How to Tell if Your Car Radiator Needs Replacing

A Car Engine

Whether it is on the roadways of Lombard, Illinois, or anywhere else, an overheating radiator isn’t anything to ignore. While most times, the radiator will outlast the time you own your car, when your mechanic recommends a radiator replacement, you shouldn’t take that advice in passing. 

What purpose does the radiator serve?

Your vehicle’s radiator is a key component to the cooling system for the engine, and the engine is a key component of you getting from point A to Points B, C, D, etc. The radiator is like your body’s hypothalamus gland. When your body gets hot, the hypothalamus gland cools you down and the radiator does the same for your vehicle’s engine. 

Simply put, the main function of the radiator is to disperse a mixture of coolant (antifreeze) and water throughout the fins. This releases the excess heat the engine has built up. It also takes in cooled air and passes it throughout the entire engine.

So, when the hypothalamus gland equivalent of your vehicle, the radiator, isn’t working properly,  a radiator replacement is needed if it can’t be repaired. 

Can a car radiator be repaired? 

Just like the hypothalamus gland can be reset with certain foods and therapy, the vehicle’s radiator can sometimes be repaired. A radiator that is leaking may be repairable, depending on where the leak is located. In most cases, however, a mechanic will recommend a radiator replacement due to the high temperatures and pressure a radiator is exposed to while driving.

Is radiator replacement a big job?

Well, it isn’t the easiest part of vehicle mechanics, with the average radiator replacement job taking between 2 hours and up to 5 hours. The time to disconnect and remove the existing radiator can be complicated, and installing the radiator replacement can be complicated as well. 

What does a radiator replacement cost? 

The make, model, and year of the vehicle will have an impact on the cost of a radiator replacement, but on average, you can expect to pay anywhere between $400 and as much as $900 or more. This includes the radiator replacement and the labor to remove the existing one, install the new radiator, add new coolant, and test the radiator for leaks. The radiator replacement itself is the least expensive part of this. The expense is in the labor and the intensity of the job.

Can you do your radiator replacement?

A mechanically inclined person can do their radiator replacement and save the labor cost of a mechanic doing the work. Having it done by a professional can prove the labor costs are worthwhile for many people though, keep reading to find out why. 

What does a radiator replacement job entail? 

As with any car repair, safety should be the first concern for you and your vehicle. With a radiator replacement, there are electrical connections that need to be disconnected which can be done by disconnecting the battery. If the battery isn’t connected, none of the electrical features of a vehicle can work. (Follow this blog for a car battery replacement!)

If you put the vehicle on jacks or ramps, make sure you chock the wheels and put the emergency brake on. Allow the engine time to cool before starting a radiator replacement job. There are sharp edges in and on the car engine compartment, and the radiator itself. Wearing protective eyewear and gloves is recommended when doing a radiator replacement. The steps for this project include: 


Before you assume you need a radiator replacement, inspect the entire coolant system for the problem. This includes inspecting the overflow cap and the radiator. Inspect the belts and hoses to see if any are broken, cracked, or otherwise damaged. Inspect the fan clutch that is located between the radiator and the water pump motor to make sure there isn’t any play within the bearings. And check the thermostat! Before you go to all the work for radiator replacement, the overheating problem could be as simple as replacing the thermostat. 


If you determine a radiator replacement is needed, you’ll to drain the fluid. Start by placing a plastic container under the radiator then remove the radiator cap. Next, either remove the bottom hose or open the petcock valve. This will allow the coolant to drain. 


After the coolant has completely drained, this shouldn’t take more than 10 minutes, and remove all clamps, hoses, and bolts. This includes the upper and lower hoses, the fan and fan shroud, cooler lines coming from the transmission, the mounting bolts to the A/C condenser, and all radiator mounting bolts. Keep these parts organized, making tags on each component and where it came from can be helpful. 


Now it is time to remove the radiator, usually done by lifting it up and out. Now will be the time you discover you didn’t disconnect something! 


You are now ready to install your radiator replacement. This will be reconnecting and installing all the things you removed earlier. (You’ll wish you tagged these parts now if you didn’t!). 


Make sure to close the petcock, caps, and valves on the new unit and that it is bolted in correctly along with the fan and fan shroud. Use distilled water, read the label on the jug of coolant, and add the appropriate amounts to create a 50/50 mixture unless the owner’s manual suggests differently. 


During a radiator replacement air can get trapped within the cooling system. This needs to be bled out to prevent the engine from overheating.  To do this start the vehicle and let it run for approximately 20 minutes. Watch the heat gauge to make sure the engine isn’t overheating and watch under the hood for leaks.

Keep Things From Heating Up! 

Some indications will tell you that either radiator repair or radiator replacement is necessary, such as: 

  • Coolant Leaking: You may notice puddles under the front of your vehicle on the ground. Smelling it will tell you if it is coolant. 
  • Overheating Engine: If you notice the heat gauge is reaching the high side and staying, your vehicle may need a radiator replacement or repair. 
  • Sludge Forming: When you have your oil changed, the technician will typically check all fluids. If they notice the cooling system has a build-up of sludge, they will recommend having the radiator inspected by a mechanic. 
  • Sweet Smelling: If you notice a sweet sick-like smell coming from your car, have a mechanic check the radiator.