1975 heater core replacement with a/c
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Joined: Mar 2007
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From: King Of Prussia Pa
1975 heater core replacement with a/c
Has anyone actually replaced the heater core on a 75 with a/c? I see some posts on here but none are actually for a 75, unless I'm missing something. One of my winter projects is to replace my heater core and all the weatherstipping and seals, etc. Could really use some pics etc. Yes I know what I'm getting into, but it has to be done and also do some work on the a/c vents and ducts.
Le Mans Master
Joined: Jul 2006
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From: charlotte north carolina
the outer air box must be loosened because the four studs hold the inner and outer boxes together, then remove the right side dash and the inner box. you should be able to leave the control cables in place at the console and disconnect them at the inner box. the center air ducts can also be left in place. pull the right seat out to make this pita job easier. there was an extensive post on this with good pics about a year ago. a straightforward job, just a lot of contourting.
Race Director
Joined: Oct 2000
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From: Shamong, NJ
Do a search of the forum, there have been many photos and instructions posted in the past. It doesn't make any difference what year you have, the job is the same on ALL 68-82 Corvettes with air. The only variation to the job is that on 68-77's you pull the right side of the dash and on the 78-82's, you pull glove box out of the dash or the whole dash.
Race Director
Joined: Oct 2000
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From: Shamong, NJ
You don't need to pull the motor to replace the heater core. It comes out from the interior side, the outer box doesn't need to be removed, thankfully!
Le Mans Master
Joined: Dec 2003
Posts: 5,727
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From: Fremont CA
This is about THE WORST job to perform on a C3 Vette. Make sure to reconnect oil line to center guage stack when buttoning up the dash (DON'T ASK! why I'm telling you this, it is too painful to tell the story even today over 15 years after the "great oil down".)
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Race Director
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From: Shamong, NJ
Oh, and the oil line isn't an issue on a 75, they used an electric oil gauge.
Team Owner
Joined: Aug 1999
Posts: 30,995
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From: Ontario
Do a search of the forum, there have been many photos and instructions posted in the past. It doesn't make any difference what year you have, the job is the same on ALL 68-82 Corvettes with air. The only variation to the job is that on 68-77's you pull the right side of the dash and on the 78-82's, you pull glove box out of the dash or the whole dash.
Drifting
Joined: May 2005
Posts: 1,629
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From: Somers CT
I did my 75 w/AC a couple of years ago. I didn't think it was actually too bad, I knew I had to pull the dash and ducting so I prepared myself mentally a little I guess. As stated above, it comes out from the inside and there's some fasteners under the hood to loosen.
I think I have some more detail pics I can post later.
I think I have some more detail pics I can post later.
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
I did my 75 w/AC a couple of years ago. I didn't think it was actually too bad, I knew I had to pull the dash and ducting so I prepared myself mentally a little I guess. As stated above, it comes out from the inside and there's some fasteners under the hood to loosen.
I think I have some more detail pics I can post later.
I think I have some more detail pics I can post later.
Thread Starter
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Joined: Mar 2007
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From: King Of Prussia Pa
Thanks everybody for all the input. For some reason I can't grab anybodys post and quote it, not sure what's going on there. But I will definately check all the past posts and use all the info I got from you guys
Drifting
Joined: May 2005
Posts: 1,629
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From: Somers CT
Here's some photos of the surgery.............Basically what Paul showed you above. There are several vacuum hoses hooked to various places, MAKE SURE YOU LABEL THEM. The red circles were to show someone where the shutoffs were. It looks ugly but it's not that bad a job, just take your time and think about what your doing.
Get these seals for the pipes where they exit under the hood, if you don't the exhaust fumes will get intoi the cabin.
Make sure the seal on this piece if good, it's a source of hot air getting into the duct if it's bad.
Also the seal on the flapper on this piece:
Get these seals for the pipes where they exit under the hood, if you don't the exhaust fumes will get intoi the cabin.
Make sure the seal on this piece if good, it's a source of hot air getting into the duct if it's bad.
Also the seal on the flapper on this piece:
Le Mans Master
Joined: Jan 2003
Posts: 6,575
Likes: 1
From: Tuttle OK
Cruise-In VIII Veteran
