Inpheksion

Hello everyone. Recently the cabin of my daily driver started faintly smelling of coolant, and the windows get a little foggy now. I am assuming that it is the heater core, none has dripped onto the floor yet, so I am still driving the car, as I do not notice a large amount of coolant lost day to day (checking both radiator and overflow tank daily).
I plan on replacing the heater core in a few weeks, once my school semester comes to a close. I have read some threads and watched some videos on how to do this job, and it doesn't seem that terrible on an 88 (I'm just thankful I don't have the refreshed interior)
I noticed that there are quite a few brands on RockAuto, etc. I was just wondering if anyone had any recommendations on what brand to go with, and if there are any brands to stay away from.

Thank you very much! I appreciate any help and info you guys share.

Car is a 1988 Z52 w/ 170k, I have recently replaced the radiator (leak on the bottom) and the intake gaskets, so I am guessing that the coolant system is just working all the weak points out of itself now.

Red86Z51

I installed a Spectra Premium 94494 from Rock in my '87. I have been completely happy with it...and so far I've gotten to use it in temps as low as 8º and it kept me nice and warm.

You could spend a lot more buying one from any of these specialty Corvette vendors (and pay their "Corvette Tax" )...but why???

Joe C

for my 85, I bought a replacement heater core from NAPA. I've got to admit, I did not install it, but the shop that did, didn't seem to have issues. it's been in the car about five years now.

GREGGPENN

I posted a thread a few years ago (4?). I had problems with at least one brand from Rock auto. It wasn't Spectra but I wanted the original copper (higher-priced) replacement. I don't remember why...but it had to do with the advantage of copper versus aluminum. More reliable welds, maybe? Better entropy? I don't remember.

I ended up finding a good unit from Advanced Auto. The main issue was whether the necks were bent/fit correctly. Theirs did. As usual, I looked for price within the copper units.

I'm a bit leary of Rock these days. I think they carry a lot of 2nd-tier/quality stuff. I've had to return over 50% of the products I've bought from them.

Hot Rod Roy

I like to see the quality of the products I'm buying, so I patronize my local sources. I purchased a Murray heater core from O'Reilly Auto Parts for under $35. It was made in the USA, and is an all brass construction, and it fit fine. It's a challenging job to replace to core, and there are good suggestions in the Sticky section of this forum.

If you're having problems with your cooling system, are you changing your coolant as recommended?

GREGGPENN

To be clear, it won't drip ON the floor where you'll see it. Coolant rolls down the firewall, under the carpet and soaks into the padding underneath. If you wait until you SEE it, there will be a lake in your passenger floor pan!

Tom454

I have also had a lot of issues/returns with Rock Auto- as mentioned, about half the parts I purchased from them were returns from other customers... greasy open boxes, supporting parts missing, previously installed parts. I still buy from them, but I am leery as well.

WW7

I agree with Gregg, if your not going to replace the core real soon, you may want to go to Advance Auto and get a bypass tube..This is a brass or copper tube with 5/8" on one end and 3/4" on the other , you pull both hoses off the core in the engine bay and slip them on the tube and tighten down the 2 clamps..This will stop any coolant from leaking on the floor....You will be cold , but dry.......WW

mtwoolford

chemically, brass is less reactive than aluminum; that's just another way of saying that brass is much more resistant to corrosion.

Inpheksion

Thanks for all the input guys. I am probably going to do it in about a weeks time. I did not know these cars dont drip on the floor. If I was going to wait any longer than I was, i would get the bypass hose, but I haven't noticed any appreciable loss in coolant over the past 3 weeks, so I am just going to hold off for the last week.

Right now I am deciding between a Spectra or an APDI. Both are about the same price on Amazon, but the APDI is copper (normally $70, says it is marked down to $35)
Someone mentioned that they had a good experience with spectra, has anyone dealt with an APDI product before?

Also, I changed the coolant at around 162k when I did the water pump, how often are you supposed to change it? And I am just using green, is that okay?

Thank again everyone!

WW7

If your car has green coolant now, then replace with green...I believe green is what it came from the factory with.. I change my coolant about every 3 years, I drain the whole block, not just the radiator...
Which ever core you decide to go with , check it out in a tub of water before putting it in the car. Put a plug with clamp on one of the tubes, then put a heater hose with a clamp on the other tube with a valve stem in the end of it so you can add pressure. Then put around 18 to 20 pounds of pressure into the hose with the core under water, you will see bubbles if it's leaking....It's better to have it leak before it's installed in the car then to have to go through the installation again.......WW

colter

What are the good C4 heater core brands?

Was looking at the heater cores from Advance Auto. Though the pictures on the Advance website "Carquest ToughOne" are the same pictures on other sites under the APDI/PRO brand.

THE 383 admiral

Make sure you purchase the highest quality Heater Core!! It is a very tedious job. You will not want to go back in there again any time Soon!

colter

What's the "highest quality"?

I don't think you can get the GM heater core anymore. As that is what people used to recommend.

I've not seen any consensus on which aftermarket heater cores are the "highest quality".

FOURSPEEDVETTE

Get a "Spectra" brand heater core. Installed mine (myself) a few years ago. It's an exact match for the old one and it has performed flawlessly.

colter

I'll keep an eye open on the different brands. Read someone post a couple of years ago that the "Spectra" heater core didn't fit. Also the poster said he called Spectra who stated they were aware their core doesn't fit the Corvette.

Don't know if "Spectra" actually makes theirs or uses someone else. Possible maybe they change makers or suppliers or something with a different design.

FOURSPEEDVETTE

It's been about two years ago that I got mine. As I said, it was a perfect match in size and quality.

colter

Spectra is a NO GO.

Bent the tubes around to try and get them looking close to the OEM. Problem is still couldn't get the Spectra mounted without force.

The problem is the upper tube is too long before they bent it. And so when mounting the heater core. The upper tube is hitting up against the firewall hole edge before the heater core body is sitting flush with the heater box. So that keeps you from setting the core flush to the heater box without forcing it.

I could have maybe bolted the core down to try and get it to sit flush. But that would have put unnecessary pressure on the upper tube not including vibration on that upper tube from the firewall which would probably lead it to fail early.

Seems like to me the heater core should be able to sit flush inside the heater box without the tubes touching anything.

JrRifleCoach

Which ever brand you settle on be sure to follow this suggestion.

Take the core to a radiator shop and have it inspected and pressure tested.
No need to learn its weaknesses after installation.

Remember some of this inventory has been sitting on shelves for years.

colter

I couldn't find anyone who could pressure test the core off of the car. There are adapters you can buy to use with a Mityvac to pressure test the heater core. But instead of buying that for a one time use. I'd probably just connect the heater core up, run the car for a bit to get rid of the air, then connect a coolant pressure tester up to the radiator and pressurize it to 16psi and pump it up to keep it at 16psi every so often for a few days to see if the core would leak before putting the rest of it back together.