Heater core replacement on non AC car??

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Joined
Jun 27, 2012
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Location
Rhode Island
My Car
1972 Mustang Convertable
302 v2 FMX 2.79 rear end
I kinda broke one of the heater core tubes while trying to replace the heater hoses, the copper tube came out with the hose!!! not good.

so after looking around on here all of the threads are for AC cars, mine is a NON AC car, do I still have to remove the heater box?

if there is an other method to replace the heater core please share.

also any recommendations on a quality replacement heater core? Autozone and Advanced auto, also Napa have them for $20-$25

then I looked up different Mustang sites and they want $45 plus.

I'll also once mine is out, I will check the condition and maybe have it repaired at a Radiator shop (maybe).

Thanks

 
I'm sure you will have to drop the box and disassemble it...abt 1hr

to drop +2 to disassemble.

Mustang websites have seal kits for the box flappers etc.

Check www.Rockauto.com for a good price on the core.

I wouldn't mess with fixing it as replacements are cheap.

Consensus is brass is better than aluminum.

Good Luck

Paul

 
I found it easier to remove the glove box, kick panel, front seat, carpet and loosen the dash to remove the heater box. I am not the best mechanic, Took me about eight hours in and out.

image.jpg

 
My wife ordered a new heater core (all brass, not aluminum) now as soon as it comes in, I'll start the disassembly :(

this is one project I'm not looking forward too do!!

I have a couple of days before I tackle this project, any shortcuts are welcome!!

 
what makes it murder on a A/C car is you have to drain the A/C system and take it apart in addition to the heater core hoses. there is also additional electrical and vacuum lines and the box itself is much larger on the A/C cars making the tight clearance even worse. plus all that makes the box weight a lot more.

on a A/C car if you work carefully it can take more then 2 days.

It took me a week just to rebuild my box, i had to fix fiberglass damage and then rebuild all the flapper doors and source 2 doors that were eaten away from rust.

i had to source new vaccum motors as well.

once i had the box 100% restored then it took me 2 days to get it back behind the dash without breaking anything.

the heater only cars have less parts so on that it is easier.

the heater boxes are deceptive because you assume the access panels on the boxes mean you can service them easy. but those doors and panels are just to make them easy to assemble on the bench outside of the car and do nothing for you as far as maintenance.

 
I've taken mine out twice to change heater cores. The first time took a long time because I didn't know what I was doing, but the second time I reckon I had it out and back in in about an hour.

Remove glovebox liner.

Remove passenger seat.

And here's the hot tip ----> remove the lower plastic floor vent (pictured below) from the heater box before trying to extract the unit. The floor vent adds just enough extra volume to stop the heater box from being maneuvered and pulled through the gap underneath the dash; when the vent is removed first then the heater box fits fairly easily through the gap under the dash.

From memory there are two or three plastic screws or clips that hold this vent on - these clips broke when I removed the vent but I replaced them with a couple of self tapping screws which worked perfectly to reattach the vent after heater box re-installation. Taking the vent off the heater box before removal is the main reason why the job went so much quicker the second time around.

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While I have not done this job, I did remove the heater box on my car when I converted to aftermarket AC. Above advice is great, and I'll add to it just a bit. The fresh air vent assembly is held in by 3 small bolts and the cable is held in place with one screw. Pull these and the amount of room you open up for access purposes is significantly improved. I'd go ahead and fold the carpet back and away and do my best to drain out as much coolant as possible to minimize the mess. You can snake a piece of vacuum line into the heater core and use a wet dry vacuum to drain most of it out.

While the box is out, you may want to replace seals inside it as well as the heater core.

Or . . . it is about 1/3 of the work that the AC conversion requires-it would be a good time if you were interested in such a conversion.

 
I took the heater box out yesterday, sorry I didn't recorded it like I said, but I took some pictures.

I used the tips I got on here and it took me about 45 min to get heater box out, not bad at all, all I had to remove was the glove box, and glove box insert, I never removed the passenger side seat but I did cover it.

Then I disconnected the control cables, the motor wire, and radio antenna wire (it was in the way)

I unbolted the fresh air intake (3 bolts to the heater box, 1 bolt to the cowling) then I disconnected the defrost duct (1 snap pin) and the lower duct (2 snap pins).

Then under the hood I removed the 4 mounting bolts on the firewall, 3 on the passage side, and 1 on the driver’s side.

Then I lowered the heater box, to free it up, then I flipped it on to its face (the fiberglass side) and it slid right out the car.

Once out of the car, there are 4 screws for the heater core access panel, and the heater core slid right out. I saved all of the sponge like gaskets, to reuse (they were in very good shape), I then removed the motor and pressure washed the heater box, it’s amazing what gets in there (dirt, leaves, mice nests)

All of the damper inside are in mint condition, and don’t bind up at all, so we are good in that department.

Now hope fully today or tomorrow I get the new heater core, I can reinstall it back in, and hope fully it goes in just as easy as it came out.

 
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