How to Replace a Heater Core in Under 5 Hours

Replace a Heater Core

A heater core is that thing in your car that looks like a radiator which is used to heat your car’s passenger cabin. This small radiator is located under the dashboard of your car which is made up of conductive aluminum or brass tubing with cooling fins that increase its surface area. If the coolant system is not replaced or flushed regularly, this piping (tubing) may clog up and the heater core may not work properly.

Another possibility is a leak in one of the connections to the heater core that will need replacement of this unit if the leak becomes unrepairable. If this should be the case, you can do it by yourself and avoid paying a large amount of fee for its replacement. In this article, we will teach you how to replace a heater core in under 5 hours or less.

These are the things that you will need

    • New heater core

    • Liquid coolant

    • Catch basin

    • Stainless steel hose clamp

    • A set of socket

    • Wrench set

    • Screwdriver set

    • Safety goggles

    • Safety shoes

    • Safety gloves

Here’s how to replace a heater core

Note: Before you start, please make sure that you are wearing a proper personal protective equipment (PPE) like safety shoes, goggles, and gloves.

  1. Park your car on a level ground and set the emergency brake on. As another safety precaution, remove your battery connection to avoid dislodging the air bags on the dashboard of your car. This will also prevent electrical shock. Be sure also that your engine is cold before you start working.
  2. Drain the coolant from your radiator by releasing the radiator cap and loosening the radiator drain valve. Have your catch basin ready for the draining.
  3. If your car has a common housing (sometimes called the plenum) for both AC evaporator and heater cores, you have to discharge the AC’s refrigerant (if not, you can go straight to the next step). After discharging, disconnect the heater hoses and other AC equipment.
  4. Disconnect the heater hoses using a screwdriver and remove them from the fittings.
  5. Remove the top dash mounting screws after you remove the heater’s hoses. Be sure that you remove first any hardware on the top of the dashboard which is usually screwed along the windscreen’s base. The side of the dashboard for most cars, however, has a pop-up assembly, so you can open it up easily by using your hands.
  6. Once the top dashboard screws had been removed, you now have easy access to the lower mounting bolts of the heater housing. Remove these bolts. Most cars need to remove the center console to gain access to the middle installed bolts.
  7. By using an appropriate socket or screwdriver, remove the installed screws so you will have an access to the lower steering column installed bolts.
  8. Lower the steering column of the car on the driver’s side to be able for the dashboard to be rotated so you have a wider working area. Remove the bolts that support the column from the dashboard assembly then let this piece rest on the driver’s seat giving you ample space. Then remove the dashboard’s installed hardware to the left.
  9. At this time, the heater hoses should be removed, then remove the dash mounting bolts, including the foot shields, knee bolsters, and the center console. Additionally, most cars are equipped with access panels that allow the heater core to be replaced with a minimum of dismantling.
  10. When the stumbling blocks have been removed, you can now see that the heater core housing is easy to remove.
  11. Then, remove the control cables and the vacuum lines from the heater while remembering where these cables and lines are located so you can place them in their proper location when re-assembling a new heater later. While some car models have the blower motor wiring connected to the wiring of the heater, remove the connection first.
  12. You can now remove the heater core housing’s mounting bolts and screws using a screwdriver.
  13. Go now to the engine bay. Here, you can remove the mounting bolts of the housing of the heater core. Remove also all the hardware that supports the heater from the engine firewall, including windshield and distribution ducting. Once you have done this, the heater core housing will be free from the car and its removal is now easy.
  14. Then remove the heater housing with care. When removed, put this in a spacious area where you can work on its dis-assembly with ease.
  15. There are several screws that mount the heater core to its house. Carefully remove them one by one using your screwdriver set.
  16. After you have removed all the screws, pull the heater core gently and separate it from the housing.
  17. Once you have removed the heater core from its housing, you can now install the new heater core that you have purchased. Make sure that the new one is perfectly matched from the old housing.
  18. After you have installed the new heater core to its housing, you can install the new assembly by reversing what you have done in disassembling the unit. Be sure that you check all the necessary gaskets, insulation, wiring, cables, and seals.
  19. When you are finally done reassembling the new heater core (be sure that the hoses are attached and clamped properly) you must fill your car’s radiator with a new coolant the same type as before. You can dispose of properly the old coolant that you drained. Make sure that the radiator is properly plugged and the drain valve is installed.
  20. When you are finished reassembling the new heater core into its original place in the car, you can reconnect the car battery’s terminals that you have disconnected prior to the dis-assembly.
  21. When everything is set in place, run the engine of your car in idle and wait for the proper time that the engine gains its operating temperature. Then check the newly installed heater core system if it does not leak (tighten the clamp on the hoses if it does leak) and if it is now giving heat to the cabin.

Here are some honest tips

Here is the list of Amazon Prime’s best-selling heater cores. These are good choices as a replacement unit for your ailing heater core. Choose the one that will fit your car.

  1. Spectra Premium 93013 Heater Core (by Spectra Premium): Fully brazed aluminum design.
  2. ACDelco 22728343GM original Equipment Heater Core (by ACDelco): Ant-corrosive alloy material.
  3. TYC 96051 Replacement Heater Core (by TYC): Fins and tubes are made from high-grade aluminum for lightness and anti-corrosion properties.

While for an ideal coolant, try the Prestone AF2100 Extended Life 50/50 Antifreeze. This coolant mostly fits current models of cars and light duty trucks. Also available from Amazon.







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Did you enjoy this tutorial? How to replace a heater core can be as easy as you might think. Expert mechanics can do this quickly under 3 hours depending on car models. But for first timers, with the help of this article and the instruction manual on their possession, a 5-hour work is fairly enough.

This procedure covers basic types of cars and may slightly vary depending on car model. Allowing yourself to explore your car can save you precious dollars in reparation and maintenance. But be cautious enough to let the expert mechanic have a hand on your vehicle when necessary.

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About the author

Carolina - Care My Cars

Car, from a long time ago is the main transport vehicle for people which help to move faster and protect users from the unstable of weather such as sunlight, heat, or rainy. So that, the demand of car and the search for the best and a suitable car in the market are higher than ever and you also are one of the people who is looking for the answers from the market. Welcome to and I hope that my articles can help you to solve the problems that you are in with the most effective way. Donate: - Bitcoin (BTC): 1Eoz8vhfAjD4cCrq2jec3V38mmaHehedXU - Etherium (ETH): 0xd10809ae634117bf6c52Af884a8bc8B84D436e3b - BicoinCash (BCH): qqp4yjqx2g57exes0stsnkgk5e9uyu5clvrjj4ew44

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