How many microns of cylinder head deformation is normal?

[DelEvangeline]

No more than 0.50MM. If the cylinder head has already deformed or the accumulated grinding wear exceeds 0.50MM, it is recommended to replace the cylinder head with a new one. 1. Cylinder head: The cylinder head is installed on top of the cylinder block, sealing the cylinder from the upper part and forming the combustion chamber. It is frequently in contact with high-temperature and high-pressure gas, thus bearing significant thermal and mechanical loads. The cylinder head of a water-cooled engine has a cooling water jacket inside, and the cooling water holes on the lower end face of the cylinder head are connected to the cooling water holes of the cylinder block. Circulating water is used to cool high-temperature parts such as the combustion chamber. 2. Repair method: Since there is no concave combustion chamber on the engine cover, there is no need to consider changes in combustion volume (the change in combustion chamber volume should generally not exceed 4% of the original volume). The cylinder head surface is machined using a planing method. Instead of the rubber sealing ring on the cylinder gasket, the cylinder gasket is installed, and the cylinder head bolts are tightened using a method of cold tightening followed by hot tightening.