Radiator Hose Replacement

Easy step by step guide on how to replace an automotive radiator coolant hose, though appearances may vary the process is similar for most vehicles.

Difficulty Scale: 4 of 10

Begin with the vehicle parked on flat ground, in park with the emergency brake set, engine cold.

Step 1 - Open the radiator cap to release any residual pressure and to allow the coolant to flow freely when drained.

Removing Radiator Cap

Step 2 - Next, locate the radiator drain plug which is where the system coolant will be drained from. (Note: Some cooling systems do not have a drain valve, the lower radiator hose should be used to drain the system.)

Locate Radiator Drain Plug

Step 3 - Once located, loosen the drain plug allowing the coolant to flow into a catch basin, tighten the drain plug once the coolant has completely drained.

Draining Coolant

Step 4 - Once the coolant has drained, identify the radiator hose that needs to be replaced.

Upper Radiator Hose

Step 5 - At each end of the hose, clamps are used to secure the hose to the radiator and engine. Pliers/channel locks or a hose clamp installation tool can be used to loosen the clamp, a twisting motion will help loosen the seal of the hose.

Removing Upper Radiator Hose Clamp

Step 6 - Remove the remaining hose clamps at the opposite end of the hose.

Removing Upper Radiator Hose Clamp

Step 7 - After the hose clamps have been removed from the clamping area, use a pick or screw driver to "break" the seal by forcing it between the hose and fitting.

Hose Removal Tool

Step 8 - Next, grasp the hose and twist the hose which will fully release the hose seal.

Twisting Motion

Step 9 - The hose will pull off the fitting, a small amount of coolant maybe present which is normal. (Note: A small amount of coolant can be trapped on top of the closed thermostat.)

Radiator Hose Removed

Step 10 - Match the new radiator hose to the old hose to ensure a proper installation.

New Radiator Hose

Step 11 - After transferring the hose clamps to the new hose and cleaning fitting ends, push the new hose onto the fitting while squeezing the clamp open, repeat this for action the opposing hose end. (Note: Replace any clamps that are broken or worn.)

Install New Radiator Hose

Step 12 - When installing the hose clamps position the clamp in front of the fitting ridge, this ridge is designed to help the hose and clamp stay secure under pressure. The alignment of the clamp should be "square" (not crooked) to hold pressure needed to successfully seal.

Clamp Position

Step 13 - Install any shields or bracing that was removed in the repair.

Install Shields

Step 14 - Once the new hose or hoses have been replaced, refill the radiator with coolant. Start the engine and allow to warm up to operating temperature which will allow the thermostat to open, continue adding coolant until the level is between the indicator lines on the coolant reservoir.

Refill Coolant

Step 15 - When the job is complete and the cooling system has been filled, reinstall the radiator cap and tighten, allow the engine to run while checking for leaks. If leaks are present release the system pressure and reposition the clamp.

Radiator Cap

Helpful Information

Most radiator hoses are made out of silicone based rubber that offers resistance to hardening and cracking. Hoses can also show signs of bulging when they get close to failure, others can fail with no warning. High quality radiator hoses have multiple-ply construction with a fabric mesh reinforcement depending on the application.

Hoses Need to be Replaced When:

  • Showing signs of bulging
  • Cracked and dry
  • Hoses are more than 8 years old
Tools and Supplies Needed

  • Flashlight
  • Jack stands
  • Floor jack
  • Coolant
  • 5. 6. Hose clamps
  • Replacement radiator hose
  • Fluid catch basin
  • Pliers/channel locks hose clamp removal tool
  • Screw driver set
  • Pick Tool
Best Practices

  • Always clean the hose fitting before installing the new hose.
  • Recheck the cooling system after a couple of days to ensure proper operation.
  • Use new hose clamps.


Written by
Co-Founder and CEO of
35 years in the automotive repair field, ASE Master Technician, Advanced Electrical and Mechanical Theory.


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