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Knowing when to replace a car radiator can help you protect your vehicle from serious damage. Below, we’ll examine the role your radiator plays in your car, and tell you what signs to look out for when the time comes to change out this crucial component. We’ll also offer insight that can help you determine whether you should tackle radiator problems yourself or turn them over to a skilled mechanic.

What Makes a Radiator Important

The radiator is part of your car’s cooling system, and it plays a leading role in the way your vehicle performs. A car’s engine generates a great deal of heat when it’s running. If left unchecked, this would cause the vehicle to quickly overheat when it’s on. Coolant is used to prevent this from happening. This fluid absorbs the heat and transports it out of a car’s engine block, sending it directly to the radiator.

Once the coolant arrives at the radiator, it passes through thin metal fins. This process allows the coolant’s heat to be released from the vehicle to the air outside. Some radiators use a fan that helps move hot air outside the vehicle quickly.

When to Replace a Radiator

If your vehicle exhibits any of the following signs, it may be suffering from a problem that calls for a radiator replacement:

  • Steam billowing from beneath the hood: If you notice steam emanating from beneath the hood of your car when it’s in motion, it means your engine is overheating and that your car’s radiator isn’t doing its job. Overheating can result in permanent damage to vital engine components.

  • A temperature gauge that indicates rapidly rising or unusually high temperatures: Your car’s temperature gauge measures coolant heat. If the gauge’s dial indicates rising or unusually excessive coolant heat, this could signify a problem with your car’s radiator.

  • Rust on the radiator’s exterior: The radiator works by passing hot coolant through its pipes. If the radiator is rusty, this could create blockages that hinder the cooling process.

  • Brown debris within the radiator: Your car’s cooling system uses rubber and metallic components. If these rust or break down, they’ll deposit brown debris within your car’s radiator. Over time, this can prevent the radiator from functioning properly. This problem is common with radiators and coolant lines that are more than 15 years old. Using a coolant refill tool to replace old coolant at manufacturer-specified intervals is a good way of reducing the amount of buildup in your radiator.

Common Radiator Problems

The following problems are commonly seen in radiators:

  • Radiator rust and corrosion.

  • A leaking or clogged radiator core.

  • A broken or malfunctioning radiator fan.

  • Leaky coolant lines or a leaky coolant tank.

If your car’s cooling system has a leak, and you’re able to easily identify it, you may be able to fix the problem yourself. The same is true if you’ve determined that you have a faulty radiator fan. However, a rusty radiator may need to be replaced, and this task is more complex. Unless you have experience in this area, turning the problem over to a qualified mechanic may be the simplest solution.

Your car relies on its radiator to function effectively. If you notice any of these problems with your vehicle, they could be a sign that your vehicle’s radiator isn’t doing its job.

Check out all the heating & 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 when to replace a car radiator, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

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