Author Topic: Heater Core Box Restoration  (Read 228 times)

Maxthe222

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Heater Core Box Restoration
« on: September 20, 2019, 03:22:51 AM »
Ok, well a little sub-project while i'm getting both cars back on the road.

I couldn't find any good threads about disassembling or putting the heater box thingy under the dash back together, so I thought I might list it seperately. It's moreseo to remember how I took it apart so I can put it back together. 

Since my Y84 is currently off the road to make everything in the interior nice (and heaven forbid acutually get the electronics working since nothing has been plugged in for 20 years) I decided to pull apart the Y84 heater box first. I could only get it half off, (might have even broke it a bit) because the heater core would just not come off the firewall, and it was never plugged into the engine or anything since I got it, so the "door" part that has the two holes that is infront of the firewall had to come off seperately (it's still on the car lol I srsly can't get it off see for yourself lol)



It's actually in pretty reasonable shape, the one off the Fire Am is much worse. I expected it to be a lot dirtier and rusty, but it's complete and it looks like it all works and moves as it should. The core looks new, so I'd assume it's been taken apart before, but shock horror all the correct screws are where they should be which is bizzare since the guy who put this car back together must have thrown them all out when he put it back togehter. My only concern is there is a big chunk missing from the bottom part, including one of the bolt holes for mounting it to the firewall. Is this something I should be concerned about? Is the air going to leak out of it or will the A/C quailty deteriorate? It's the only real fault with the box, i'd hate to have to get another one. I don't think it's a major problem, but I could be very wrong.



I disasembled the box, took the large metal plate with the vent off first by removing the three small clips, the spring holding onto the valve on the thing end, and a handful of 1/4 bolts. I then noticed it was stuck, and then saw that the valve was connected to the rusty door on the other side by a single screw along the metal beam coming off the valve. I had to remove the small rubber grommet that is where the vaccum hose comes out, and I could fit a socket onto it to remove it.



Next, I took off the wheezy-boi off the thin end of the casing with a 3/8 socket and got the nut-thingies off. To seperate the wheezy boy from the door, I got some needle nose pilers, and pushed this black clip together to free the door.



Now that the door was free, I could get a nice whiff of that nice, one owner barn find low miles rust. The foam padding (or whatever it was) is totally deteriorated. The staples were good tho! Might have to take them off and re-install them when I get new material. Might just dunk in acid, sanding it might not be enough. Question 2: What is this material anyway? Can I just put any foam there?



Next, I took apart the two mechanisims on the top. The large flat weridly shaped piece just came off with the three screws, I needed to remove that piece before the heater core door came off. The other, I couldn't really do much with because it appears that it is fixed on there or welded on, I removed the screws, but that's as far as it seems to come off. I'd like to fully remove them to clean them properly, but that may not be an option it would seem. I've heard the "soak in evaporust" thing several times, but evaporust in australia is $100 for 5L. To fill a tub with enough of the stuff to properly soak those parts still attached to the casing may be pretty difficult. I might be able to just sneak some sandpaper on there and work on it like that, but might not do the job properly. For all the pieces that are meant to be bare metal from factory, I found this great prime and paint clear spray paint that looks really good when applied to bare metal pieces, so after they're cleaned I plan on coating them with that. I have a feeling that that may be the best way to fix the door as well, just sandpapering it and then coating it with that clear P&P.



After everything was out, I took it out in the yard with the two big door/hinge pieces still attached (since I couldn't see a safe way to remove them) and just hosed it out to get allllllll the gunk and dirty and dust out, and lemme tell ya it had built up a lot of goey stuff in there. Hose got almost everything out, but went in with a green/yellow sponge to scrub out any of the stains or gunk still left over, and it actually came out really clean.




So now it's just a matter of cleaning all the pieces up nice and shiny, getting that thing off the firewall, and slap it all back together!

Here's the big concerns tho:
1. Is the crack in the casing something to worry about
2. What is this foam do I need to put on there, and where are all the positions that I put the foam on?
3. Can I remove those little mechanisims and doors off the casing?

1979 T/A Y84 WS6
1979 F/A W72 WS6
1971 Formula 400 4-Speed

Maxthe222

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Re: Heater Core Box Restoration
« Reply #1 on: September 25, 2019, 02:39:09 AM »
Hmmmm, thought it would look better but it was more of a test run to see how it'd go, since this box has cracks and boofs anyway I wasn't expecting it to look 100% imacculent, but I think this is a good improvement. Has a lot more scratches on it when it's cleaned! It had a lot of overspray marks all over it from when the previous owner must have touched up the dash or repainted it. Gave them a firm wipedown with some multi-purpose paint thinner and the overspray came off pretty nicely.



The top mechanisim arms cleaned up nicely. Took a very weird angle and tiny container to just submerge the metal components into a rust remover.



Gave them a nice thick coat of clear primer to hopefully keep them sealed. Now to put the rest back together

1979 T/A Y84 WS6
1979 F/A W72 WS6
1971 Formula 400 4-Speed

Maxthe222

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Re: Heater Core Box Restoration
« Reply #2 on: October 08, 2019, 12:31:36 AM »
All done, back together and all the foam seals were replaced, however, the foam piece underneath the hinge of the door flap on the front was a tight squeeze. I double side taped all the seals on, cut them to fit, and just firmly attached them, but for the one underneath the door, after testing the fit of the foam, I found that it just got stuck underneath the hinge and didn't need the tape. I put a little bit underneath anyway, but even with vigorous movements from the door, I couldn't get it lose, so let's just pretend it'll stay there until next time. I taped off all the plastic around what metal bits there was and just sprayed clear paint and prime over them a dozen or so times. Looks terrible after a few days, but didn't just wanna paint it black or leave it bare again. Some spots actually look good, but some have some rust that came through underneath. Oh well, deal with it again in another 40 years, but for now I'll keep them lubricated with WD-40 that'll give the added bonus of WD-40 scented A/C air.





In terms of materials used, I just used generic soft cell foam I got from a foam/rubber/plastic store. Wasn't anything special, and was very cheap for 40cm^2 of material. I got extra so I could make the gasket type foam seal for the A/C duct that attaches to this heater box. I went with 3M double sided mounting tape just incase some generic clear super thin officeworks tape's adhesive deteriorated with the constant airflow or hot air melting it.
« Last Edit: October 08, 2019, 12:35:52 AM by Maxthe222 »
1979 T/A Y84 WS6
1979 F/A W72 WS6
1971 Formula 400 4-Speed

Maxthe222

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Re: Heater Core Box Restoration
« Reply #3 on: October 08, 2019, 12:39:37 AM »
Another thing I had to toy with was the door adjustment. If you left it in the default position, the door would not be entirely closed. I noticed that on the box I pulled from the Fire Am that it had different markings on it, so either the '78 box was different, or a different manufacure made that box. It had a different moulding around the door area, and it closed and sealed flush in the default postion. After adjusting the screw postion on the long arm ontop of the, I was able to have the door slightly push against the opening to ensure it was properly closed. I'm not sure if that's the way it is supposed to be, but it didn't make sense to have the door open just a cm or two as air would still come in. Maybe some vaccum in the valves closed it once the car turned on?
1979 T/A Y84 WS6
1979 F/A W72 WS6
1971 Formula 400 4-Speed

roadking77

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Re: Heater Core Box Restoration
« Reply #4 on: October 08, 2019, 06:26:15 AM »
Turned out nice.
Finished!
77 T/A - I will Call this one DONE!
79 TATA 4sp-Next Project?
79 TATA - Lost to Fire!
86 Grand Prix - Sold
85 T/A - Sold
85 Fiero - Sold
82 Firebird - Sold
'38-CZ 250
'39-BSA Gold Star
'49-Triumph 350
'52-Ariel Red Hunter
'66-BSA Lightning
'01-HD RoadKing

Re: Heater Core Box Restoration
« Reply #4 on: October 08, 2019, 06:26:15 AM »

nigel

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Re: Heater Core Box Restoration
« Reply #5 on: October 08, 2019, 11:14:45 AM »
Nice one, that's my winter project this year although I have to repair a hole in the heater box as I'm going to reinstall the A/C which was removed by the previous owner.

Re: Heater Core Box Restoration
« Reply #5 on: October 08, 2019, 11:14:45 AM »
You can help support TAC!