Heater core replacement Questions

[A_Code_Kiwi]

I'm about to replace the heater core in my '66 Stang and was wondering if anyones got any words of advice on what to do, what not to do etc. I tried a forum search and turned up nothing, so it either means it's so easy it's not worth talking about or no ones ever done it I'm hoping it's not going to be a PITA. Along with replacing the core I'm replacing the plenum as well as getting a new heater foam kit and heater hoses.

Any help would be much apprecited.

Cheers

 

[Stang_1973]

Well i am not sure as how its done in a '66 but it was a real pain to do in my '73. I used one of those how to books on classic stangs. It was totally wrong. Basically I had to figure it out myself. Someone told me I was going to have to disassemble my dash but I didnt.

First i took off the glove box door and box itself.
Then i dropped the heater box. I got a faceful of dust and leaves, yes, leaves.
Next I opened up the box by removing all the clips.
Then I took out the metal parts as it was impossible to remove the core by simply sliding it out.

I put everything back in the reverse order. I cleaned out what i could in the ducts ands stuff while I had everything out. I was surprised at how dirty it was in there.

 

[5.0ina66]

Pull the hoses off at the engine side and pull them through the holes in the firewall as you pull the heater box out.

Also, be careful when you take the nuts off of the blower motor; I think they were supposed to be one-use only items, and they deform if you aren't nice to them.

I've heard people complain about the job in a 65-66, but I've done heater core replacements that take more than one day. With the interior of my car stripped, unhooking the heater box, taking it out, and dissasembling it was a 20 minute job.

It is a bit of a drippy mess, even when you disconnect the hoses at the other end, so I could see how it would be harder with the interior in, but if you put some newspaper in the floor, or something, it shouldn't be too bad. Also, you may want to pull the passengers seat; it looks like that's the only way to do it if you're over 4' tall .
HTH
--Kyle

 

[Stang_1973]

It is a bit of a drippy mess, even when you disconnect the hoses at the other end, so I could see how it would be harder with the interior in, but if you put some newspaper in the floor, or something, it shouldn't be too bad. Also, you may want to pull the passengers seat; it looks like that's the only way to do it if you're over 4' tall .
HTH
--Kyle

Oh yeah this too. The darn seat made my back hurt as it was impossible to get postioning in there.

 

[65ShelbyClone]

I've heard people complain about the job in a 65-66, but I've done heater core replacements that take more than one day. With the interior of my car stripped, unhooking the heater box, taking it out, and dissasembling it was a 20 minute job.

People have no right to complain if they've never changed a core in a latemodel with A/C. It took me two days when I had my '89 GT.

The core in my prvious '65 was a comparative cakewalk. It might have taken me two hours tops and I didnt have a manual. I just pulled the blower box, opened that, removed the core, and reversed the procedure.....all while kneeling on ground and working from the passenger side. I'm 6'4" and know what its like having the climb under the dash...

 

[gjz30075]

Pull the hoses off at the engine side and pull them through the holes in the firewall as you pull the heater box out.

Not necessarilly. If the heater hose's age is unknown, you might just want to cut them off near the firewall. It'll certainly make removal much easier. Either way, after fitting hoses after fitting a new core, they'll have to be snaked back through the holes. A two man job.

Anyway, the only mountings for the heater box is the blower motor nuts and a small horizontal flange way up behind the glove box. Then its just a matter of removing the cables. Oops, don't forget the resistor plug at the front.

 

[krash kendall]

Very easy job for one person to do. Remove the fan motor and oil the motor shaft behind the squirrel cage while you are at it. They have a tendency to seize up, or get sticky at the least, and start blowing fuses.

 

[66stangbluework]

I actually just did this today, I also put in the new seal kit, its raining now so i just have to wait for it to stop before I can put it back in. It was real easy.

I've read on the forum about people putting a valve in the heater hose to stop the flow in the summer because it causes alot of extra heat, anyone know more about this specifically?

 

[limey66]

Piece of cake.

I've had the heater in and out of my 66 three times now (long story), but if it takes you more than 30 minutes to get it out, you're doing something wrong...

 

[iskwezm]

A little tip that I did on mine was I cut off the tubes on the old core and used short peoces of hose to put them through the fire wall,so the new hoses dont get clamped inside the car but in the engine compartment instead,makes removal easier for next itme.

 

[limey66]

Now that, is good thinking...

 

[1966conv]

First things first!
Remove hoses from intake/water pump connection. Cut back to about 6 inches long, place baggie over end and twistie to contain fluid.
Remove the 4 nuts holding heater fan to firewall from engine bay side.
(Optional)Remove seat for more working room.
Get underneath and way up high against the cowl is one more bolt holding the heater box in. The glove box may or may not be in the way (Still connected to heater cables and plenum at this time)
Disconnect heater cables and fan wiring.
Disconnect defroster hoses from plenum.
Pull complete unit out watching hoses for leaking.

Rebuild, definately do seals and gaskets.

Reverse order.

 

[limey66]

...Reverse order.

You sound like a human Haynes manual...

 

[hungrymonkey]

use care when removing the clips off the of the heater box. The case will break.

also, do not do what I did and lose the metal bracket that goes by the flap. I looked for 3 months before giving up and buying a used one from the junkyard. Then I found the original one the next day.