"Aluminum radiators are no good"...???

S

Sawbones

Junior Member
This is what I was told by someone who ought to be in the know. I'm building my first Flathead and I'm about ready to fire it up. There's a lot of odd things about this engine compared to a more modern V-8 and I didn't want to screw up. So instead of buying a Champion, I bought a used original radiator as it was the best I could afford in non-aluminum. It didn't seem right that all aluminum radiators are garbage, but maybe the guy knew something I didn't. Well, turns out the radiator I bought isn't that great. It ought to hold me for some bench running but I'd never want to take it down the road. I asked the guy why he was so against aluminum and he came back with electrolysis, flex cracking, and poor build quality. I figure electrolysis would be taken care of with proper coolant and maintenance and rubber isolator mounts. The rubber isolator mounts would probably deal with the flex cracking too. The poor build quality, I'd try to get a decent one and hopefully that wouldn't be an issue. Nope, HAS to be Walker or Brassworks. For real? We're pretty much all of us running aluminum radiators in our vehicles anymore. Does anyone on here have a dang concrete reason why I shouldn't go with a Champion radiator for my 8BA? I can't shell out $800-$100 as much as I'd love copper.
 
Opinions of aluminum versus copper are all over the place. I have an expensive copper Brassworks radiator in my '39 p/u BUT that isn't to say that aluminum radiators are junk. There are many many posts over on the HAMB regarding aluminum radiators cooling blown big blocks with no issues. My thought is that whatever route you decide on go with a quality brand. I've never heard anything bad about Champion but then again I've never owned one. I did buy an aluminum radiator off the internet for my '54 Ranch Wagon project because I need one in a hurry for the 302/AOD mock up. Can't say how it will cool since its not running yet but it fit perfectly and the quality seems good. And welcome aboard.
 
There have been aluminum radiators in Corvettes since the 1960s...factory equipment. They are fine if you have a quality built one.
My humble opinion..
 
After the original radiator in my '46 59AB couldn't be rebuilt (so said the shop), I bought a Champion. It has performed flawlessly. Zero issues. At the time, I faced the same dollar difference and couldn't justify 3X the cost for a driver restoration.

Buy the unit you believe is the best solution and thank others kindly for their opinions.
 
I purchased a champion radiator for my 50 cpe 14 years ago filled it with the good old yellow preston coolant with distilled water 50/50 mix i’ve had 0 problems the inside looks like the day i assembled it my son has restored 3 collector vehicles in the last 6 years with these radiators also with 0 problems good luck
 
I put a high-quality aluminum radiator in my 1965 GTO.
The one I installed has stamped top and bottom tanks and I painted it with a light coat of self-etching black primer. Now it looks like an original Harrison unit.
If you think flatheads run hot, try a hipo Pontiac. Yikes.
Also installed the proper fan shroud and fan along with it.
It's still a blast furnace when you open the hood but no more overheating.
 
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Running an aluminum radiator in my 34 with no issues for ten years. Ditto my 30 roadster for the last four.
 
Like anything, you get what you pay for. A cheap Speedway fits-all aluminum radiator won't be as good as an expensive Griffin. My Avatar car which made its maiden run on the highway after sitting in the rain since 1949 has a Griffin radiator that I installed in 2000. It cools so efficiently, with no thermostats it wouldn't get above 110 degrees and ran terribly. Put in 170 degree stats and it warms right up and never gets above 190. So this aluminum radiator is 22 years old and has 7k miles on it with absolutely no problem. It wasn't cheap, I think it was $750 back in 2000. I don't even try to drive the car until the temp gets above 150, then it is sweet. This i my experience with an aluminum radiator and a flathead.
 
I've never had an aluminum radiator in any of my flatheads but did install one in my 81 GMC pickup. A "Spectro" I think was the manufacturer. Its been good but my one complaint is that I can't solder repair it when it gets damage to the core. And wouldn't you know within the first thousand miles I got a stone bruise right in the middle that started it leaking. JB Weld to the rescue and its been good but I'd feel safer with solder.
 
[FONT=&quot]I have aluminum radiators in all three of my old Fords, two of which I put in myself to replace the original units...but not because I feel aluminum is the better option. I couldn't find a local person I could trust to recore the originals decently, among other considerations. All three cars have worked fine with aluminum cooling. However, here are two things I would suggest if you replace the original radiator with aluminum:[/FONT]

[FONT=&quot]1- Keep the original radiator, no matter how poorly it's working. Some potential buyers of your car down the road may insist on a copper unit. [/FONT]

[FONT=&quot]2- Install a zinc anode in your cooling system. A lot of people don't do this, but it apparently helps reduce any corrosion that might happen because of dissimilar metals. Kind of a theoretical solution to a theoretical problem, but I figure it can't hurt. [/FONT]
 
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JimNNN said:
[FONT=&quot]I have aluminum radiators in all three of my old Fords, two of which I put in myself to replace the original units...but not because I feel aluminum is the better option. I couldn't find a local person I could trust to recore the originals decently, among other considerations. All three cars have worked fine with aluminum cooling. However, here are two things I would suggest if you replace the original radiator with aluminum:[/FONT]

[FONT=&quot]1- Keep the original radiator, no matter how poorly it's working. Some potential buyers of your car down the road may insist on a copper unit. [/FONT]

[FONT=&quot]2- Install a zinc anode in your cooling system. A lot of people don't do this, but it apparently helps reduce any corrosion that might happen because of dissimilar metals. Kind of a theoretical solution to a theoretical problem, but I figure it can't hurt. [/FONT]
Click to expand...

I have always been an advocate of anodes in cooling systems for engines with mixed metals. However, if you are going to go to the effort to use an anode, magnesium is a better choice to use with aluminum than zinc. Zinc is quite close to aluminum in the Galvanic Table, so it doesn't protect as well as magnesium. Magnesium anodes are available, but an easier cheaper route to go is to use RV water heater anodes, readily available on Amazon.
 
I tried a Champion in my '41 coupe. It would overheat quickly in traffic, and over 60 on the highway, on any 90+ day. That was with timing advanced, Dennis Carpenter water pumps (improved flow), water wetter, and baffles to direct more air flow through the radiator. The engine is 284" with a Schneider 248f cam and compression near 9:1. The block was thoroughly cleaned out during rebuild. I was able to fix the 01T truck radiator that the car came with, and that keeps it cool. The other thing that helped is running a much lower concentration of antifreeze. I think my problem was largely the boosted engine power, and the fact that I could not bring myself to put in an electric fan to remedy the poor air movement power of the low crank mounted fan in my '41..
The Champion aluminum radiator should be fine on a stock engine.
 
I think the biggest difference is going to be fully welded versus glued. The glued radiators are the ones that typically fail, not the fully welded radiators. It’s much quicker to glue the core to the tanks versus welding so watch out for the cheaply priced aluminum radiators since they are typically the glued type. With that said, I’ve never had any issues with good quality, fully welded aluminum radiators. I still prefer brass on early restorations though.
 
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tubman said:
I have always been an advocate of anodes in cooling systems for engines with mixed metals. However, if you are going to go to the effort to use an anode, magnesium is a better choice to use with aluminum than zinc. Zinc is quite close to aluminum in the Galvanic Table, so it doesn't protect as well as magnesium. Magnesium anodes are available, but an easier cheaper route to go is to use RV water heater anodes, readily available on Amazon.
Click to expand...




Thanks for the education tubman. I knew I should've taken chemistry in high school! :)
 
Wizard Radiator in West Falls N.Y.....5 minutes from me....builds rads for everyone in

Western N.Y. as well far far away. Wizard is a small efficient operation, all disaplines
are there from design to shipping. The cad guy will scan your odd ball rad and have a

print ready for the shop . On the other side of the wall in the boss office is the welding equipment.
Charlie ny
 
Charlie ny said:
Wizard Radiator in West Falls N.Y.....5 minutes from me....builds rads for everyone in

Western N.Y. as well far far away. Wizard is a small efficient operation, all disaplines
are there from design to shipping. The cad guy will scan your odd ball rad and have a

print ready for the shop . On the other side of the wall in the boss office is the welding equipment.
Charlie ny
Click to expand...

X2 what Charlie said. We use the Wizard rads in our circle track cars
If and when my flattie needs one, it will be a Wizard.
 
Is that anode just in there hanging on a string or what? After 4 or 5 years I still really like my Champion radiator.
 
I solder one end of a short piece on #10 wire to the rivet head (?) in the middle of the sealing disc with an eye terminal on the other. I tap the chunk of of magnesium anode with a #10 tap and use a short screw through the eye terminal into the anode chunk.

The electrical circuit has to be complete through the cars ground system to work. A weak electrical current has to flow from the anode (magnesium chunk) to the cathode (iron block). This erodes the magnesium anode rather than the aluminum radiator (and in some cases, heads).
 
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