The radiator hose is part of your car’s cooling system, carrying the coolant to the radiator, where the fluid is cooled and then back to the engine to keep the vehicle from overheating. The upper hose attaches from the top of the radiator towards the top of the engine at the thermostat housing. The lower hose, pictured above, attaches from the bottom of the radiator towards the water pump of the engine.
Common Symptoms of a Bad or Failing Radiator Hose
If you suspect either of these hoses is failing, you need to look for these symptoms:
1) Leaking coolant
If you find a puddle of green fluid beneath your vehicle, there’s a good chance your vehicle is leaking coolant. Coolant mostly has a sweet smell to it and can come from a number of places including the radiator hose, the radiator drain cock, or the radiator itself. Since there are so many possible areas to check, it is crucial to have a professional mechanic diagnose the problem, and replace the hoses if necessary.
2) Engine overheating
Your vehicle’s engine should never be overheated. If you see this symptom, it means something is seriously wrong with the vehicle’s cooling system. Radiator hoses are mostly to blame, as they can crack and leak from years of exposure to high heat and pressure. If you allow the engine to continue to overheat, you might cause the engine to completely fail and your vehicle will no longer operate.
3) Low coolant
If your Low Coolant Light comes on, or you have to constantly replenish the fluid, there’s probably a leak in the radiator hose. This type of leak will also create those green puddles underneath of your vehicle, especially if the vehicle was parked for several hours. Driving on low coolant is not a good idea as if you can run out of coolant on the way to your destination your car can overheat and stall which leaving you stranded on the side of the road and causing severe damage to the rest of your engine.
4) Collapsed radiator hose
If you look under the hood and notice that the radiator hose has collapsed, it’s time for calling your mechanic. Hoses can collapse when they become soft or weak or, occasionally, due to a cooling system fault. No matter the cause, an inspection needs to be performed– a collapsed hose cannot flow coolant properly which can cause the vehicle to overheat and eventually leading to engine damage.
5) Radiator hose is broken
Radiator hoses can be broken in a variety of methods. If you feel comfortable, just inspect the hose for leaks, swelling, holes, collapsed, cracked, or wear. As soon as you find any of these, your radiator hose needs to be replaced. And, if you don’t want to check them yourself, just take your car to your mechanic to have a professional inspection.
How to Replace a Radiator Hose
The radiator hose is a crucial part of your vehicle’s cooling system. The hose carries the coolant to the radiator, where the fluid is cooled and then back to the engine to keep the vehicle from overheating. This helps your vehicle to operate at the perfect temperature and provides you with a smooth ride.
There are two types of hoses that connect to the radiator. The upper hose attaches from the top of the radiator towards the top of the engine. The lower hose attaches to the bottom of the radiator towards the water pump of the engine.
If the radiator hose of your car fails, it can cause loss of coolant and subsequent engine overheating. Overheating can lead to further engine damage. If you suspect that either radiator hose is failing, replace the faulty hose as soon as possible.
Part 1 of 2: Remove the leaking radiator hose
- Cooling system funnel(optional)
- Container or drain pan
- Protective gloves
- Autozone or Chilton repair manuals
- Replacement radiator hose
- Safety glasses
- Vacuum cooling system refiller (optional)
- Wheel chocks
Step 1: Remove the radiator cap. Wait till the radiator cap is cool to the touch. Then remove it and juts set it aside.
- Warning: Do not remove the radiator cap while it is hot! The system is under pressure and the cap might burst off, burning you with hot coolant.
Step 2: Drain the coolant. Put a clean container below the vehicle, right under the radiator.
Drain the coolant either through opening the drain petcock or by sliding back the clamp on the lower radiator hose (see the following step for the hose removal procedure).
Step 3: Loosen the hose clamps. Loosen the clamps at each of the end of hose. The hose clamps are usually either of the spring tension or screw tension design.
To remove a spring tension clamp, just squeeze it with pliers and pull it back on the hose, away from the connection. For removing a screw tension clamp, simply loosen the clamp with a screwdriver, then pull it back on the hose, away from the connection.
Step 4: Remove the radiator hose. Once you have the clamp off, you can remove the radiator hose through twisting and pulling it off the fitting.
- Tip: If the hose is stuck on the connection, slit it with the help of a razor blade. Do not cut so deep that you just damage the connection. After being cut, the hose can be peeled back and then can be discarded.
Part 2 of 2: Install the hose
Step 1: Slide clamps over the replacement hose. Slide the hose clamps over the replacement radiator hose but ensure not to tighten them down.
Step 2: Install the radiator hose. Slide the hose to the connector.
After that, position and secure the clamps at least 1/4 in. (6.35mm) from the ends of the hose. Check to make sure the clamps are located beyond the raised bead of the connector and then tighten them down.
Step 3: Refill the radiator. Close the drain petcock or just reinstall the lower radiator hose. After that, fill the cooling system with a 50/50 mixture of coolant and distilled water.
- Tip: The easiest way to make sure you are getting the proper radiator fluid mixture is to buy pre-mixed radiator fluid.
- Note: Some methods for bleeding the cooling system need filling the system during the bleeding process.
Step 4: Bleed the cooling system. Whenever you service the cooling system, you need to bleed it to remove air, otherwise overheating may result.
There are a few different ways for bleeding the cooling system:
Step 5: Top off the coolant. Top off the coolant in the radiator as well as in the reservoir. Then, just reinstall the radiator cap. Run the engine and check for any leak.
It will be good to replace the hoses every 5 years or for every 40,000 miles. If you see coolant (red, yellow or green fluid) on your driveway, get the car inspected for any leak immediately. Driving with leaking radiator hoses can lead to severe damage to the engine.