Process characteristics:In-line, four-cylinder, with dry cylinder liner. The core wall thickness of the water jacket of the cylinder block is relatively thin (4mm locally), and the sand core is easy to deform, which is easy to cause instability of the wall thickness of the cylinder hole. In the casting process, the water jacket core is equipped with parallel core heads at the cylinder top to enhance rigidity. In addition, the integral core assembling process is adopted, that is, the water jacket core and tappet core are assembled on the main core assembly before dip-coating, followed by integral dip-coating, to ensure the position accuracy of the sand core, so as to ensure the wall thickness of the cylinder hole.