aluminum radiators

[Tom B.]

Re: Coolant flow requirements (Show-stopper)

Duke,

I can hear the groans already. It would appear that's some supportive information that I was hoping for --- at one time (and it seems like only yesterday). I was experiencing higher running temps at higher (highway) RPM's for my 68 BB (with 4:11). The recommendation given to me (by a long time racer and owner of (many) Corvettes) was to use a simple $7.00 flow restrictor-kit in place of the thermostat - for that problem / application. Eventually that helped spark the heat transfer debate of yore, everyone started looking for black and white answers in a gray area, and the rest is history. Thanks, (and please don't say I've jumped the gun). TBarr #24014

[Jack H.]

Re: Coolant flow requirements

Don't think it's a gradient issue.... Cavitation creates thermal curl, resulting in localized negative temperature divergence spheres. Read this hot spot bubbles that migrate. But, how can a simple EE read on ME's advanced thermo teachings?

[Robert C.]

Re: aluminum radiators

Jack, Don't the newer Corvettes run at higher operating temps because they're supposed to? A local Vette owner /engineer called , and got, one of the Corvette engineers in Bolling Green and asked; Why doesn't my electric fan come on at a lower temp, instead of 230, say 210 or 200? The engineer replyed," We got to many complaints from woman, scared of the sound of the fan comming on, thinking the car was overheating". They also said that the electric fans were so cheap that they would wear out to quickly if they came on to often! Believe me GM is listening!

[Dave Wrzesinski #24235]

Re My favorite subject - thanks for the astute obs

A little thermo - a little transport process - a little cost analysis... sounds like an engineer to me. Thanks for the astute analysis. Sure beats a little eye of newt - a little ear of bat.... that you get in aftermarket radiator adds written by marketing people. - Dave

[Duke W.]

Cooling system issues

Anyone who has a long term relationship with a vintage car, Corvette or otherwise, will eventually have cooling system problems. The first noticable symptom is usually a higher operating temperature. Then all the "fixes" begin - snake oil coolant additives, remove the thermostat (big mistake), replace the thermostat with a restrictor, finally go out and pay big bucks for an "oversized" radiator that forces you to cobble up the car to install.

A lot of knowledgable, talented, and thoughtful people designed and developed the cooling system in our Corvettes, but like all the other systems and components, cooling system performance slowly and insidiously degrades until we notice there is a problem. The best thing to do is restore the original system to its design performance. A big culprit in cooling system problems over the last quarter century has been silicates in our anti-freeze. They provided excellent corrosion protection, particularly for aluminum, but the down side is that silicates, along with the other inorganic salts designed to prevent corrosion, slowly clog the system, particularly the narrow passages in the radiator, so the real fix is to restore the radiator, or more properly, the heat exchanger to its as original as designed heat transfer performance.

Unfortunately, if you have an aluminum radiator, it is probably not reparable, so I'd recommend biting the bullet and buying the repro to insure that you restore original performance. If you have a copper/brass radiator it may be reparable by the "rod out" process, or you can have it recored. Then I would protect the new investment with Havoline Extended Life anti-freeze (GM Dexcool) mixed 50/50 with distilled water. I've researched Dexcool thoroughly and everything I have found supports the conclusion that Dexcool provides superior corrosion protection, particularly for aluminum, yet has no silicates (or other inorganic salts) that ultimately clog the system and abrade the coolant pump seal. Of course, there can always be other problems, such as fan performance or malfunctions in the ignition advance (centrifugal and/or vacuum), so a thorough check of all related systems should always be accomplished. If all related systems are in good working order and cooling system performance is "near new" then overheating should not be any more of a problem than when our cars were new, but it's no secret that the big block sharks had little margin.

The nice thing about this, Tom, is that with the money you save you can get into VSOP and Davidoffs, but from the sound of Jack's last post, he's already discovered them.

Duke

[Jack H.]

WOW!

Original pre-litigation Cuban Davidoff's.... My mind wanders to the 'good ole days'! They're still out there being preserved in humidors around the world + the interum Davidoff's rolled in Belgium are a nice rare find when you stumble across 'em too.

As far as VSOP, have you tried the limited Millenium bottling of Couviessier? You can still find bottles on retailer shelves here/there rather inexpensively. But, ole Uncle Jack REALLY like to curl his fingers around a snifter of Hennesy Paradis or Louis XIII when total relaxation is the order of the evening!

[Duke W.]

Jack,...

thanks for the tip. I don't have a favorite brand, but my "holiday bottle" is nearly empty. It's nice to know that you are both a scholar AND a gentleman.

Salute

[Bill Braun]

Jack, would you mind..

sticking with English, please?

Bill Braun 33186

[alan johnson]

Re: My favorite subject -- heat transfer/field the

Thanks very much to Joe and others for the great info -- yes, I checked out DeWitt's site -- My wife suspects they may get some business soon. Thanks also to Jack for scratching my engineer's itch!

[Jack H.]

Re: Jack, would you mind..

UJ could be going looney tunes, but believes all words used in posts CAN be found in Webster's and are accurate descriptors to the best of his ability. Seriously, the Jay-Walking sequence of Friday night's Tonight Show featured Jay Leno asserting the average 14-year old had a 14,000 word vocabulary in 1975 and has a 10,000 word vocabulary today. He tested this (in typical Jay Leno biased cut the out takes I don't want to show fashion) and much was humorous.

It's refreshing to visit England and view the news there. Announcers do NOT talk down to the 4th grade 'fog factor' that ours do. I find myself screaming sometimes viewing US newscasts when I see highly paid, college educated, anchors boiling the spot SO FAR DOWN that the dilution affects content and winds up mis-reporting events....

[Duke W.]

Jack...

quit watching the news (except for Jim Lehrer and Jay). Watching the "news" places one in danger of being tranformed into another lowest-common-denominator blob of protoplasm.

Duke

[Bill Braun]

Re: Jack, would you mind..

Well, uh, sure, but then, uh, you know, that Webster is like, uh, sorta a big book, and, uh, well, sometimes, uh, well, like kinda hard to read, you know, and like, even though, I sorta like, uh went to a like, good college? you know, we uh, never really had the, uh, opportunity to like deal with, like thermal curl, you know? Not.

Ya gotta love these technical discussions, right? All in fun, boys...

Bill Braun (Um, like 33186)

[Jerry Clark]

Re: Jack, would you mind..

Personally Bill and myself would have a awesome time, ya know, ya hear what I'm sayin ?

jer