Coolant hoses can certainly wear out in the life span of your vehicle -- in fact, consumers reported in a national survey that two to three times as many radiator hoses failed while driving in their vehicle's fifth year than its fourth. 

The average four-year-old car has been driven nearly 70,000 miles, a mileage interval that most technicians believe is the time many parts wear out. Coolant hoses are no exception and the age of the car is a good indicator of when replacement should be considered.

Visually inspecting the hoses from the outside isn't always the best method since hoses usually fail from the inside where weakened elements can't be seen and their symptoms not always obvious.

For safety, the best recommendation is to replace the coolant hoses, especially the radiator hoses, every four to five years, regardless of physical appearance.

Use of dissimilar metals in today’s engines and coolant, which is also conductive, can create a sort of battery with the hose conducting electricity through itself. The electrical current can create tiny cracks in the hose tube, which eventually weaken and cause the hose to fail. This phenomenon is called electro-chemical degradation or ECD.

The higher operating temperatures in cramped engine compartments result in hotter temperatures for hoses. While increased temperatures result in greater engine efficiency, heat also increases the rate of ECD in hoses! In fact, for every 18-degree increase in temperature, the rate of ECD doubles.

Vibration from rough idling engines weakens other types of hose reinforcements -- again leading to premature failure. Also, abrasion from sharp surfaces within the engine compartment can slowly rub through the outer cover of the hose, eventually causing it to burst. Cuts and nicks on the outside of the hose also contribute to premature failure, but oil is a more common threat. A hose exposed to oil will be prematurely weakened since the oil actually attacks the rubber compound on the hose cover. Any of these signs indicate a hose that could fail at anytime.

There may be some reluctance to replace a coolant hose that hasn't presented any problems, but there are three benefits to doing so:

• Eliminate inconvenience. A hose on the verge of failure never bursts in the driveway or in the shop -- it bursts on the road, whether on a busy city street or a lonely country highway -- and the cost of a tow usually exceeds the cost of a hose.
• Avoid serious, more expensive damage. Older cast iron engines could take overheating better than today's mostly aluminum engines. An overheated engine can damage other expensive-to-replace components.

 

 

 

 

Wayne's Garage
Serving Eugene, Oregon and Springfield, Oregon's car, truck and SUV auto repair needs since 1973.
Integrity, Quality and Unmatched Service.

 

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