81 Heater Core advice
Thread Starter
Racer
Joined: Nov 2001
Posts: 478
Likes: 3
From: Huntsville AL
81 Heater Core advice
Ok, so I replaced my heater core in my 81 vette in 2003 (Advance Auto heater core Lifetime warranty and always have it pressure tested). Again in 2008 under warranty no charge for the new one. And again replacing it now at no charge for the new one but as you know this is a lot of work.
Anyone getting more than 5 years from theirs before they start leaking? If so what brand are you using? My car is driven less than 500 miles a summer and always garage kept, so there is not that many pressure cycles on them, and it never overheats. Or maybe it is the type of antifreeze I'm using (prestone 50/50).
Any recommendations would be greatly appreciated as I really hate to keep doing this PITA job.
Thanks,
YBnormal...drive a vette
Anyone getting more than 5 years from theirs before they start leaking? If so what brand are you using? My car is driven less than 500 miles a summer and always garage kept, so there is not that many pressure cycles on them, and it never overheats. Or maybe it is the type of antifreeze I'm using (prestone 50/50).
Any recommendations would be greatly appreciated as I really hate to keep doing this PITA job.
Thanks,
YBnormal...drive a vette
Thread Starter
Racer
Joined: Nov 2001
Posts: 478
Likes: 3
From: Huntsville AL
Only change the coolant when I have to do some work like this, would think it would last 5 years. As far as the cap it was replace but can't see that making a difference. Maybe these heater cores I buy at advance auto are only designed to last 5 years...LOL
Anyone have any heater core experience as far as design and workmanship?
Thanks,
YBnormal....drive a vette
Anyone have any heater core experience as far as design and workmanship?
Thanks,
YBnormal....drive a vette
Burning Brakes
Joined: Mar 2006
Posts: 829
Likes: 131
From: Spartanburg SC
I replaced mine 6 years ago, from NAPA. No problems. I will say this about Preston all makes all models antifreeze. I used it for several years in all my cars. I had to replace the water pump on every one of them within 18 months and the heater core in two of the three. May be coincidence, but I don't think so. I now run the original green Zerex in the vette, and always will. Everyone of the automakers specify a specific coolant in their cars. I'm using what they say.
Race Director
Joined: Jan 2007
Posts: 10,682
Likes: 696
From: Danville Illinois
2025 Corvette of the Year Finalist - Modified
2024 C3 of the Year Winner - Modified
2021 C3 of the Year Finalist - Modified
2019 C3 of Year Finalist (appearance mods)
The green stuff, yes that's what i use, in 40 years, two radiator repairs and two water pumps, too late to change now.
Just replaced the heater core, from Napa this summer, will let you know in 10/15 years.
Later
Just replaced the heater core, from Napa this summer, will let you know in 10/15 years.
Later
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
Do you have the small clamp holding down the spouts installed? If not the heater hoses can put pressure on the spouts and a fracture in the soldering can occur. (I'm assuming the clamp set-up is similar to my 1974.) Some cores are not configured properly and the clamp cannot be used.
Race Director
Joined: Jan 2007
Posts: 10,682
Likes: 696
From: Danville Illinois
2025 Corvette of the Year Finalist - Modified
2024 C3 of the Year Winner - Modified
2021 C3 of the Year Finalist - Modified
2019 C3 of Year Finalist (appearance mods)
Yes, i had the small clamp and put it back on the new one also, had to tweak the tubes somewhat tho.
Last thing i did was take the unit to the local radiator repair place and have them test it before putting it in.
Last thing i did was take the unit to the local radiator repair place and have them test it before putting it in.
Thread Starter
Racer
Joined: Nov 2001
Posts: 478
Likes: 3
From: Huntsville AL
Yes I'm using the clamp and never try to tweek the tubes, solder joints don't look that strong (All have fit very well with the clamp installed). I think this time I will try to use Zerex and see if I can get more than 5 years out of this one. One thing is they never start leaking at the solder joints but just inside the lower tube.
Thanks for the replies
YBnormal...drive a vette
Thanks for the replies
YBnormal...drive a vette
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Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
Yes I'm using the clamp and never try to tweek the tubes, solder joints don't look that strong (All have fit very well with the clamp installed). I think this time I will try to use Zerex and see if I can get more than 5 years out of this one. One thing is they never start leaking at the solder joints but just inside the lower tube.
Thanks for the replies
YBnormal...drive a vette
Thanks for the replies
YBnormal...drive a vette
Instructor
Joined: May 2013
Posts: 186
Likes: 18
From: Lower Mainland British Columbia
I will be replacing my 81 heater core this winter also. Don't recall where, by I have seen advice to take the new heater core to a rad shop and have them re-solder the joints for the inlet and outlet just to be sure. This is what I plan on doing as it does not look like a job I want to do again.
Kevin
Kevin