Replacing the Radiator and Radiator Core Support

Since I had purchased a bunch of parts for the '75 Corvette I was planning to restore (which I decided to sell), I ended up with a good selection of stuff that would fit my 1976 model.

As a side note, you need to be very careful when you purchase parts from private sellers, since parts that fit one year may not fit newer or older C3 models.

A reputable Corvette parts reseller will know this and help you get the right parts.

In this case, the 1975 Corvette radiator and core support would fit my early production '76 and that helped me save a bunch of money from having to purchase yet more parts.

Here is what the old radiator and support looked like. And even though the original core support was not that bad, repairing it would've probably cost more than buying a new one.

The previous owner had spray painted the core support and shroud using whatever paint he had handy. Not sure if he did this to help protect and/or beautify the area, or with hopes that a potential buyer (me, in this case) would think that the car was in great shape.

Actually, when I notice that someone has spray-painted under the hood, I suspect some damage. In this case, I crawled under the car and inspected the radiator core support as best I could, and I could only see a small amount of rust. Core supports of C3 Corvettes are notorious for being susceptible to rust.

This is the new radiator core support after it was installed along with the air conditioner condenser, which is mounted to the core in front of the radiator. I debated about having the new support powder coated, but timing these things can be tricky and take forever.

In the end, I just decided to leave it as it came from Coffman since the car will always be garaged and driven only in fair weather.

The pictures below show the original radiator core support. Not horrible, but definitely in need of repairs if it was to be used again.

As the close-up photos show, the bottom edge had rusted through. These parts can be repaired by welding new metal to them, but when rust is extensive, there's little good original metal to weld new pieces to. 

At the end of the day, these projects are time-consuming and can end up costing more than new replacement parts.

For illustration purposes, this is what a new radiator core support looks like.

I also had new rubber seals for the support, as well as new upper and lower radiator hoses.

The brand new radiator was not cheap, but sometimes getting new parts is the only option. Radiator repair shops are a rarity nowadays, and Corvette parts are expensive.

Again, just make sure you buy the right parts for your car. If you have a car with automatic transmission and air conditioning, for example, the radiator has to be equipped accordingly, so the tranny cooling lines can be connected to it.

If you have a manual transmission, like my '76 does, you can plug the inlet/outlet holes. Alternatively, you can also use an aftermarket aluminum radiator, but make sure it will fit your application without the need for modifications.

full aluminum radiator offers many advantages over its copper counterpart. It will be 30 to 40% lighter; it will be 100% aluminum and aluminum brazed (this eliminates dissimilar metal issues); aluminum dissipates heat better; you can polish aluminum to a mirror shine for car shows; and more.

Having said that, if you're after a factory look, an aluminum radiator is not the way to go.

As I mentioned earlier, the radiator shroud had been spray-painted black, and it looked ratty. So the first order of business was to wash it thoroughly, remove all the old paint, prep it properly, and give it a fresh coat of paint.

However, once the old paint was removed, it revealed a very cool "marbleized" plastic finish, which I decided to keep.

To that end, I sprayed several coats of gloss clear engine enamel paint after the part had been completely degreased. After the paint had cured, I applied the foam seals where it comes in contact with the support core.

I also took the time to detail a lot of the brackets and hardware. The time to do this is when the parts are off the car. I sprayed all brackets with Eastwood's Underhood Black paint since it has the correct sheen. The results speak for themselves.

And here's the radiator, core support, shroud, and brackets installed. And while all this work was being done, my mechanic discovered that the fan clutch was leaking, so we ordered a new replacement radiator cooling fan from a local auto parts store.

Thank you for following my '76 Corvette Blog!

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Eastwood Acrylic Underhood Black Semi-Gloss Paint | 11 oz.
VHT Engine Enamel Gloss Clear Spray Paint | 11 oz.
Rhino Ramps (12,000 pounds)
Hopkins Heavy-Duty Wheel Chocks
1973-1976 Corvette Full Aluminum 3-Row Tri-Core Radiator
1976 Corvette Upper Radiator Hose | Gates 20809
1976 Corvette ACDelco Lower Molded Radiator Hose

1973-1976 Corvette Radiator Core Support