How to Change Your Heater Hose

Things You'll Need

Hoses and Hose Clamps
Gasket Sealer
Adjustable and Slip Joint Pliers
Screwdriver
Anti-Freeze

There are many reasons why a vehicle may have coolant leaks but the most common reason is because of heater hoses. Hot coolant enters and leaves through these hoses and into the interior of the vehicle. They also carry coolant between the engine block, heater core, and radiator.

Over time these hoses become brittle and crack or break. These hoses should be replaced every 4 to 5 years. Check the hoses by giving them a good squeeze. If they feel hard, soft, or swollen they should be replaced as soon as possible.

Warning: DO NOT perform this task on a hot engine. Make sure the engine is cold otherwise accidental burning of the body can occur and may cause serious injuries.

Steps

Drain the radiator first by removing the petcock fitting at the bottom. Be sure to place a bucket or a drain pan underneath to collect all the fluid. If this engine coolant is not going to be used again, dispose of it quickly because it’s very poisonous.
Use either a screwdriver or pliers to remove the hose clamps from the old hose. Using a twisting motion, pull the hose carefully from its fitting.
Once the old hose has been successfully removed, apply a small amount of gasket sealer to the fittings to ensure a tight seal with your new hose. Be careful not to apply too much sealer as it will get clogged in the new hose.
Place the clamps on the hose and install them. Make sure when installing the new hose that the ends slide far enough over the fittings so that the clamps can be installed properly.
Make sure the clamps are fastened properly and fill the radiator with coolant. Start the engine and check the coolant system for any possible leaks. Also, once the engine reaches normal temperature check the fluid level.

Need Automotive Tools?

Need some tools for your car? Go to CDM Tool Sales for ShopPro socket and ratchet sets, wrenches, and more!

CDM Tool sales- for all your hardware needs!

Tips

When removing the heater hose from the heater core, make sure not to pull or twist too hard as this will break the hose and you will have to replace the heater core. Split the hose from end to end with a box cutter and carefully loosen the hose then remove it.
Measure your old hose before removing it. Take the measurement of the length and the inner diameter. The standard diameter sizes of hoses range from 1/2”, 5/8”, to 3/4”.
If the old clamps look corroded and weak, replace them as soon as possible.

<<Back to Automotive Articles