I am in the middle of a heater core replacement job. I have decided to go with aluminum, can anybody please advise as to which manufacturer is best. I appreciate any and all input.

 

The one that does not leak. Ha ha.
Simply put. It' not a job. You would like to re-do.

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Price is a razors edge.
highest price does not make it best.
Lowest price typically has a reason.
Unfortunately to many variables. Between

 

Good deal. Thank you for the info.

 

I recently did this job and went with original copper heater core, found NOS at a radiator shop. I will NEVER do this job again, it sucked that bad. I asked the radiator shop if they would do it and they said they would give me a deal on the core so that they wouldn't have to do it. Watch out for aluminum ones if you nick it putting it in you'll only find out when your done. If you do go aluminum pressure test it before putting it in and be very careful. I only paid $125 for my original chevy core. Call around to radiator rebuilders and you might get lucky.

 

You'll learn that they basically built the entire car around the damn thing, and from now on you'll change out your coolant on a 2-3 year schedule to help keep it from happening again.

 

FWIW, got a heater core from NAPA - about 10 years now w/ no issues.

 

Make sure to go ahead and replace the plastic clip inside the heater box. And they sell radiator hose grease in little packets, though they seem to not carry that much anymore. Though I think it's basically the same as silicone high temp brake grease. As you'd want to put that on the heater core nipples to help the hoses slide on without putting a lot of pressure on the core.

I also got some strip caulk to pack around the heater core nipples on the outside to help seal that area off from the engine bay. I'd drive it around for a while before putting the plastic heater box back together to make sure it isn't leaking.

When I did mine, I believe I got a rubber cap and clamped it onto one nipple. And then got a pressure gauge from Lowes. And clamped that to the other nipple and then used a foot pump to put pressure into the heater core and then stuck it in a bathtub full of water for a few days to check for any bubbles and also check the gauge for pressure drop. And the gauge was also used so you didn't pump too much pressure into the core. I forget what the max pressure is when doing this method as it was years ago I did it as I went based on info I read either on the forum or the internet somewhere.

 

I believe I read in one of those Corvette Magazine articles, that's up online, on replacing the heater core in a C4 is that I believe they recommended using an aluminum core over a copper core as I believe they said the copper core is more prone to corrosion that would then lead to leakage. I used an aluminum core many years ago, though that company had stopped making them. And it was one of the last ones available at the time as it was recommended as a good brand. There was a period of time when you couldn't really find a C4 heater core. My factory copper heater core that I removed had corrosion where it was leaking at.

I do remember when I did mine, there was a big deal of people having to be tubes on some brands in order to get them to go through into the engine bay as apparently some brands didn't have them bent correctly. So you'd want to make sure the core you get that you don't really have to bend the tubes in order to mount it. I seem to recall having to slightly bend on of my tubes in order to keep it from touching the firewall, as that could wear a hole in it from vibration.

One other tip is to slide something thin over the ends of each tube, like painters tape, to keep from getting crud in the tubes during installation. As I believe my C4 had a gooey substance from the factory at the inside firewall where the tubes go through.

Also, this is a good time to go ahead and replace your thermostat and change your coolant. I use Zerex G-05 and distilled water. Which is a 5 year coolant.

 

Awesome info…thanks!