Overhaul and maintenance of automobile engine This paper first introduces the disassembly and installation methods of engine cooling and lubrication system, which are often problems in engine cooling system through words and pictures. Then, the disassembly and adjustment of automobile engine parts, the actual operation steps inside the parts and the main factors leading to automobile engine failures are introduced in detail. The overhaul and maintenance of automobile engines are of great significance. Practical maintenance measures are put forward for common failures, and how to maintain the engine is introduced in the conclusion and prospect. It provides a solid theoretical basis for engine overhaul and maintenance, and is of great significance to the maintenance of automobile engines. Keywords: automobile engine; Cooling and lubrication system; Engine overhaul: lubrication system maintenance: lubrication protection performance