Heater Core Replacement
Thread Starter
Racer
Joined: Jun 2005
Posts: 409
Likes: 13
From: Lavonia Georgia
Heater Core Replacement
I did the customary searches and found several threads on heater core replacement. Most said to replace from the inside, take dash apart....etc. However several folks said it could be done easily from the engine bay side. I've got the motor out so the engine bay thing sounded great. I got the blower motor/cover assembly off, cleaned out the old mouse nest that virtually covered the core and have gotten the clip off the bottom of the divider that seems to hold the core in place.
Problem is, the core still doesn't want to move. Is there something else holding it in there or am I just being too gentle. Since this one is coming out one way or the other, I don't mind getting violent with it if it's just crusty and needs persuasion. But on the other hand, I didn't want to start prying, beating and banging if there are other things I need to do before it will come out. Any ideas from you folks who have brought your core out from this side? Here's a pic of what I'm looking at.
Problem is, the core still doesn't want to move. Is there something else holding it in there or am I just being too gentle. Since this one is coming out one way or the other, I don't mind getting violent with it if it's just crusty and needs persuasion. But on the other hand, I didn't want to start prying, beating and banging if there are other things I need to do before it will come out. Any ideas from you folks who have brought your core out from this side? Here's a pic of what I'm looking at.
Team Owner
Joined: Aug 2000
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From: Massillon,Ohio USA
2020 C3 of the Year Finalist - Unmodified
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St. Jude Donor '08-'09-'10-'11-'12
...non-A/C '68-'79 Corvettes come out through the engine side of the firewall. Can't tell from your pic, but usually between the in & out water tubes there is a metal clip that just snaps in. Have changed a couple non-A/C cores, some have had this clip, one didn't. It is a tight fit and if it's been in there many, many years it may not come out very easily. Just be patient and keep working at it. 
Thread Starter
Racer
Joined: Jun 2005
Posts: 409
Likes: 13
From: Lavonia Georgia
Originally Posted by Paul Borowski
...non-A/C '68-'79 Corvettes come out through the engine side of the firewall. Can't tell from your pic, but usually between the in & out water tubes there is a metal clip that just snaps in. Have changed a couple non-A/C cores, some have had this clip, one didn't. It is a tight fit and if it's been in there many, many years it may not come out very easily. Just be patient and keep working at it.
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
I pretty sure the core is attached to the core box. There is a hump type bracket over the lines holding it in place. At least that is how mine was.
Take the box out from the inside. You are almost there anyway.
Jim
Take the box out from the inside. You are almost there anyway.
Jim
Racer
Joined: Jul 2003
Posts: 455
Likes: 0
From: Buffalo New York
On my '77 non a/c it came out on the firewall side...There was a clip and insulation holding the the core in on the left side and around the pipes...Even after I removed the clips it was a PITA to pull out...came out on about a 45 degree angle with a lot of pulling...
good luck
good luck
Thread Starter
Racer
Joined: Jun 2005
Posts: 409
Likes: 13
From: Lavonia Georgia
Originally Posted by 77BuffaloVet
On my '77 non a/c it came out on the firewall side...There was a clip and insulation holding the the core in on the left side and around the pipes...Even after I removed the clips it was a PITA to pull out...came out on about a 45 degree angle with a lot of pulling...
good luck
good luck
Now that I have all the nuts and the box off the engine side, should the inside housing push into the interior side for more access or is it being held in place by the ductwork?
I know JPD6000 said I should take it out from the inside, I'm almost there anyway. But I just got the interior back together and pulling the consoles, dash, radio and ductwork doesn't seem 'almost there' to me. It was an absolute PITA getting it all back together. If the dash has got to come down for this, I'll bypass the heater and core replacement will become a next winter project.
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From: In Dreams There Is Truth Ohio
Originally Posted by Hammerhead Fred
Gotta pull that figure 8 foam piece off to get to the retainer.
The clip is behind the foam.
I would take the heater core to your local rad shop and have it recored. Why? The new units don't fit very well and you may have problems getting the clips to fit. That's the problem I had when I replaced the heater core in my 68. Bought an AC Delco core, could not get the clips back in, went to the rad shop they switched tanks and voila, perfect fit.
Last edited by GDaina; Mar 7, 2006 at 09:46 AM.
Team Owner
Joined: Oct 2004
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From: Springfield MO
St. Jude Donor '07
I was just about to ask who makes the best heater cores. My 77's core isn't leaking, but I think I want to replace it during some major upcoming work, just to be safe. Anyone make an aluminum heater core? 
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Originally Posted by 68vertible
Was getting the new core back in there any easier? I cannot really see any clip between the I/O pipes and there is a very thick foam spacer around the pipes, sort of figure 8 shaped deal. I really don't have a problem hooking the back left side of the core and giving it a good pull, but I'd sure like to find that other clip first.
Now that I have all the nuts and the box off the engine side, should the inside housing push into the interior side for more access or is it being held in place by the ductwork?
I know JPD6000 said I should take it out from the inside, I'm almost there anyway. But I just got the interior back together and pulling the consoles, dash, radio and ductwork doesn't seem 'almost there' to me. It was an absolute PITA getting it all back together. If the dash has got to come down for this, I'll bypass the heater and core replacement will become a next winter project.
Now that I have all the nuts and the box off the engine side, should the inside housing push into the interior side for more access or is it being held in place by the ductwork?
I know JPD6000 said I should take it out from the inside, I'm almost there anyway. But I just got the interior back together and pulling the consoles, dash, radio and ductwork doesn't seem 'almost there' to me. It was an absolute PITA getting it all back together. If the dash has got to come down for this, I'll bypass the heater and core replacement will become a next winter project.
If you went from the inside I think all you would have to remove is the passengerside dash...
Jim