The water hose under the Citroen 15CV is a crucial component that regulates the flow of coolant in the engine bay. This hose plays a vital role in the cooling process, ensuring the engine runs at an optimal temperature. Made from durable, heat-resistant materials, the water hose prevents overheating and aids in extending the vehicle's lifespan. Regular inspection and maintenance of this hose are necessary to prevent leaks and engine troubles. Proper fitting and installation are essential for effective operation within the cooling system of the Citroen 15CV.