JackJack56Olds

Does anyone know if I remove the heater core from under the dash or have to take the big heater box off the firewall under the hood? Thanks.

Tedd Thompson

Heater core comes out from under the dash, only the heater hoses are addressed from the firewall side.....Tedd

redoldsman

Please keep us posted. I am going to have to pull the one out of my 54 and am wondering how bad it is going to be.

Tedd Thompson

Other than laying upside down for a hour or so the problems that arise that the manual doesn't address is the mastic sealer that holds the shroud to the dash wall, it is sometimes a bear to separate this peace so you can free the heater core. A heat gun can be your friend at this point....Tedd

twintracks

I don't know how different a '56 is from a '55, but I just did the job on a '55 Holiday.
The core comes out from the inside as stated. However, in the '55, I had to also pull the fan motor, and part of the shroud from under the hood to get to a few screws that kept the core in place. If it does not come out easily, keep digging for more screws.
You might have to remove the glove box liner, and speaker assembly to get the inside ductwork out. Mine is factory air, so there was lots more to remove for me.
My core was leaking badly, and I also found a huge rodent's nest crammed up against the outside of the core. They were coming in through the rubber drain tube. It never would have worked, had I tried it.

Tedd Thompson

I wonder if something is different in a AC car? I didn't remove anything off my firewall and the only hidden screws were under the rubber gasket on the shroud. Its been a few years ago when I did this but the air box blower assembly still has new undisturbed paint on all the screws so I know it hasn't been off since the restoration.....Just curious...Tedd

twintracks

Mine has a shroud screwed to the front, that has a second air deflector that is screwed to the firewall components. I had to reach in through the opening where the fan & part of the housing was removed to get to the screws with a nut driver. I'll take some photos of my firewall. It's all original with firewall markings. It must be a different set-up on the AC cars. It's all reassembled now, and throwing heat. Since it's a CA, NM car, I doubt the heat has been functioning since about 1960...

JackJack56Olds

I've AC and worse yet my uncle started tearing into it before I took ownership so i'm a little lost at what goes where. The box under the dash is hanging there but not out of the way and there are a few screws missing to the box in the engine bay. I plan on taking the box off the firewall under the dash and in the engine bay so I guess I'll see what I'm up against there and hopefully snap some pictures.

JackJack56Olds

I looked at the manual last night and just glanced at the car. The manual sure leaves a lot guess work. I guess its probably just best to get on in there and work at it. Here are some pics.

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JackJack56Olds

I pulled the heater box off. Found some nice debris and a toy car. After getting the box off I tried getting the core out from under the dash but it wasn't budging. I wasn't sure if there were screws holding it in so I backed out the two screws you see in the picture from the engine side of the deflector. Those screws to that deflector actually don't need to come out. They don't go into the heater core so I screwed them back in. Then I pushed the core from the engine side and it broke free towards the inside of the car pretty easily. If you don't have the heater box off in the engine bay then I can see how it might be tough to pull the core out from under the dash. Things get seized after so many years even if its a foam seal. The only thing that was holding it in there was the foam seal around the core. From there I was able to get it loose all the way and pull it out under the cover under the dash. it seems the foam seal was originally glued to the heater box and over time seized itself all the way around where it meets up with the firewall.
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JackJack56Olds

I dropped the heater core off at the radiator shop. They said it was an old style of core and that you can't really repair after these many years. Apparently all the white spots eat away at it and it was crumbly. He said what he can do is get the same size square core and remove the tanks off the old one and install on the new core then put it back in the black frame. He is supposed to call me with details if this can be done.

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twintracks

Yep, That small deflector is what I tried to describe above.
I'm glad you finally got it. I can now confirm that '55 and '56 are the same inside.
My recore was about $280.00. It was rebuilt as you describe with a new core, and my tanks. Great working heat on an AZ car that now resides in WI. It's a good thing.


Jerry

JackJack56Olds

I got my heater core back. The guy ended up finding a Ford Truck heater core with the same width but different length. He cut it and soldered on the old tanks from the original. $210 + Tax later I have a heater core. We'll see how it does.


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JackJack56Olds

I started laying out the gasket last night. I picked up the weatherseal from Lowes. Should work ok.
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The original felt that was held in by clamping two pieces of metal to make up the blend door was pretty rough so I took it out and found this new felt to use. This isn't the most beautiful end result but it should work. Basically the felt helps seal the blend door on both sides. I started by attaching it with hot glue but figured that would just deteriorate or become loose over time so I clamped it down with brackets on front and back for both sides. Its functional and hidden so should be fine.
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JackJack56Olds

Does anyone have a picture of an original style screw that holds the heater box to the firewall under the dash? I know its probably asking for a lot considering its a 60 year old vehicle but trying to keep things legit. I received the car with the box off the firewall and missing all screws. Thanks.

WHIPOLDS

Does this help?


Let me know if you need further pictures.


Rick

JackJack56Olds

The picture is kind of hard to see. is this what it looks like? http://www.screwboss.com/Templates/p...ng-screw-1.jpg

WHIPOLDS

That's what they look like.
Rick

JackJack56Olds

Thanks Rick.

JackJack56Olds

Almost completed. I didn't use the gasket that I made below because it was a little too thick and didn't seal the blower that well. I used the same strip caulk I used to join the other pieces. This is the product from Eastwood. http://www.eastwood.com/ew-flexible-...-bk-2-lbs.html

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z11375ss

I don't know why you didn't immediately remove the fender.

Just kidding. i got a small flame job for removing my fender when i did the one on mine. You've done a really nice job on that 'ol girl. It's worth it though.

JackJack56Olds

hey, whatever gets the job done right!

JackJack56Olds

Complete.
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Tedd Thompson

Just curious, did you check your blower motor for function while you had it out, It looks like you replaced the wiring....Tedd

classicmuscle442

Not sure if you got heater box back together already, but a great gasket material is cork tape. Its black, somewhat sticky, waterproof about 3 1/2" wide and is used in HVAC work. We use it to seal a/c coil box to furnace cabinet.

JackJack56Olds

yes I checked the blower motor and it spun up nicely. I used some of that East wood rope caulk to seal the box seemed very similar to the original material.

JackJack56Olds

oh and I didn't replace the wiring that was just after I cleaned it up.

redoldsman

I pulled my heater core out yesterday. Not as bad as I expected but not fun. That black tar like stuff that seals it is a bear to break lose. My core has no evidence of leaking and the paint on it is still good. I put water in it and it did not leak. Of course there was not pressure. I will still take it to a shop and have it tested. I replaced the Ranco valve and it did appear to have leaked. The heater was disconnected and this had been a California car so no telling how many years since the heater worked.

JackJack56Olds

I'm telling ya, if it wasn't for me taking the whole heater core box off the firewall on the engine side I would have pried forever. I just pushed it from the engine side and came loose easy. is it the original one? I'm curious if repairs were needed what the rad shop would tell you; if they could fix it or would have to do what I had done and go with a new style and cut it to size.

redoldsman

It looks to be in good shape. I won't take any chances though.

Tedd Thompson

There is nothing special about being a California car that makes it exempt from weather, we have all the nastiness that the rest of the world has. I use my heater- defroster every time I take it out of the garage this time of the year, wipers too. ...Tedd

redoldsman

Thanks for correcting my false assumption on that Tedd. I was just guessing that somebody in Boston might use their heater more than somebody in California. Maybe not.