The sequence diagram of the 4 piston rings, the installation video of the 4 piston rings

Piston rings are divided into two types: gas ring and oil ring. The gas ring is used to seal the compressed air in the combustion chamber, and the oil ring is used to scrape off excess oil on the cylinder. Some engines use four piston rings, three gas rings and one oil ring. What is the installation sequence of the four piston rings?

The installation sequence and orientation of the piston ring need to be paid attention to. The marked side is up, first install the bottom oil ring, then the third gas ring, the second gas ring, and finally the first gas ring. After the piston ring is installed, you also need to pay attention to the piston ring opening. The ring openings should be staggered to prevent the combustible mixture from leaking from the opening gap of the piston ring when the engine is started, which makes the engine difficult to start. The openings of the first and second piston rings are staggered by 180°, the openings of the second and third piston rings are staggered by 90°, and the openings of the third and fourth piston rings are staggered by 180°.

Four-way piston ring installation video

The piston ring is a precision part, and its shape is easy to change. Once deformed, it will cause light leakage. If the opening gap is artificially enlarged, it may cause oiling, air leakage, and pressure drop. Therefore, it should be stored flat to avoid unstable placement. Before installing the piston with the piston ring assembled into the cylinder, apply engine oil to the cylinder, piston, and piston ring first, then fully close the piston ring to the cylinder diameter, and install the piston into the cylinder.