The TOPRAN brand Radiator Hose is the part of the vehicle cooling system that conducts the coolant from the engine to the radiator and back. The heated coolant enters the radiator via the upper cooling water hose and the lower radiator hose is used to convey the cooled medium. The hoses are exposed to high temperatures, aggressive substances, vibrations and pressure and must therefore meet numerous requirements. They have to be tear-resistant, flexible and heat-resistant. They need a high resistance to ozone, engine vibrations and decomposition from the coolant. In fact, a car has several such cooling hoses. The number, shape and length of the radiator hose depend on the design of the engine.

1. 3 Coupe (E92)
2. 3 (E90)
3. 3 Saloon (E90)
4. 3 Touring (E91)
5. 3 Convertible (E93)
6. 1 Coupe (E82)
7. 1 Convertible (E88)
8. Z4 Roadster (E89)
9. See more in applications

The construction of the radiator hose

To connect car radiators to the engine water jacket, two branch pipes are used - inlet and outlet. They have their own design features.

The inlet pipe supplies hot coolant from the thermostat housing to the upper radiator tank. In most truck models, the top pipe consists of only one flexible sleeve that fits over the corresponding radiator and thermostat outlets, secured with metal clips.