Leaky heater core -Next issue

[Print Dad 58]

Hello all,

Well I'm back with the latest issue. Today, when i was driving, the windshield started to fog. I put on the defroster and lots of little rust particles blew up.

The windshield, stayed about the same. It didn't get real bad but didn't get any better.

I looked under the dash and see no signs of wetness. I then checked the radiator and it looked full.

I am thinking the heater core has developed a leak but is it possible it is due to the fact that the car sat for 23 years?

 

Any links as to how to replace the core. I think I can handle this, but I would sure appreciate any ideas. I do know, I could bypass the core for now, but my wife gets cold.

 

So I need advice and opinions on what I should do. Perhaps I should just pull the core and replace it. The money just keeps finding away to get spent LOL

My wife was excited we got the car running and she was even talking of saving a bit for a new set of tires. She likes the raised whites we had that dry rotted. I guess this goes with the hobby.

 

Thanks......... Print Dad

[foothilltom 33]

Hey Jim, I actually replaced the heater core in my boy's car when we had it all tore apart. It wasn't too terribly awful but I had the entire dash out at the time, so I guess that's the worst part you'll be facing if you do wind up replacing it.

 

I'm thinking you could do this with just the dash pad out and the glove box perhaps, but I might be misremembering.

 

Anywho, I can't think of where else your moisture would be coming from. Was it raining? (Wondering if you have a leak in the cowl). The hoses themselves could have just cracked but it'll be hard to determine that easily.

 

Just shooting from the hip here, but hopefully others will have some actual useful info for ye.

 

Tom

[Print Dad 58]

Hello Tom,

Thanks for the reply. I was looking this project up and it may involve removing the dash pad, instrument cluster, Dropping the steering wheel and a whole lot of stuff. I really hope not especially where I stink at wires.

 

There was no rain and there isn't moisture under the heater box that I see. I am hoping

it isn't the core but I think perhaps I messed things up a bit when I worked on the intake. Perhaps a little movement on the core tube was all it took. I'm just starting to check things out.

 

Thanks again for the post. I hope others will have some good news like i only have to remove the pad and glove box but we shall see. Print DAd........ Jim

[rmarks 20]

Replacing the heater core is a royal PIA. When I did mine, I had to remove the whole dash. Others may have some tricks/tips and you may be able to get away with removing everything on the passenger side and leave the metal dash in place, but I wasn't able to. I have A/C (not woking) and the A/C evaporator coil is in the box too, so if you have A/C, recommend you chnage that too while you in there. Good luck.

[69RestoRod 10]

Print dad, AC or non Ac car? Removing the dash isn't that hard. After doing it half a dozen times you'll have it down to under fifteen minutes. If it's a non AC it's easy to cut the hoses, remove the bolts and nuts and drop the heater core box. If it's an AC car it's a bigger pain cause everything is squeezed into the dash. Can easily be done in a weekend, assuming you don't get a case of "While I'm at it". Heater cores aren't to pricey either. Check out RockAuto.com if you haven't already.

[Print Dad 58]

Print dad, AC or non Ac car? Removing the dash isn't that hard. After doing it half a dozen times you'll have it down to under fifteen minutes. If it's a non AC it's easy to cut the hoses, remove the bolts and nuts and drop the heater core box. If it's an AC car it's a bigger pain cause everything is squeezed into the dash. Can easily be done in a weekend, assuming you don't get a case of "While I'm at it". Heater cores aren't to pricey either. Check out RockAuto.com if you haven't already.

 

Hello All,

I should have mentioned the car is a 70 Mach with no air.

I read in several places I gotta drop the steering wheel, remove the instrument cluster, pad, pass side clock. It seems like evrything.

I ws hoping it would be a little easier.

I was hoping a bit easier. I am afraid of touching the instrument cluster.

 

Thanks......... Print Dad

[jmlay 80]

You do not need to remove the instrument cluster. Remove the assembly & you should have very little trouble putting it back together if you lable all wires & disconnect as few as possible.

 

Mike

[Print Dad 58]

Hello jmlay,

When you say remove the assembly do you mean the instrument assembly.

Sorry but I am a bit confused. I read in an old Chilton's that I could remove the pad, clock, radio and then disconnect the cables for the heater and then unbolt the box and she should pull forward.

On the internet I found a post that said it is a lot of work and eveything must come out. I am a bit confused. They mention pulling the steering wheel, dropping the ignition switch and basically taking everything out.

 

I am a total dummy on wires and feel for sure I will break things.

If i must do a lot of removal I must but I am still a bit uncertain.

 

This is where I looked

http://1970mgr.org/_HeatBoxRemove.htm

 

Any thoughts,,,,pros/cons

 

Thanks as always Print Dad

[foothilltom 33]

Hey Jim, I don't want to give you confusing messages, but from everything I recall, you could remove the dash pad and "loosen" the entire dash assembly (leaving the instruments all in place and all wires connected) to facilitate the removal of the core.

 

My recollection is you could get to the heater core with some gymnastics even with the dash in place, but I think it would be much easier if you just removed the bolts that fasten the dash to the firewall and just move it a little bit out of the way.

 

In short, I don't think you'll need to remove any wiring harnesses if you don't pull too far on the dash itself.

 

My $.02,

Tom

[ashleesmach1 28]

Hello again, I suggest you get a friend that has done this before because it is a bear to do. My best friend, who has done it before, and I took better part of two days to replace the one in my car. Every winter I send him a gift card for helping me do it. Take your time and make sure your prepared with everything you need. I also had to rebuild the box it was sitting in too. Good luck you will thank yourself later.

[jmlay 80]

I was talking about the complete lower dash, with the clock & gauges still in place. Obviously the pad would need to be removed first along with the column. The wire harness is attached to the lower dash as well. If you were not going to completely remove it just remove the bolts from the lower dash & pull it to the rear, supporting it from below. In reality I think it would be very difficult to mix up the wiring.

 

Hello jmlay,

When you say remove the assembly do you mean the instrument assembly.

Sorry but I am a bit confused. I read in an old Chilton's that I could remove the pad, clock, radio and then disconnect the cables for the heater and then unbolt the box and she should pull forward.

On the internet I found a post that said it is a lot of work and eveything must come out. I am a bit confused. They mention pulling the steering wheel, dropping the ignition switch and basically taking everything out.

 

I am a total dummy on wires and feel for sure I will break things.

If i must do a lot of removal I must but I am still a bit uncertain.

 

This is where I looked

http://1970mgr.org/_HeatBoxRemove.htm

 

Any thoughts,,,,pros/cons

 

Thanks as always Print Dad

[69RestoRod 10]

I'm seeing some mixed messages. I don't see why the steering column would need to be moved in a non AC car. In an a/c car ducts run over the column to reach the driver's side vent, so things would need to come lose to disconnect them without trashing them.

 

To remove the heater core you need to remove the dashpad. Remove the radio. Remove the plastic pieces on each lower corner of the dash and on each side of the radio. In the radio's hole there are 2 screws that go straight up into the pad. There are a screw under each plastic trim piece on the corner. Remove the 3 screws on the top on the instrument panel that go into the dash pad. Remove the lower screws on passenger side clock panel. The clock panel comes off with the dashpad so you'll have to reach behind and unhook the wire once everything is lose. If you have a glovebox light it will be two sets of wires. Remove the three screws against the windshield. I think I've listed them all, 13 by my recollection. The dashpad should come off with the clock panel attached and the instrument panel still mounted to the dash. There's a chance if the windshield was replaced there may be some black sealer holding the dash back. You'll see the heater core box and the bolts to remove it should be obvious.

When you put it all back together make sure your VIN plate doesn't get tucked under the pad.

Edited October 13, 2009 by 69RestoRod

[jmlay 80]

Considering the column is bolted to the firewall & the dash dictates it will need to be disconnected on one end or the other.

[69RestoRod 10]

Considering the column is bolted to the firewall & the dash dictates it will need to be disconnected on one end or the other.

 

 

The lower half of the dash doesn't need to be unbolted. I changed my non ac heater core out and then later converted it to factory ac without ever unbolting the lower dash. My lower dash wasn't touched until I stripped the car bare to start on rust repairs. Just have to pay attention to how you maneuver the box in and out. Not trying to start a debate, this is just what my experience had been.

 

Just trying to save him a few steps and prevent the possibilities of unwanted rattles.

[LoneWolf2U 136]

Ok, you made me look it up because it has been so long doing it.

 

From the Ford Shop manual 34-03-30

 

1.disconnect battery ground cable

2. drain cooling system.

3.remove dash pad

4.remove glove compartment liner and door.

5. remove the air distribution duct from heater

6. disconnect the control cables from the heater assy.

7 disconnect the wires from the blower motor resistor.

8. remove the right courtesy light located on the underside of the panel if so equipped.

9. remove the heater support to dash panel attaching screw.

10. disconnect the vac hoses and remove the power vent air duct.

11. remove the blower motor ground wire in the eng compartment.

12. disconnect the heater hoses from the heater at the dash panel.

13. working in the eng compartment remove the 5 heater assy retaining nuts.

14. remove remove the insterment panel to cowl attaching screws.

15. remove the insterment panel right side brace.

16. pull the heater assy and the right side of the insterment panel rearward and remove the heater assy.

 

Install in reverse order. :biggrin:

[LoneWolf2U 136]

Hey PrintDad........ this was for you!

[Print Dad 58]

Hello Mach1Rider and others,

First Thanks a real lot. This is a tuff job, kinda tougher than it should be I think.

 

Mach1Rider, I did exactly those steps and perhaps a little more.

 

Where she stands now is I split the case in the car, and pulled the old core.

I gotta admit the old core looked pretty good but I would never take a chance so it is full speed ahead.

 

I looked at the damn unit and it should come out.There is nothing holding it - - no vac lines - - no braces etc.

 

I had to clean up the door assembly inside as it was rusted pretty good.

I installed new gaskets. My next try is to attempt removal once more and if not, I 'm

gonna rebuild the box in the car. I really would like to pull the unit as I think it will be easier to attach the heater hoses and box clips.

 

If I can't get the box to come out, does anyone have any tricks how I can get the 2 clips on the pass side back on? It is real close to the edge of the car.

 

 

I know the box should drop, but it is loose and wiggles and even pulls inward but won't drop. I re-checked all the bolts, clips, door arm cable etc. The hoses are off as well. Damn if i can tell where she is hagning.

 

So any ideas on the 2 side clips?

 

I appreciate all the comments and ideas. I am close but would like to do this right which is to pull the box and rebuild outside.

 

Thanks......... Jim

[69RestoRod 10]

I've got my ac box sitting on a shelf in the garage and have a note to try and snap some photos of it tomorrow. Maybe there's something you're not seeing. I wish I could be of better help but it's been a few years since I last took it out.

[Print Dad 58]

Hello 69RestoRod and the other responders,

Just got a foot of snow so the car is on hold for a day or two.

 

RestoRod, I appreciate the offer.

 

Mach1Rider, - I know you gotta be saying this guy is nuts. He must have missed something. I triple checked. All the bolts off the firewall, cables unhooked, hoses off, 1 bolt on inside bracket, wires disconnected, light out, glovebox out, Everything.

 

I am going to try once ,more probably Monday and see if I can pull the box. I really would like to get the box out and assemble outside.

 

Thanks for helping to so many great great people. You guys are very patient and kind Print dad - - Jim

[Print Dad 58]

Hello All,

Making great progress. The core is in, the box is back and I am almost finished.

 

So I wanted to update the forum as to what I did.

 

I split the case/box inside the car. After pulling the case apart, I was able to

pull it forward more. So once apart, there were some rust issues inside the

box. There is a metal frame that holds the flapper door. it had quite a bit of rust

so I took care of that.

 

While I am working under the dash, I am cleaning, painting etc. so the progress is slow.

 

I also wanted to mention, I believe I could have done this job (core replace) by just splitting the case. To change the fresh-air intake gasket, I needed to lower the box on the pass side.

 

All in all, things are almost there. I reall appreciate all the help. This was a job, I was not to anxious to do, but now that it is almost over I am excited.

 

Thanks to a great great bunch of people........... Print Dad