One solution to overheating

[Lucas Feininger #15674]

I am posting this for anyone who is having persistent overheating problems with their vehicle.

When I bought my 1963 Series 62 convertible 13 years ago, the car would regularly run hot (temp gauge needle between 3/4 and H). Any kind of slow traffic, especially after driving at expressway speeds, would cause the engine to get very hot.

I went from a 2-row to a 3-row to a 4-row radiator without much success. The larger radiators helped a little but the engine still ran very hot.

After my "new" 4-row radiator started leaking for the second time I decided to try a different approach. I contacted a company called Alumitech Reproductions in Pinckney, Michigan. Alumitech Reproductions specialize in custom-made aluminum radiators for big-blcok performance cars. I called them and they said they would be willing to make up a brand-new aluminum radiator for my vehicle. I sent them the old radiator to use as a pattern and a month later I had a very close reproduction in aluminum. I made some modifications to the design, including switching the inlet to the opposite side of the radiator for cross-flow (the original radiator has the inlet and outlet on the same side --  a very poor design). The new radiator features twin SPAL electric fans so I got rid of the engine fan and fan shroud. The new radiator dropped right in and was easy to hook up. Even wiring the fans was a piece of cake. The one thing I had to modify later was to add a threaded socket (under the inlet) for the fan switch, which normally goes into the temp gauge socket in the head. I wanted to keep my temp gauge so I had the threaded socket welded in.

Now the car always runs nice and cool. The temp gauge never goes over 1/4. Yes, I have lost some originality but I always wanted to enjoy my car as a "driver", and having eliminated my overheating problems has greatly enhanced my enjoyment of my car.

Lucas Feininger
CLC #15674
1963 Series 62 convertible

[TJ Hopland]

Just curious what did the radiator itself cost?  And then the fans and related controls?

I have heard that the typical aluminum radiators like you see all over ebay are terrible as far as cooling capacity and not so good as far as strength.  Apparently they are made as thin as possible and are not at all engineered so their cooling capacity stinks.   Apparently their engineering is so that it looks about right. 

The other thing I thing that can have a large effect on cooling especially on the highway is all those seemingly useless baffles and deflectors that often get damaged or lost over the years when other work gets done.   I dont know much about aerodynamics but the little I have observed seems to defy typical logic. 

[Dave Shepherd]

My thoughts here are these cars when new did not have overheating issues, what is the root cause of your problem that you had to go to such extensive modifications to correct the overheating, interesting problem.  Both the 59 and 57 Sevilles I worked on my shop have had no problems with overheating with the original design systems.  Did your 63 have a fan clutch?

[Walter Youshock]

I'll agree with Dave on this one.  My '57 always seemed to run hot but rarely overheated.  After a thorough radiator and block flush (the block was so corroded I had to poke an awl in the block drains just to get a drip.), I've had no problems. 

Non-air '57's have a 4-blade, non-clutch fan and, although you might be able to fry an egg on the air cleaner after a good run, the car does not register "HOT" and doesn't overheat.  My car also has the original radiator and cap and the engine has not been rebuilt.  I did replace the water pump and replaced the gaskets in the cap.

There are several things that can cause overheating like improper timing. 

[Lucas Feininger #15674]

I'd have to look up the receipt for the radiator, but it was probably over $500.00 including the fans, relays, wiring harnesses, etc. I did flush the block thoroughly several times but never had the time or the courage to disassemble it in order to physically clear the water passages. It is quite possible that they may be compromised.

I will say this is not some "discount" radiator. It is all welded and seems to be very well made. As far as aerodynamics go there are rubber flaps on the fan housing that open at speed to allow air flow (the fans are mounted in the back of the radiator on the engine side). My problems always occurred in stop-and-go traffic, not on the highway.

My 63 did not have a fan clutch. As far as I know those were only used on 63s with A/C, mine has no A/C. I did swap the four-blade fan for a six-blade, but that did not do much good.

I have replaced the water pump and the thermostat. I also have checked the timing and it is right on the money. For the past few years I have used a Pertronix electronic ignition module with good results.

Many drivers of older Cadillacs I have met at car shows etc. have reported no overheating problems whatsoever. Unfortunately I did have problems which I needed to address (without tearing the engine down). The aluminum radiator/electric fans solved the problem in a way that was satisfactory to me and so I simply wanted to share my experience.

Lucas Feininger
CLC #15674
1963 Series 62 convertible

[dadscad]

Lucas, thanks for sharing your experience and solution to your problem. I had a similar situation on my 63, after having the engine rebuilt. My car would over heat in traffic if I couldn't keep it moving and it would run hotter the faster I ran or if I was climbing a long grade. I used a Barber Flushing gun on the block and had a 4 row core installed on my original tanks, nothing seemed to really work. I ended up getting a brand new Heavy Duty 4 row radiator from U.S. Radiator, that radiator solved my problem, also. My car has A/C, I replaced the fan clutch, water pump and everything I could think of to keep the thing cool. The brand new radiator has kept it cool. I fought the overheating situation for years and about 50 something thousand miles. I've put about 10K or so on the new radiator with good results.



David