I'm almost embarrassed to ask this question but I'm a ferrous metallurgist and not an aluminum metallurgist--Has anyone experienced or heard of the aluminum radiator tubes shrinking/collapsing thereby restricting flow and causing my car to run hot? My mechanic gave this as a reason after replacing an out-of-warranty year old aftermarket radiator that he installed in my '91 350 with the appropriate Behr radiator. Car does not run hot anymore. I think I was handed a line.

Boy. That's new one on me! The only way I can think this would happen is when the aluminum begins to corrode, it could clog up the inside of the tubes and restrict coolant flow. I don't like aluminum radiators myself and went for an aftermarket copper and brass model.

New one to me as well. Tubes eaten away due to electrolysis is what
I've seen. Maybe plugged from contamination. But I havent seen one shrink.

i agree. it sounds funny.

a year old rad unless plugged with other debris should not fail.

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Thanks, guys, for not laughing. When I suggested that I could understand clogging even in a year old radiator, he still insisted that they "shrank" ! Go figure.

Open your hood and see if he left his crack pipe under there.

I would assume he meant that the flow passages "shrank" do to corrosion build-up within the tubes, not that the tubes themselves shrank. It sounds like replacing the radiator fixed your problem. Are you using the correct coolant?

If you mean Green or Pink--it's Green. But, I'm open to recommendations/name brands, etc.

Look,

Most mechanic's didn't take chemistry in High school- don't be rough on them for their explanation or lack of physical understanding!! I'd expect a discount on the Behr since he put the "shrinking radiator"in your car. What is he doing putting cheap low quality parts in your car?

You might want to find out what current dealership MSRP is for the radiator. Some independent's use a list price which is arbitrary from their supplier. In my few instances, they have reduced their price to match Mercedes benz on the bill.

Correct fluid is not green or pink. I'm told car quest carries it or can order the coolant approved for a benz. Sounds more like mixing coolant can create a reaction (chemical) assuming it had the correct stuff before. The mb stuff is buffered so the PH is neutral for basically the 2 year coolant life. That's what I've been told by the chemist (Stu), but never verified with litmus paper.

Make sure it is rinsed a few times to remove the green before putting the new stuff in.

Michael

__________________
Michael McGuire
83 300d
01 vw A4 TDI
66 Chevy Corsa
68 GMC V6 w/oD
86 300E