bearing is required to ensure the correct clearance between the crankshaft and the engine block, which is necessary for the formation of a hydrodynamic oil film during operation.
Main bearings serve as the interface between the rotating crankshaft and the stationary engine block. By providing a low-friction surface, they allow the crankshaft to spin freely under high pressure. Maintaining the correct oil clearance is necessary to prevent metal-to-metal contact, which can lead to overheating, loss of oil pressure, and potential engine failure.