When Bare Engine are working, the working conditions of the crank-connecting rod mechanism are quite harsh, and they must withstand high temperature, high pressure, high speed and chemical corrosion. Therefore, the material and structure requirements of the crank-connecting rod mechanism are quite high.

The forces acting on the crank-connecting rod mechanism have gas pressure and mass inertia force of moving parts. The reciprocating inertia force and the rotational inertia force are transmitted to the Cummins Engine bracket through the main bearing and the body, which is the main source of vibration of Bare Engine.

Whether the Cummins Engine works smoothly and quietly has a lot to do with the balance of these forces. Because this aspect is done well, some high-end cars have very little vibration.

The body is the cylinder block, cylinder head and oil pan of the Cummins Engine, which is the support of the Cummins Engine and the assembly matrix of the crank-connecting rod mechanism, the valve mechanism and the main components of the Cummins Engine system.

The body is generally cast with high-strength gray cast iron or aluminum alloy. Nowadays, the application of aluminum alloy body in Bare Engine is becoming more and more common. The advantages of aluminum alloy cylinder body are light weight and good heat dissipation.