How to: Replace your heater core, the easy way

[El Duque]

So now that our '06-'10 Explorers are getting up there in age and mileage (I know mine is, 167,000) you might have to replace your heater core. I started hearing the engine fan roaring on the highway, I figured cause it was hot weather. Then I check the coolant and it's low. Fill it and go a week, low again, I'm like WTF. Then on Friday morning, I see vapor coming out of the dash vents without the heat even being on. I knew for sure it was the heater core then.

So I started poking around the forum and only saw bad news. That the A/C system would have to be drained and disconnected, so that the heater and A/C evap could be removed as one piece. I did see a video where someone cut the tubing and slid the core out from the bottom and use some hose and hose clamps to connect the new one. I didn't want to do that but I figured I would as a last resort.

So, the dash does have to be pulled. It actually wasn't that hard to do. Someone mentioned in a thread here about using some long M8x1.25 bolts so that the dash could be pulled out and still be supported. I did that and it was a good idea. I have the OEM service manual so if you need more detail let me know, but here's an overview.

I pulled the driver seat for extra room
I also pulled the center console cause there is a long wire running from the dash to underneath the back of the console. I actually cut a slit in the carpet for easier access
I pulled the instrument panel, radio, A-pillar covers, parking brake release handle, steering wheel and steering column pinch bolt. I used a piece of gorilla tape to stop the clock spring from rotating.

So after pulling the dash, I was presented with this

There is a black cover covering the heater core tubes, so I removed that. Then, there are 8 or 9 bolts that hold the heater core/evap box together, along with 4 bolts on the bottom for the heater core cover. I was then able to separate the box.

That was it! I read on here somewhere that the factory service manual was written to use a few steps as possible, so I couldn't believe it said to drain and disconnect the A/C and pull the whole thing as one unit. I hope this helps someone else, cause I know I was sweating bullets.

 

[94Eddie]

That doesn't look like a fun job. While I had that much dissembled I would replace some other HVAC components like the blend door etc. to hedge my bets from doing future repairs.

 

[Rick]

@El Duque I set you up with a 3 month Elite membership for your how to article

 

[El Duque]

@El Duque I set you up with a 3 month Elite membership for your how to article

Thanks Rick! Appreciate it!

 

[El Duque]

That doesn't look like a fun job. While I had that much dissembled I would replace some other HVAC components like the blend door etc. to hedge my bets from doing future repairs.

I already did a blend door a few years ago, without removing the dash. How I don't know. I had to bend my hands in ways that I didn't think was possible lol

 

[zerodevil]

I might have to do this before winter. My front heat has been terribly bad, lukewarm at best, since I bought the vehicle. There are times in the winter that the defrost cant keep up with the cold windows. I have been riding the rear heat a lot to heat the cab, as its fire hot. I'm going to try a really hard soak with radiator flush, and then a back flush to see if that solves my issue first. But, this guide could be a massive help If I go to do the job in a month or so. What do you mean you used a piece of tap to stop the clockspring?

 

[El Duque]

I might have to do this before winter. My front heat has been terribly bad, lukewarm at best, since I bought the vehicle. There are times in the winter that the defrost cant keep up with the cold windows. I have been riding the rear heat a lot to heat the cab, as its fire hot. I'm going to try a really hard soak with radiator flush, and then a back flush to see if that solves my issue first. But, this guide could be a massive help If I go to do the job in a month or so. What do you mean you used a piece of tap to stop the clockspring?

If you take off the steering wheel, the clockspring is exposed. It's not supposed to be rotated, so I taped it to the steering column

 

[Blackhawkxx]

How many hours did you have in this? It doesn't look like a fun job at all.

 

[El Duque]

How many hours did you have in this? It doesn't look like a fun job at all.

I'd say about 8 hours, but I split it up over the 3-day weekend. It actually wasn't that bad. Just the fact that the A/C evap unit didn't have to be removed pretty much removed all the stress. If I had known that going in, I would have had a smile on my face!