Radiator Hose Replacement

What does the radiator hose do?

Hoses are designed to be flexible connections that carry coolant (antifreeze) between the engine and other temperature sensitive components on the car. Radiator hoses are the largest, most well-known. They attach the radiator to the engine. They route coolant to the radiator to be cooled and then return it back into the engine, so it can keep a certain temperature and run at peak efficiency. Heater hoses direct coolant into the car’s heating unit. Even smaller hoses bring coolant into other components, like a throttle body or pump, or intake, to keep them at efficient temperatures during the winter or summer extremes. All of these hoses, small and large, are made from rubber to add flexibility when the engine moves around.

When should you replace your radiator hose?

Even though automotive manufacturers do not provide any mileage intervals for radiator hose replacement, they should be changed periodically as part of an overall preventative maintenance plan. Some experts claim that hoses will last upwards of eight to ten years; others recommend every four to five years or 50,000 miles. Radiator hose life cycles really depends on proper coolant maintenance. If coolant is not flushed out of a vehicle regularly according to manufacturer guidelines, hose life cycles will shorten. Depleted coolant cannot prevent rust and corrosion, and electrochemical degradation eats at hoses and other coolant system parts.

What are the symptoms of a faulty radiator hose?

Any crackling sound when the radiator hose is squeezed under ambient temperatures (non-running) is a sign of degradation and the hose needs to be replaced. Seasonal extremes and high amounts of idling are also factors. Hoses are made from rubber, and over time, under the heat of the engine and the coolant passing through, they will harden and dry out. Lastly, long term contamination of the hose from leaking oil should be addressed with a new hose. Oil becomes acidic over time and will eat away at the rubber.

What can happen if the radiator hose is not replaced in a timely fashion?

If hoses are neglected, a series of problems may arise with the cooling and heating systems of the car, many which can lead to breakdown or failure of the engine. Most radiator hoses when they are old or hardened will begin to weep - slowly leak - coolant, particularly around the ends. Coolant loss will cause the engine to run hotter and inefficiently. Eventually, if this lost coolant is not replaced, the car will overheat to the point where the plastic parts start to melt and friction between moving metal parts overcomes oil lubrication. The engine will seize. Old hoses cannot hold pressure as well and as such are very prone to sudden failure.

You're in luck. This is one of the most inexpensive preventative repairs you can make. Also, most automotive service professionals can perform this service. Save time by using Openbay to compare pricing and book an appointment with a service center in your area.

Service article written by an ASE Master Technician