Heater Core-Sometimes You Win...
Thread Starter
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
Heater Core-Sometimes You Win...
...and sometimes you lose. Five years ago my heater core (with A/C) went bad. So I bought the super-duper, AC Delco, Made in USA version so I would not have to repeat that difficult job.
When I was coming home from a show yesterday-Sunday (I posted pics here) I noticed a "sweet" smell at red lights and I lost some coolant from the overflow tank. This was with my shut-off ball valve in the 5/8" hose on "Off". I didn't think too much of it but today I decided to do a test. Ran the car up to 180*F in the garage with the ball valve "Open". Yes, you guessed it the heater core was bad. With heat controls on, mist was flowing through vents and fogging up the windshield and the passenger side carpets got a green bath. That is all cleaned up now and I face that nasty job ahead. I will just use the waterpump to intake bypass method to keep driving this season.
But I must say that I am pretty disappointed with the AC Delco product. Perhaps Chinese or Canadian (Spectra Premium) might be better. I really do not know what to order at this point. It's a pig-in-a-poke when it comes to quality. I may just go NAPA and hope for the best. I am frustrated.
When I was coming home from a show yesterday-Sunday (I posted pics here) I noticed a "sweet" smell at red lights and I lost some coolant from the overflow tank. This was with my shut-off ball valve in the 5/8" hose on "Off". I didn't think too much of it but today I decided to do a test. Ran the car up to 180*F in the garage with the ball valve "Open". Yes, you guessed it the heater core was bad. With heat controls on, mist was flowing through vents and fogging up the windshield and the passenger side carpets got a green bath. That is all cleaned up now and I face that nasty job ahead. I will just use the waterpump to intake bypass method to keep driving this season.
But I must say that I am pretty disappointed with the AC Delco product. Perhaps Chinese or Canadian (Spectra Premium) might be better. I really do not know what to order at this point. It's a pig-in-a-poke when it comes to quality. I may just go NAPA and hope for the best. I am frustrated.
Le Mans Master
Joined: Oct 2006
Posts: 6,842
Likes: 285
From: Palmdale CA
What a drag! And knowing you, you probably had the best coolant you could run, regular changes, etc and now, you're faced with a sucky project. I had the same thing happen in a Ford Escort ten years ago, full on windshield fog, water on floor, mist etc.
My brother at the Ford dealership told me to use the Barr Stop Leak and I did. Stopped the leak quickly and I drove it for another three years, in the very hot, High Desert of Southern California without a peep or problem from the heater core and it all worked well. I'd be tempted to do it to my 74', that's for sure, especially since you just did it (and I just did mine a few months ago, so I know what it's like to pull the heater core, I think it's closer to the vehicle giving birth to it, than actually pulling it out...)
My brother at the Ford dealership told me to use the Barr Stop Leak and I did. Stopped the leak quickly and I drove it for another three years, in the very hot, High Desert of Southern California without a peep or problem from the heater core and it all worked well. I'd be tempted to do it to my 74', that's for sure, especially since you just did it (and I just did mine a few months ago, so I know what it's like to pull the heater core, I think it's closer to the vehicle giving birth to it, than actually pulling it out...)
Thread Starter
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
What a drag! And knowing you, you probably had the best coolant you could run, regular changes, etc and now, you're faced with a sucky project. I had the same thing happen in a Ford Escort ten years ago, full on windshield fog, water on floor, mist etc.
My brother at the Ford dealership told me to use the Barr Stop Leak and I did. Stopped the leak quickly and I drove it for another three years, in the very hot, High Desert of Southern California without a peep or problem from the heater core and it all worked well. I'd be tempted to do it to my 74', that's for sure, especially since you just did it (and I just did mine a few months ago, so I know what it's like to pull the heater core, I think it's closer to the vehicle giving birth to it, than actually pulling it out...)
My brother at the Ford dealership told me to use the Barr Stop Leak and I did. Stopped the leak quickly and I drove it for another three years, in the very hot, High Desert of Southern California without a peep or problem from the heater core and it all worked well. I'd be tempted to do it to my 74', that's for sure, especially since you just did it (and I just did mine a few months ago, so I know what it's like to pull the heater core, I think it's closer to the vehicle giving birth to it, than actually pulling it out...)
The job is a real treat!
Last edited by Paul L; Aug 26, 2013 at 07:46 PM.
Thread Starter
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
Just a theory but here goes. The hoses come up from the bottom of the car into the core spouts coming down. The GM/OEM heater hoses have a molded 90* curve on the end. I should have used those originally but instead just used ordinary heater hose in 2008. I think the lack of the molded end and with engine vibration it caused stress on the heater core spouts and led to failure of the soldered ends. So perhaps my own fault. Live and learn!
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
Or a better choice would be to remove the entire heater core. With the heat the car generates already, and the fact I have no plans to drive in the winter, I have no need for the heater core, the leaks, the weight or the plumbing. I know, its not original, but my car will only have what I need to drive it and have fun.....all fancy accessories will be removed.
Drifting
Joined: May 2005
Posts: 1,968
Likes: 44
From: East TN
...and sometimes you lose. Five years ago my heater core (with A/C) went bad. So I bought the super-duper, AC Delco, Made in USA version so I would not have to repeat that difficult job.
When I was coming home from a show yesterday-Sunday (I posted pics here) I noticed a "sweet" smell at red lights and I lost some coolant from the overflow tank. This was with my shut-off ball valve in the 5/8" hose on "Off".
When I was coming home from a show yesterday-Sunday (I posted pics here) I noticed a "sweet" smell at red lights and I lost some coolant from the overflow tank. This was with my shut-off ball valve in the 5/8" hose on "Off".
Melting Slicks
Joined: Aug 2005
Posts: 2,683
Likes: 34
From: Working on the car NY
Don't go to NAPA. Before you buy that Specta core, check the dimentions in thickness - when I tried it, it was 2" vs. my required 2 1/2". It said 2 1/2" on the ad sheet for thickness but when it came in, it was 2". This was at NAPA. I ended up buying a "Vista" unit from either Summit or Jegs.
http://forums.corvetteforum.com/c3-g...e-69-w-ac.html
http://forums.corvetteforum.com/c3-g...e-69-w-ac.html
Last edited by TWINRAY; Aug 27, 2013 at 10:21 AM.
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Melting Slicks
Joined: Dec 2000
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From: Lansdale 19446 PA
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Just a theory but here goes. The hoses come up from the bottom of the car into the core spouts coming down. The GM/OEM heater hoses have a molded 90* curve on the end. I should have used those originally but instead just used ordinary heater hose in 2008. I think the lack of the molded end and with engine vibration it caused stress on the heater core spouts and led to failure of the soldered ends. So perhaps my own fault. Live and learn!
I agree the vibration is part of the problem and the weak soldering doesn't help.
It was in the winter of 97/98 that I installed the new core and the summer of 98 that I had to do it again - been fine since.
Burning Brakes
Joined: May 2007
Posts: 1,022
Likes: 33
From: Lokeren, Belgium
Bought the AC heater core myself, went to a radiator repair shop (starting to get scarse), they took it apart, soldered and reinforced everything. This was my 3rd heater core change and I sure hope it was the last.
Nick
Thread Starter
Team Owner
Joined: Aug 1999
Posts: 30,995
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From: Ontario
Family matters took up my day but I ordered the core and molded hoses. I'll get at that job probably late next week. Tomorrow I will do the bypass. There is no need for a heater as yet. It is 82*F as I type.
The suggestions to get a local rad shop to re-solder and re-inforce the new core (or even the old if the new one does not fit) is good advice. I believe there are 2-3 shops left in town but we shall see. This is a job that I had not expected this year but we do have fun with these cars, don't we....
The suggestions to get a local rad shop to re-solder and re-inforce the new core (or even the old if the new one does not fit) is good advice. I believe there are 2-3 shops left in town but we shall see. This is a job that I had not expected this year but we do have fun with these cars, don't we....
Les
Thread Starter
Team Owner
Joined: Aug 1999
Posts: 30,995
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From: Ontario
Getting ready for the leaves now! And more pics (with the top down and heater on
). Geez, I might even put the vinyl hardtop on!
Thread Starter
Team Owner
Joined: Aug 1999
Posts: 30,995
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From: Ontario
I suppose so. It's cute when you turn on the heater and defroster and the car becomes a misty sauna. Well, perhaps not cute but just verification that it's not just the worm clamps that need to be tightened. Mais, c'est la vie (that's life).
Race Director
Joined: Jan 2000
Posts: 12,399
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From: San Jose CA
Certainement, c'est la vie, et par ce voiture, seulement le commencement. Je ne pense pas c'est la case pour ta Corvette.
Thread Starter
Team Owner
Joined: Aug 1999
Posts: 30,995
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From: Ontario
Overall this has been a fun car.
Team Owner
Joined: Jul 2004
Posts: 40,412
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From: Redondo Beach, California
My 68 has the original heater core. When i pulled the original engine in 2005?, I could see absolutely no rust in the engine/cylinder head water coolant cavities. All of the water cavities were white...covered with a white cover of coolant silicates. From 1972 to 2005, there had been no water in the coolant of this engine. From 1972 until now, with a new ZZ4 engine, the coolant has never been anything other than 100% ethylene glycol. No water. My Daily Drivers, a 1995 Cadillac Seville and a 1997 Ford Thunderbird also have 100% ethylene glycol coolant...no water. No water equates to no corrosion.
Also, with no water, your coolant system will never pressurize. When I took my ZZ4 for a first drive, I just pushed the coolant hoses on fittings with no clamps for a first drive!! Well, OK here I outsmarted myself. Sure coolant heating would not create coolant system pressure, but the "water" pump creates a lot of flow pressure. In the course of driving my new car around the block, I revved up the engine and blew off the hose going to the heater radiator. What a mess, it ruined my 68 fiberglass tunnel insulation which I had to replace. .....if you have a 70 and up C3, you don't have this insulation..you should have.. It's not expensive to add.
Also, with no water, your coolant system will never pressurize. When I took my ZZ4 for a first drive, I just pushed the coolant hoses on fittings with no clamps for a first drive!! Well, OK here I outsmarted myself. Sure coolant heating would not create coolant system pressure, but the "water" pump creates a lot of flow pressure. In the course of driving my new car around the block, I revved up the engine and blew off the hose going to the heater radiator. What a mess, it ruined my 68 fiberglass tunnel insulation which I had to replace. .....if you have a 70 and up C3, you don't have this insulation..you should have.. It's not expensive to add.
Last edited by 68/70Vette; Aug 28, 2013 at 12:24 AM.