How To Fix A Leaking Heater Core? 2 Best Ways!

Do you want to know how to fix a leaking heater core? You probably smell the coolant inside the car, and it does not produce heat in the cabin or has foggy windshields. Then, presumably, there’s a problem with your heater core.

There are reasons why your heater core does not produce heat even if you have turned on your car’s engine or ran for a few miles, and maybe your heater hoses are leaking. 

how to fix a leaking heater core

Two methods can help you fix the leak in heater core hoses: bypassing the hoses or removing them and replacing them later with a new one. If you don’t know how to replace the heater hoses and you have to travel to the mechanic or use your car, you can bypass it in the meantime. But note that, in bypassing the hoses, you won’t have heat inside the vehicle. 


What Is A Heater Core?

A car’s heater core looks like a small radiator in your car, which passes the heat of your car’s engine. The hot coolant from the engine travels into your heater core and gives heat inside the cabin, while the outlet heater hose is where the cold coolant goes out from the heater core. Once again, the cold coolant travels and goes back into the engine again. That is why testing the capacity of your heater core requires you to run the engine for a few minutes. Are you ready to learn more about it and how to fix a leaking heater core, my friend? Please continue reading. 


Ways To Fix A Heater Core

Suppose you find out that the hoses from your heater core leak. You have two options to fix them: remove the entire heater core from your car or leave it and connect the two hoses. Removing the whole heater core will take time, but you can also access the vehicle, especially if you need to replace it if you do not want to remove the entire heater core. You can simply bypass the tubes!

Bypassing is a method wherein the inlet and outlet hoses are connected using pipe connectors if the leaks are mild. Bypassing also means no hot and cold coolant will go in and outside your heater, and your car won’t produce any heat or airflow. You can use this method for a shorter time until you replace them or until your mechanic arrives. On the other hand, if it is already winter and freezing outside, bypassing your heater core is not recommendable, as you need a higher temperature inside the cabin to travel safely. 


#1. Bypassing heater core

You have to connect the inlet and outlet heater core hoses. In this method, you must know about cutting the hoses correctly as you have to be careful with them. An incorrect bypass can cause your coolant to leak more than it was and cause further damage to your heater core. Aside from that, hot coolant can cause physical injury. To start, locate your heater core hoses. You can easily find them as they connect to the heater core, commonly placed in the firewall or away from the engine. As cars differ, you might place this differently from others. 

You can cut the hoses or remove the hose from the firewall. If you choose to cut the hoses, give at least a few inches away from the firewall for easy access. Wrap the area you decide to cut, put a cloth, and clip the hoses with a tool. Clipping stops the possible coolant from flowing and releases the clip after the cutting. You can also put a container underneath the car to prevent coolant from going over the surface.

Do the same procedure on both hoses, then connect a 180-degree plastic tubing, and it must fit tightly. If the 180-degree plastic tube is unavailable, you can use a PVC pipe instead. Refill your coolant and run your car’s engine. 


#2. Removing heater core

You need to remove the car’s dashboard to replace the heater core, y. Some vehicle requires you to remove the air-conditioning grating to access the dashboard. In removing the dashboard, be careful not to cut any wires or connectors. After this, disconnect the hoses in the heater core and use a Philip or flat head screwdriver o remove the screws or loosen the bolt. After removing the heater core, use a coupler or a hose connector and attach it to the inlet and outlet hoses.

You bypassed the heater core by removing it and securing a replacement if you decided to purchase a new one, especially if your heater core is old enough. Run the car’s engine and check if your vehicle overheats. If it doesn’t, you’re good to go. You may also be interested to know about the symptoms of a bad or failing heater core.


It’s A Wrap!

You now successfully learned how to fix a leaking heater core! You won’t be worried about the coolant leaking out of your car anymore, as you can now fix them by yourself and determine what type of bypassing you need. Isn’t that easy and quick to perform? Hope this article helped you understand the importance of heater core and bypassing methods. You may also want to read about how much to replace a heater core and how to fix a clogged heater core.

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