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Your vehicle’s cooling system is tasked with keeping your engine from overheating. It consists of several parts, including a radiator, water pump, thermostat, heater fan, heater core and radiator hoses. When a radiator hose fails, the cooling system eventually shuts down. The signs of a bad radiator hose are easy to detect, once you lift the hood and search for the problem.

Top Signs of a Bad Radiator Hose

1. One or More Broken or Separated Hoses

A working radiator hose should be firm to the touch and fixed to each clamp. A hose may soon break if you notice swelling, cracks, holes or leaks. Also, a hose may be in fine condition, but it may have separated from its fitting or a clamp may have broken or become undone.

When performing an inspection of the cooling system, check every hose present. It begins with an upper radiator hose connecting the radiator to the water pump. You’ll also find heater hoses, with the first serving as a feeder to the heater core and the second as a return from the core to the thermostat. You’ll also find a bleed hose, a steam hose and a lower radiator hose. Change one defective hose and you may find one or more of the remaining hoses are ready to fail, as well.

2. We Have a Leak

Before a hose breaks, it may leak. The first sign of a leak typically occurs when you park your car and notice fluid on the pavement near the engine. If the fluid is green, then antifreeze (coolant) is the most likely culprit.

Raise the hood and begin your inspection of the cooling system. Check each hose as well as the fitting and clamps. If you don’t find a leak, inspect the radiator and water pump as either one of these components may have failed.

3. The Dashboard Tells You So

Your car’s instrument panel sits in the dashboard behind the steering wheel. Beside the usual speed, temperature, performance and fuel gauges is an embedded digital panel. You may not pay attention to it until a symbol suddenly appears on it.

Once known as the “check engine light,” the symbol may take on other shapes. The symbol for low coolant looks like a thermostat sitting on waves. If it appears, then immediately pull off the road and check the coolant reservoir. If you’re losing coolant, a radiator hose may need your attention.

4. The Engine Is Overheating

Always keep an eye on your car’s engine temperature, which is tracked on a gauge located within the instrument panel. It should be fixed midway between C (cold) and H (hot).

If the register moves to hot, then your engine is in danger of overheating, which can cost you thousands of dollars in repairs. Something may be wrong with the cooling system, so pull over immediately and shut off the car. You can inspect the cooling system, including the hoses, while waiting for help.

Clearly, a broken radiator hose is no small matter. If left unattended, it could lead to a breakdown and cost you expensive repairs. In a worst-case scenario, a piston can weld to a cylinder, destroying the engine.

Cooling System Essentials

If your car’s been overheating, use these four signs to see if the issue could be a failing radiator hose. Radiator hoses are usually affordable and easy to replace, which means there’s no excuse to let a faulty one potentially ruin your car’s engine. Besides checking your hoses, following your owner’s manual for guidance on maintaining your entire cooling system will help you keep your engine cool for years.

Check out all the heating and cooling products available on NAPA Online or trust one of our 16,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on how to spot a faulty radiator hose, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

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