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Heater Core Help Again - '72 Coupe

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Old Mar 1, 2009 | 01:09 PM
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Default Heater Core Help Again - '72 Coupe

It's me again. This time I'm stuck at the last step of removal. Getting the heater box assembly out of the car. I've removed three screws as shown in the pic. (The arrows point to the general location.) I should mention that my car has A/C which slightly complicates things.

The assembly wiggles but I can't figure out how to actually remove it. Seems hung up somewhere. The hoses are removed from under the car and I can wiggle it from there too. Have I missed a hidden screw or fastener somewhere? Thanks, as usual!



Last edited by alanbl; Mar 1, 2009 at 01:29 PM.
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Old Mar 1, 2009 | 01:17 PM
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dont know if you have this hope it helps.

http://www.corvettemagazine.com/comp...x-rebuild.html

Todd
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Old Mar 1, 2009 | 01:22 PM
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Did you get the one (with nut) on the firewall side/

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Old Mar 1, 2009 | 01:31 PM
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Originally Posted by cargo247
dont know if you have this hope it helps.

http://www.corvettemagazine.com/comp...x-rebuild.html

Todd
Thanks, Todd. I have the article and the rebuld kit from Zip. The article is for a later car so it's not exactly pertinent, but has helped. I also have the Corvette shop manual, Haynes, Chilton's and the AIM. None are really exact.
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Old Mar 1, 2009 | 01:32 PM
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Originally Posted by paul 74
Did you get the one (with nut) on the firewall side/

I didn't. I read about this "nut" but can't find it's location. I assumed that it's because my car has A/C. Can you be more specific about its location?
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Old Mar 1, 2009 | 01:38 PM
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Originally Posted by alanbl
I didn't. I read about this "nut" but can't find it's location. I assumed that it's because my car has A/C. Can you be more specific about its location?
its the nut and stud right in the middle of the pic above, it must come off.

mine is an 81 with ac and i still had tho nut in the same location. about.
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Old Mar 1, 2009 | 01:50 PM
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Right behind the passenger side valve cover. You can see the stud in this pic.


Last edited by Paul L; Mar 1, 2009 at 01:54 PM.
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Old Mar 1, 2009 | 04:58 PM
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Originally Posted by paul 74
Right behind the passenger side valve cover. You can see the stud in this pic.
Thanks, Paul. I see where the stud should be located. Here's a pic of the firewall behind the valve cover. I thought that I'd scrape the dirt off that lump and reveal the nut & stud. But noooooo! It's a rubber press fit type bullet. Or, is it a rubber cover over the nut & stud? I didn't want to just start cutting. It's in the right place and there's no other stud visible. Thoughts?

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Old Mar 1, 2009 | 05:09 PM
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Originally Posted by alanbl
Thanks, Paul. I see where the stud should be located. Here's a pic of the firewall behind the valve cover. I thought that I'd scrape the dirt off that lump and reveal the nut & stud. But noooooo! It's a rubber press fit type bullet. Or, is it a rubber cover over the nut & stud? I didn't want to just start cutting. It's in the right place and there's no other stud visible. Thoughts?
alanbl, I looked at my 72 and the stud is just below the wiper door vacuum actuator bracket.

cc
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Old Mar 1, 2009 | 05:14 PM
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I think if you just use an X-Acto knife or razor blade carefully by hand you will find a stud and nut underneath. Heck you might ruin $0.50 of a rubber cap.
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Old Mar 1, 2009 | 05:27 PM
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Originally Posted by paul 74
I think if you just use an X-Acto knife or razor blade carefully by hand you will find a stud and nut underneath. Heck you might ruin $0.50 of a rubber cap.
Is that US or CAN $.50? The US dollar ain't what it used to be! I just didn't want to go cutting off some rubber nub that would then release something important. I'll report back.
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Old Mar 1, 2009 | 05:33 PM
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Originally Posted by alanbl
Is that US or CAN $.50? The US dollar ain't what it used to be! I just didn't want to go cutting off some rubber nub that would then release something important. I'll report back.
alanbl, that rubber thing is probably one of the three firewall insulation retainers. It holds the top of the carpet and the insulation in place.

Your green arrows are pointing at two of them.

cc

Last edited by CCrane65; Mar 1, 2009 at 05:37 PM.
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Old Mar 1, 2009 | 05:42 PM
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Originally Posted by alanbl
Is that US or CAN $.50? The US dollar ain't what it used to be! I just didn't want to go cutting off some rubber nub that would then release something important. I'll report back.
A rubber nub releases nothing.
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Old Mar 1, 2009 | 05:45 PM
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Try moving your wiring harness a bit and see if it reveals the stud and nut. That rubber mass is too low to be it. It is below those rigid metal tubes in your picture above.

cc
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Old Mar 1, 2009 | 06:03 PM
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Clifford, Paul - Thanks for hanging in here with me!

This is eluding me. The rubber nub covered nothing and I can find no nut or stud on the firewall. I assume that this stud extends forward from the firewall towards the engine. The only nut and stud that is clearly visible is below. But this faces up. I removed the nut and the heater box did not change. I bet that I've identified where the stud is located on the box but cannot find it on the firewall!

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Old Mar 1, 2009 | 06:06 PM
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alanbl, too far toward the drivers side. Look further towards and below the vacuum bracket.

Follow those curved metal tubes and look below them near the vacuum actuator bracket.

Last edited by CCrane65; Mar 1, 2009 at 06:09 PM.
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Old Mar 1, 2009 | 06:16 PM
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Originally Posted by CCrane72
Try moving your wiring harness a bit and see if it reveals the stud and nut. That rubber mass is too low to be it. It is below those rigid metal tubes in your picture above.

cc
That's it! Clifford, I owe you several beers, Scotch or whatever is your beverage of choice! That little guy was well hidden and I could find it by braille. Then, once I moved the wiring, I could actually see the nut and get remove it. The heater box is now free and I just need to finagle it out.

Thanks, again!!!
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To Heater Core Help Again - '72 Coupe

Old Mar 1, 2009 | 06:23 PM
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Originally Posted by alanbl
That's it! Clifford, I owe you several beers, Scotch or whatever is your beverage of choice! That little guy was well hidden and I could find it by braille. Then, once I moved the wiring, I could actually see the nut and get remove it. The heater box is now free and I just need to finagle it out.

Thanks, again!!!
Anytime. Having just done this not long ago, it's still pretty fresh in my mind.

Did you buy a seal kit? I found that to be very necessary as mine had no seals at all. Was letting all sorts of hot air into the system from the engine compartment. With the seal kit installed it no longer leaks hot air into the vents.

Also, if you bought an aftermarket core, you will need to modify it some to make it fit correctly. If you have a radiator shop near by, I'd suggest having them repair your original. They are dated and all.

Good luck and if you need anything else just shout.

BTW I'll pm you my email address so you can reach me sooner. I don't always monitor the forum but I monitor email at all times.

cc
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Old Mar 1, 2009 | 06:39 PM
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glad you got it

Todd
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Old Mar 1, 2009 | 06:53 PM
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Glad you got things sorted out! Seal strips are available at Home Depot as door insulation.

Last edited by Paul L; Mar 1, 2009 at 07:00 PM.
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