Copper or Aluminum Core ?

[Kevin Bielinski #13320]

That's my choice for a new radiator. What's the advantages of each. The car is a 1970 Coupe DeVille. I know the aluminum is lighter in weight.
 

[Gene Beaird]

I recently ran into this when the radiator on our recently-purchased 79 Seville radiator sprung a leak.   

I was put in touch with a local guy who's been doing radiators for decades (he inherited his radiator shop business from his father).  He's done several of the radiators for our LeMons race cars.  But I digress. 

I had checked with the local parts house, and they listed a copper radiator for like $250, and a 'replacement' aluminum with plastic tanks radiator for $120.  I ordered the copper radiator thinking I had scored.  Unfortunately, the opened box that arrived contained an aluminum/plastic radiator.  I ordered the other one they had in stock at the warehouse, and opened the box to find yet, another aluminum/plastic radiator.  That's when I started looking elsewhere.  I called the guy at the fore-mentioned radiator shop, Echols Brothers Radiator Works in Houston, by the way to discuss my options.  He indicated that he could replace the copper core in the existing radiator but the price would start at around $500.  He also said he could get a replacement all-aluminum radiator for almost half that price.  He indicated that the aluminum radiator is more efficient than copper, and that the aluminum/plastic replacement type radiator, even with a thinner core, would probably provide just as much cooling, or more, than the factory copper one.  He said the all-aluminum one would have similar dimensions in the core, so should offer even better cooling capability than the copper one. 

So, I got the all-aluminum radiator, installed it, and never looked back.  That was last month.  The car doesn't get much road use, so I don't know how well, or poorly it cools yet.  Summer has yet to set in.  It ran well for the little time I've been in the car, though. 

I did put a quick buff on the tanks and top, though, so it does brighten things up under the hood a bit.  Definitely not stock, but this is going to be a fun car, not a 100-point concours show car.  It looks soo pretty. 

I did notice that the other day, after I moved the car, there was a puddle of water under the front.  I figured one of the hose clamps just wasn't quite tight enough.  It happens often when reinstalling cooling hoses.  I checked everything and it was dry.  I then noticed that the radiator cap was cockeyed on the filler.  I checked and it appeared that the neck was malformed.  It was perhaps dropped before I got it, ever-so-slightly bending one corner of the neck.  I went at it with an assortment of small prybars and flat screwdrivers and got it fixed so a cap tightens correctly against it now. 

So in my rambling, I'd conclude that a copper core radiator, while not as efficient, and way more expensive, would be the way to go if you plan to show the car.  If not, you should be able to go aluminum, as it's more efficient than copper but a little cheaper.  You can paint everything to make it _look_ like a factory radiator, but the tanks won't be shaped the same. 

[mgbeda]

I thought that there was a chemical problem with the iron in the block somehow interacting with the aluminum in the radiator and causing corrosion.  I know all newer cars have this set up but I think they use different coolant and they get driven a lot more (so the coolant doesn't sit still) and I think they just accept that they won't last as long.

If you can find a local radiator shop and your old radiator isn't too bad you can get the original radiator "rodded out" (basically a little tiny roto-rooter job) and small leaks soldered.  This was the standard practice back in the day and it was cheap and durable.  I had this done on Bessie in 1988 and drove her everyday for the next seven years and occasionally for the next nine, about 100,000 miles, without any more radiator problems.

-mB

[Kevin Bielinski #13320]

I'm wondering as well about the iron in the block somehow interacting with the aluminum in the radiator and causing corrosion as well. I've gone through 3 radiators since 2000. All of them have startes to leak from the core. The car sees about 500 miles a year.

[76eldo]

Iron block with aluminum radiator should be create any problems at all.  Electrolysis occurs when two dissimilar metals are touching each other like a common steel bolt in the aluminium trunk lid of an Allante.

It's really a matter of appearance and having the proper look.  The original style rads are no longer being made and a plastic tank aluminium unit won't do the job.

Re-coring is the best option.

Brian

[Art Gardner CLC 23021]

Supposedly, copper cools better than aluminum.  It certainly is more durable.   I think manufacturers went to aluminum to save weight (which for the mfgr, equals cost).  Walker Radiator in TN still makes copper radiators, for nearly anything.  I had them make one for a 49 Cad a few years ago and was very satisfied.

[Gene Beaird]

I'm wondering as well about the iron in the block somehow interacting with the aluminum in the radiator and causing corrosion as well. I've gone through 3 radiators since 2000. All of them have startes to leak from the core. The car sees about 500 miles a year.

The shop owner I talked with did recommend I ground the radiator by adding a ground wire from the top of the radiator (there was a flat spot at the top that was easy to tap for a machine screw) and connecting it to the body of the car.  I used the brace for the Automatic Ride Leveler pump. 

[Kevin Bielinski #13320]

I received the new copper radiator. It's a 4 core and will not fit an air conditioned car.

[bcroe]

With the old standard copper radiator industry gone, I had my last one
custom made.  I received an excellent radiator, which was available also
in a premium cooling version (extra cost).  This 4 row was mated to 3 row
tanks, so it fit my mountings.  But the actual core was thicker than my
old 3 row.  Since the shroud touched the core, I had to trim the shroud
there to fit.  Not cheap, but my temp gauge no longer drifts, it is anchored
to the thermostat rating. 

I believe usradiator.com was where I went; before I was done, the paperwork
said COOL CRAFT COMPONENTS.  Bruce Roe

[dadscad]

I purchased a new HD 4 row copper radiator for my 63. Fit and looks like the original. They have a listing for your 70, try here,     http://www.usradiator.com/radiators/cadillac.html?p=2  or here,  http://www.usradiator.com/

HTH,
David