What is the function of an engine cylinder head?

[Fitzgerald]

The function of an engine cylinder head is: 1. To seal the upper part of the cylinder and form the combustion chamber; 2. To serve as a support for the camshaft, rocker arm shaft, and intake/exhaust pipes; 3. To draw air into the cylinder interior, where the spark plug ignites the combustible gas mixture, driving the piston to perform work and expelling exhaust gases through the exhaust pipe. There are two common types of engine cylinder heads: 1. The side-valve engine cylinder head, which is cast with a water jacket, water inlet hole, water outlet hole, spark plug hole, bolt hole, and combustion chamber; 2. The overhead-valve engine cylinder head, which, in addition to the cooling water jacket, includes the valve mechanism, intake and exhaust passages. A common issue is improper valve clearance (too large or too small), leading to valve noise or failure of the camshaft position sensor on the cylinder head.