A radiator hose is very important in a cooling system. Without it, the radiator and coolant are both rendered useless since there will be no means to cool vital engine components. The radiator hose ensures that the coolant is distributed from the engine and back to the radiator. It also acts as the highway of the coolant through which heat flows back to the radiator where it is cooled. The coolant, a mixture of water with ethylene glycol is also called "antifreeze." It flows to the engine, where the heat is taken away, and back to the radiator. This happens when the coolant is cooled by the air coming through the grille or from the radiator fan.

Although they commonly come in the form of rubber, various types of radiator hoses are now available. There are the accordion hoses, molded hoses, and the ordinary radiator hoses. Even if the radiator hose is durably made, however, it is still prone to deterioration. As fuel combustion occurs, high pressure and high temperature gas are released, leading to the high possibility of overheating. This means that the cooling components are not functioning well.

To avoid severe damages to the radiator hose, experts advise to change it once every four years. Having it professionally assessed also proves to be helpful. However, inspecting and replacing the radiator hose can be done by any motorist. The procedure starts by running the hand along each hose. The hose must not be brittle, overly soft, or swollen. A replacement is needed when it has cracks and leaks. The first thing to do when replacing the radiator hose is to empty the radiator of existing coolant. Once all the coolant is gone, removing the defective radiator hose is next. Before placing the new radiator hose, its interior should be greased. The new hose then is ready for clamping, while the radiator has to be filled with new coolant.