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Heater Core Leak

Fatima Rangwala
Has your vehicle been hurtled into a heater core leak? If yes, then this story will tell you the reasons for the leak along with some uncomplicated ways to fix the leak in your vehicle.
In liquid cooled vehicles, a heater core is a little radiator sort of car component that helps pass hot coolant through it. Separately, there is an electrical blower, which pulls in the air through the heater core and in turn blows back warm air into the passenger's compartment. Most of the fuss about core outflow starts from this coolant passage.
But this is the basic concept behind a heater core, in case you are a reader who isn't from a technical background. Pardon me, all you technical heads, for elaborating in such depth. I am beginning to sense the restless taps of your foot on the floor! Hence, I shall cut short and head for the hills to primarily state a few symptoms of a heater core outflow.

Symptoms of Leaking Heater Core

Fog: If the vehicle's windshield fogs up on starting the engine, it is a sign of leakage from the heater core. Thus, it's time to replace it.
Passenger's Board: This is another definite sign of a leak where the passenger's side front floorboard gets all wet.
Failure of the Device Itself!: This is the most overlooked reason for the leak. The device fails to supply the heat when the blower is switched to its extreme.
Cold Heater: After a sufficient running and warming up of the engine, if the heater is switched on and still fails to supply the heat, then this is the sheer sign of a heater core outflow.
Erratic Functioning: Erratic functioning is the jump of the heating system between hot to cold and vice versa. This action results in the loss of considerable amount of heat from the system.
Leaky Core: It's possible for a heater core to dysfunction at the heater hose connections or develop cracks in its core. This action will subsequently distribute the engine coolant into the surrounding areas. Those areas can be the engine's compartment or the car's interiors.
Dull Warming Up: Generally any vehicle barely takes any time to attain a few minutes of idling. But in case of a vehicle, taking good amount of time, say 10-15 minutes, to attain an idling state, signifies a heater core outflow. Thus, the normal functionality of the heater comes to a standstill.
Noise: Even a naive like me could tell about the heater core outflow by simply listening to the noise of the entire assembly. A normal working system apparently should be 'noise-free'. If the system makes a clanking or non-metallic abrasive noise after it starts, then definitely you need to first look for the state of the heater core.
In olden days, the device units were made of brass and other solid substances. These units were somehow difficult to manage and install. However, in modern times, the fabrication is of plastic and aluminum. These are durable materials, which literally take care of the device during the installation and usage.
The most expected reason for the heater core to leak is the input/output lines, just where the heater hose connects the heater core. It also happens that during some leaks, the entire passenger's front floorboards get soaking wet. In order to simply avoid such mishaps, as the clichéd phrase goes; prevention is better than cure.

How to Repair a Heater Core Leak

The moment these tiny radiators begin to act finicky apart from its usual working way, it's time to call for a mechanic. Merely reading some replacement instructions isn't going to get your job done. With the help of a mechanic, replace a bad heater core in the most skillful way.
Perhaps, once you see how it's done, the next time the system gets buggered up, the instructions given below will assist you well. But for now, spend a few dollars over the car repair work and get it done, ASAP!
Required Materials
  • A Hose Repair Kit
  • Utility Knife
  • Radiator Stop Leak Additive
Quick Procedure
  1. As a mechanic would be there at your service, with his help add a can of radiator stop leak additive to the vehicle's radiator.
  2. Now run the car's engine for just a few minutes. This will help distribute the fluid in the entire system.
  • After performing the step above, gently disconnect the accessible heater hoses that are obviously attached to the heater core. You have to perform this step just to ensure that the stop leak additive has fixed the leaking or not. One must perform this step very skillfully because here is where you are actually learning how to stop a leak.
  • Once that is done, reconnect the hoses back to each other. Do this using the new plastic hose connectors, which measure up to ¾'' or 5/8'' .
  • In case the new hose clamps aren't accessible, cut it at the point of entry and reconnect them using connectors.
Now in spite of you having these easy steps of fixing the leakage, you might want to DIY (do-it-yourself)! But I still suggest that if you are naive in doing a car job, believe me you don't want to get stuck in between a half-finished repair!