## Head in Car Engine
The head of an engine is the uppermost part of the engine block, and it houses the valves, camshaft(s), and other components that control the flow of air and fuel into and out of the cylinders. The head is usually made of cast iron or aluminum, and it is bolted to the engine block.
### Functions of the Head
The head performs several important functions in the engine:
– It provides a seal between the cylinders and the outside of the engine.
– It supports the valves and camshaft(s).
– It provides passages for the flow of air and fuel into and out of the cylinders.
– It contains the combustion chambers, where the air and fuel are mixed and burned.
### Types of Heads
There are two main types of heads: overhead valve (OHV) heads and overhead camshaft (OHC) heads. OHV heads have the valves located in the block, while OHC heads have the valves located in the head itself. OHC heads are more efficient than OHV heads, but they are also more complex and expensive to manufacture.
### Components of the Head
The head is made up of several components, including:
– The valve seats are the surfaces in the head where the valves make contact.
– The valve guides are the passages in the head that guide the valves.
– The camshaft(s) are the shafts that control the opening and closing of the valves.
– The rocker arms (OHV engines only) are the levers that transfer the motion of the camshaft to the valves.
– The pushrods (OHV engines only) are the rods that connect the rocker arms to the camshaft.
– The intake and exhaust ports are the passages in the head that allow air and fuel to enter and exit the cylinders.
– The combustion chambers are the spaces in the head where the air and fuel are mixed and burned.
### Head Gaskets
The head gasket is a thin metal gasket that is located between the head and the engine block. The head gasket seals the combustion chambers and prevents coolant and oil from leaking out of the engine. Head gaskets can fail over time, which can lead to a loss of compression and power.
### Head Replacement
In some cases, it may be necessary to replace the head on an engine. This is a major repair that requires the removal of the head from the engine block. The head must be replaced with a new or rebuilt head, and the head gasket must be replaced as well.
### Conclusion
The head is an important part of an engine, and it performs several important functions. The head is made up of several components, including the valves, camshaft(s), and intake and exhaust ports. The head gasket seals the combustion chambers and prevents coolant and oil from leaking out of the engine. In some cases, it may be necessary to replace the head on an engine.
