What surrounds the parts of the engine that reach the highest temperatures?

The area surrounding the parts of the engine that reach the highest temperatures is known as water jackets. Water jackets are channels within the engine block that contain coolant. This coolant helps to absorb heat from the engine components, maintaining optimal operating temperatures and preventing overheating. By circulating the coolant through the jackets, heat is transferred away from critical engine parts, ensuring they do not exceed safe temperature limits.

While oil reservoirs play a role in lubricating engine components, they do not directly surround the hottest areas of the engine. Fuel injectors are responsible for delivering fuel into the combustion chamber but are not designed to manage heat. The exhaust manifold collects exhaust gases from the engine; while it does reach high temperatures due to the combustion process, it is not structured in a way that surrounds other high-temperature parts comprehensively in the same way that water jackets surround critical components.