69 Heater Core w/AC Installation Question
Thread Starter
Burning Brakes
Joined: Feb 2016
Posts: 874
Likes: 115
From: Round Hill Virginia
69 Heater Core w/AC Installation Question
So, as I'm tearing my car down for restoration, I'm currently, among other things, rebuilding the AC box (I needed to replace the heater core). As I reassemble the interior box I've got a question on whether or not I need to use some of the black butyl tape where the heater core rest on the vent box?? It looks like it was used originally is why I ask...cushioning as well as sealing?? The seal replacement kit has some, plus I have some left over from a non AC box I did on my last car. This is the stuff that goes on the exterior box to seal to the firewall. The instructions that came with the kit sort of suck and the AIM isn't really a help either. There's actually only a few things in the kit that are applicable - I think. I'm hoping someone has some solid experience rebuilding or replacing heater cores that would have some advise and guidance for me on this. As much as a PIA this is to get the core out I don't want it to rub a hole in it or something, but also don't want to put something in there thats heat sensitive that really shouldn't be in there.
1967 Pedal Car Champion
Joined: Mar 2020
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From: US-PNW
I don't believe the butyl rubber should be on the inside surfaces of the box to firewall -- my a/c '72 did not have any. The butyl will keep the components from coming apart for core replacement later on and I don't see the need for such a complete seal like the engine side gets.
Completely agree on everything you said about the heater box seal kit. I think I only used 3 or 4 of the seals, the rest are in an "extras" box.
PS - make sure you test the heater core before you install and button it all back up. Brand new one leaked like a sieve!
Completely agree on everything you said about the heater box seal kit. I think I only used 3 or 4 of the seals, the rest are in an "extras" box.
PS - make sure you test the heater core before you install and button it all back up. Brand new one leaked like a sieve!
Last edited by barkingrats; Feb 11, 2021 at 10:46 PM.
Thread Starter
Burning Brakes
Joined: Feb 2016
Posts: 874
Likes: 115
From: Round Hill Virginia
The area Im talking about is between where the heater core makes contact with the assembly. There is a foam piece of foam from the kit that goes up front but there's nothing else. The old one seemed to have some of the same butyl type stuff there.
Last edited by nix1981; Feb 12, 2021 at 08:37 AM.
