There are two main types of cylinder heads, the Overhead Valve (OHV) and the Overhead Camshaft (OHC). OHC can be further divided into Single Overhead Camshaft (SOHC) and Dual Overhead Camshaft (DOHC). Cylinder heads contain valves, guides, seats, and valve springs. Proper maintenance and tuning of the engine are crucial to prevent wear on these components. When rebuilding a cylinder head, it's ideal to replace all valves, guides, seats, and springs, but depending on the engine's condition, some parts may be reused. The disassembly process involves using a valve spring compressor tool to remove the valves, locks, and springs. Inspection is done for wear and damage, and various specialized tools are used to measure valve clearances, valve guide diameter, and spring pressure. Refinishing and repairing the cylinder head components may require machine shop assistance. Valves may need to be refaced, guides replaced, and seats machined. After thorough cleaning and inspection, the assembly process involves lubricating and inserting valves into their original positions, installing springs, retainers, valve locks, and camshafts for the respective engine type.