When the Bare Engine is working, due to the swing and large force, the rod will bend and twist, the ellipse and cone will wear the inner holes of the large and small ends, and the Isuzu Engine bolts will be damaged.

Bending or twisting of the Bare Engine will cause the piston to be skewed in the cylinder, resulting in wear between the piston and the cylinder and the connecting rod bearing, and air and oil leakage between the piston group and the cylinder. Therefore, the Bare Engine must be carefully inspected and corrected.

The axes of the large and small end bearing holes of the Isuzu Engine should be in the same plane, and the straightness of the Bare Engine and the twisting of the connecting rod should not be greater than 0.05 mm of the length of 100 mm.

Bending of the Bare Engine usually occurs in the plane formed by the axes of the large and small ends (front and back bending). After the Bare Engine is bent, the axes of the large and small end bearing holes of the Bare Engine are not parallel.

Twisting of the Bare Engine will cause the axes of the large and small ends to be not in the same plane. The center distance error of the large and small ends of the Bare Engine is generally 70.05 mm. The bending and twisting inspection of the Bare Engine is usually carried out on the Bare Engine inspector.