heater core removal
Thread Starter
Instructor
Joined: Dec 2004
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From: Newmarket Ontario
heater core removal
I have a 1979 L48 with air conditioning and need to replace the heater core. I have gone through my two manuals and they are really no help. What is involved to replace. Is there some other maual that gives you a better advise.
Le Mans Master
Joined: Sep 2002
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From: Myrtle Beach SC
Originally Posted by canucbuck
I have a 1979 L48 with air conditioning and need to replace the heater core. I have gone through my two manuals and they are really no help. What is involved to replace. Is there some other maual that gives you a better advise.
Essentially, you are removing the glove box, A/C air ducts, gauge console (center upper cluster), lower console and a few other incidentals I don't recall. I removed the passenger seat for extra room to work and removed the carpet to avoid spilling coolant on my 38k mile original carpet.
A six pack added to the patience required to do the job and it really wasn't bad. The worst part was the install of the replacement heater core...it was not an exact replacement and the tubes were bent just enough to cause a headache. They are all made in Mexico or somewhere so the quality is not what it was when they were first produced. My suggestion use AC Delco...or Delphi who makes the Delco parts.
You must bench test your replacement unit before installing and no book will tell you that. My first unit leaked like a seave and had to return. To bench test, I filled with water than used my air compressor to pressureize...it either leaked or didn't.
Drop me a note if you decide to pursue.
Thread Starter
Instructor
Joined: Dec 2004
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From: Newmarket Ontario
Thanks for your help. I am starting this weekend to pull out everything.
Good time to replace some burned out bulbs, fix the clock and replace the old cassette stereo to something more updated. And you are right about testing the core before installing. But if you disconnect the hoses to the core which is under the car why would it leak when you remove it.
Good time to replace some burned out bulbs, fix the clock and replace the old cassette stereo to something more updated. And you are right about testing the core before installing. But if you disconnect the hoses to the core which is under the car why would it leak when you remove it.
Racer
Joined: Dec 2002
Posts: 421
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From: Long Grove, IL
Originally Posted by hunt4cleanair
... The worst part was the install of the replacement heater core...it was not an exact replacement and the tubes were bent just enough to cause a headache. They are all made in Mexico or somewhere so the quality is not what it was when they were first produced. My suggestion use AC Delco...or Delphi who makes the Delco parts...
Regards,
Jay
Le Mans Master
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From: Tuttle OK
Cruise-In VIII Veteran
Le Mans Master
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From: Myrtle Beach SC
Originally Posted by canucbuck
But if you disconnect the hoses to the core which is under the car why would it leak when you remove it.
2. You will remove it from the inside and you'll find manipulating it from the distribution box to remove it. In the process, its possible to spill.
There may be a way to remove it without spilling but I did not want to take a chance...I don't do it every day so my technique wasn't that precise.
Melting Slicks
Joined: May 1999
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From: Moon Township PA
Two things to add, prior to installing your replacement core, take it to your local radiator shop and have it pressure tested. More than a few new cores leak upon installation. Doing this job once is a PITA; doing it twice because the new core leaks is a major PITA. Second note, if your new heater core nipples are configured exactly like your old one, you can also have that same radiator shop, unsweat the ends from the original and put them on the new one. The previous owner did that to my 72 and now the installation looks and functions like the old core.
Gary
Gary
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Race Director
Joined: Feb 1999
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From: In Dreams There Is Truth Ohio
Originally Posted by griffths
Actually they all seem to come from the same factory whether the replacement heater core is from GM, Napa, Auto Zone, etc. I would suggest that you have your existing core rebuilt if it is a Harrison core.
Regards,
Jay
Regards,
Jay
Same problem with mine, took the core to the radiator shop and the recore was a perfect fit using my tanks.
Melting Slicks
Joined: May 1999
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From: Moon Township PA
Originally Posted by adam
What kind of leak did you have that the radiator shops were able to fix?
What's the difference between the original ends and the ends of the newer models?
What's the difference between the original ends and the ends of the newer models?
Gary
Race Director
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From: In Dreams There Is Truth Ohio
Originally Posted by adam
What kind of leak did you have that the radiator shops were able to fix?
Thread Starter
Instructor
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From: Newmarket Ontario
Making progress this weekend. Got the centre gauge console out.
Radios out and all the duct work. Problem-----------The maual says to drop the steering column, but with the bracket off you have to force it down and it springs back up????????? The manual also says to remove the speedo and tachometer gauges by "" Bring it out slightly forward and remove cable and light harness"". With mine with all the screws out it won"t budge at all, but did manage to break the speedo needle off. Can these be replaced or am I looking at a whole new speedometer gauge.
Radios out and all the duct work. Problem-----------The maual says to drop the steering column, but with the bracket off you have to force it down and it springs back up????????? The manual also says to remove the speedo and tachometer gauges by "" Bring it out slightly forward and remove cable and light harness"". With mine with all the screws out it won"t budge at all, but did manage to break the speedo needle off. Can these be replaced or am I looking at a whole new speedometer gauge.
Le Mans Master
Joined: Jan 2003
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From: Tuttle OK
Cruise-In VIII Veteran
Granted, it's probably easier to do so, but I've always been able to remove the speedo/tach assy without dropping the steering column. However, if you are going to drop it, there are also two nuts inside the firewall that need to be loosened before it will drop...
Good luck...
Good luck...
Le Mans Master
Joined: Sep 2002
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From: Myrtle Beach SC
Originally Posted by canucbuck
Making progress this weekend. Got the centre gauge console out.
Radios out and all the duct work. Problem-----------The maual says to drop the steering column, but with the bracket off you have to force it down and it springs back up????????? The manual also says to remove the speedo and tachometer gauges by "" Bring it out slightly forward and remove cable and light harness"". With mine with all the screws out it won"t budge at all, but did manage to break the speedo needle off. Can these be replaced or am I looking at a whole new speedometer gauge.
Radios out and all the duct work. Problem-----------The maual says to drop the steering column, but with the bracket off you have to force it down and it springs back up????????? The manual also says to remove the speedo and tachometer gauges by "" Bring it out slightly forward and remove cable and light harness"". With mine with all the screws out it won"t budge at all, but did manage to break the speedo needle off. Can these be replaced or am I looking at a whole new speedometer gauge.
Le Mans Master
Joined: Jan 2003
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From: Tuttle OK
Cruise-In VIII Veteran
Originally Posted by hunt4cleanair
You shouldn't have to drop the steering column or remove tach/speedo gauges...remember now that manual still may be suggesting pre-78 type interiors. I did not have to do either in my 78 and your 79 is identical to 78.
I did mine on the '80 and can't imagine trying to get to all that stuff with the dash in.
Just curious...
Thread Starter
Instructor
Joined: Dec 2004
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From: Newmarket Ontario
Actually the dash was the easy to remove. There where six screws total and alot of patience to take out. The dash is really flimsy with nothing attached to it. Btw I bought a used speedometer (after breaking the needle off mine) from an auto wreckers for $50.00 with the tack. Tonight I attempt to go after the core itself.
Le Mans Master
Joined: Sep 2002
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From: Myrtle Beach SC
Originally Posted by Avette4me
Hey Hunt - not saying it can't be done, but how did you do your core (with A/C) without removing the dash (assuming that the '78 has a one piece)?
I did mine on the '80 and can't imagine trying to get to all that stuff with the dash in.
I did mine on the '80 and can't imagine trying to get to all that stuff with the dash in.
Le Mans Master
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From: Tuttle OK
Cruise-In VIII Veteran
Originally Posted by hunt4cleanair
Your assumption is correct...one piece. Just loosened everything up (the dash) and manuvered it out. I'm not saying it wasn't a bitch though but removing dash seemed worser option of the two.