Belgian1979vette

Hi,

My heater core started leaking just now after a pressure test on the cooling system. Are there good replacements ? Would it be a good idea to have it repaired. Some greenish color on some of the copper here and there.

Thanks

Jud Chapin

It's a huge amount of work to replace one so you might want to try some radiator sealer first to see if that stops the leak. If you do end up replacing the core, stay away from Autozone, etc. I think I replaced mine with one from Zip which fit the box correctly.

Belgian1979vette

Some work, but as the interior is not complete yet, doable. Core is already out, tested and leaked around one of the tubes. Probably a break when I had to remove the hose to put on a new strap after the bolt on the last one broke.

I would like to avoid a future leak. There is some greenish color on some of it indication some corrosion.

dembo

Took it to a radiator shop (yes there are still a few around in Belgium). They took it apart, resoldered the tubes and soldered a new core in between the two halfs. To be on the safe side I addes cold solder around the tubes from the outside. Why not a replacement? Because most of them are crap, with the original sides and tubes, no issues with fitment.
Nick

74 LS4-454

get it repaired if possible, as Jud mentioned stay away from the local auto stores as they do not fit properly. bought one from Pep Boys and it was smaller than the original. called Zip and they measured what they had, and it fit perfect in the 82. I still intend to get the original repaired sometime in the future.

pokey1

Corvette Central has the correct replacement core. Just put one in my 81 and it was identical to the original.

redvetteman81

I need to replace mine in my 81. est time to do the job?

Belgian1979vette

Cannot really say, because mine was in a body off resto. Interior was not yet complete (dash was in) which greatly simplified things.

what you have to do is :
- drain cooling fluid
- disconnect the tubes at the engine side
- Take the tach/speedo out
- take the gauge cluster out
- disconnect the wires going to the light and wiper switch
- take the glove compartement out
- loosen the flange on your steering column, pull it slight towards you to disengage it, and lower it (might need to take out the chair for this as well)
- take the dash out
- loosen the nuts on the engine side holding the ventilator housing
- disconnect the cable going from the heater to the housing
- disconnect the vacuum lines to the housing.
- pull the housing out
- you can see the heater core : screw the holding bracket out and pull it out. When you're in there it might be a good idea to clean the housing and replace all gaskets.

drwet

You don't have to do all this. You do need to remove the seats, the centre console side covers and loosen the console top panel so you can remove the center gauge cluster. Take out the glove box. Now you can remove the heater box in its three pieces. The dash will flex enough that you can get them out. There is no need to remove the tach, speedo, steering column, or dash pad.

Easy Mike

Copper oxidizes to a green.

Belgian1979vette

Are you willing to risk a dash ripping ?

I had my unit repaired. Apparently there was also some crud in there preventing the core from working properly. Tried to get it in, but one of the ears on the inner box broke off Damn.

Jud Chapin

Don't feel bad, I broke my console plate doing this job.

drwet

Yes you certainly have to be careful when you're working on these things. I don't think they were designed to come apart and when they're thirty years old it only gets worse. Regardless, I don't think there's any greater chance of damaging the dash pad by flexing it a little to get the heater box out than there is by removing it. I've done it several times with no damage. The greatest risk of damage to the dash pad is probably when removing the gauge cluster. It tends to get caught on the vinyl and you risk tearing it. Just be very careful!

TWINRAY

Well, I never clock on how long it takes me to do stuff but I will say that doing the heater core on my AC'ed '69 ranks right up with "worst stuff I'd like to do again on my car." It's all the ductwork that is the problem and the problem lining them up again right when you put it back. I also did the heater core on my non-AC'ed '67 and it was substancially easier. Since I was "at it" in the '69 swap, I did all new interior vacumn (heating/AC) hoses which was also a lot of fun.

Belgian1979vette

Although bad, the bumper and all other hardware up front was the worst for me.

Second was debugging everything after the body off resto.

This is probably a good third, but nothing on this car is ever easy. A big car but virtually no room to decently wrench on it...