Radiator Trivia

[busboy]

I learned a nugget from my radiator man this morning I thought I might pass on.  My old radiator core from my '84 Eagle 10 had a 5 row-3/4" tube setup.  The new radiator core has 8 row-1/2" tube setup. 
BTW, I should be back on the road tomorrow(in Denver now) and I'll let the board know how the new radiator does...
Happy Trails,
Brent

[David Anderson]

Please do Brent.  I am agonizing over my temperature problems with my 10.  I've been trying different things for 3 years now to try to squeeze more cooling out of what I have.  So far no success.  I too have a 5 row radiator.

Note the ambient temps, location, gear you are in, etc when you record some measurements.  My problems tend to start around 3000 ft msl at temps above 95, moderate climbing at any speed above 60mph or 10psi or higher on the turbo gauge. 

Keep us informed.

David

[Burgermeister]

Brent ,

Assuming similar tube configuration and cross section, it would appear that the 8 row has about 6% more cross section and 6% more surface area than the 5 row.

On the other hand, the 1/2" tubing may have more internal resistance gobbling up the apparent "advantage".  This can best be determined with a manometer set up.

It's possible that you'll experience similar (equal)  cooling capacity to a properly maintained radiator like that removed. (Which is not my point)

With a new core (assuming everything else is also up to snuff)  continued overheating or marginal heating is an indication that you're aerating the coolant somehow, which is my point to Dave Anderson. 

Dave, 

What set up do you have in your Eagle 10?

Is your system cleaned out, etc.?  Have you upped the horsepower? Anything else (plumbed the genset into radiator system?) ?

[Brian Diehl]

How would you be able to tell if the coolant is getting aerated?

[busboy]

Just my humble observation between my old core and the new one:
1) The new ubes seem to be staggered vs the old core that looked like an Olde English Military regiment
2) The fins on the new tubes seem to be louvered vs the old one that were flat
Not sure if any of that helps but I thought I would point it out.
Happy Trails,
Brent

[David Anderson]

Dave, 

What set up do you have in your Eagle 10?

Is your system cleaned out, etc.?  Have you upped the horsepower? Anything else (plumbed the genset into radiator system?) ?

Yes, it's cleaned.  The truck radiator shop that cleaned and rodded said it looked like new, no compromise of the tubing or fins.

No, engine is an anemic 315hp

No genny, however it has the stock DD water to oil cooler and a water to oil cooler for the Voith transmission.  I may begin to suspect the tranny heat could be a problem cause in climbs.  I never thought of that before, but it definitely generates heat to the coolant.


David

[Burgermeister]

Brian,

I guess you could install a glass/plastic tube for a visual verification.

 But that will only work easy on a dyno, since the test has to be under power and at regular temp.

The easiest way I know to check is run a manometer check on the system to check pressure drop through the the heat rejection portion.

This is technical and every time I try to explain these points I catch flack, so "flack it"  I'll just have to show ya!  LOL!!!

 I'm checking into  building the apparatus now to perform this test.  If I make it to Busn'2007 with RJ Long at Arcadia this New Year's I'll bring it with me and see if I can find a willing overheat victim. 

Marc

[Burgermeister]

Checked on the question.

Radiator mfgs test cooling system resistance with air, not coolant (believe it or not,  air is more accurate)

Field test using manometer set-ups are fine.  The accuracy of air tests isn't necessary to determine whether coolant will aerate.

I'm getting a drawing sent of the proven set-up and will make one with a couple of adaptors for various installations.

Marc Bourget

[Rich (Prevost)]

The only Eagle radiator trivia I have is the phone number to the company that built the radiators for Eagle. Atlas Radiator (Larry) 361-882-5661. Corpus Christi, TX..................................Great guy.......................

Rich
800-468-5287

[busboy]

Dave,
8V71, 740 Allison, 15KW Kubota Wrico genny plumbed into bus radiator.  I had a couple of days running the generator before it went out and noted that the temp gauge did not climb over 180 from Denver thru Kansas to Missouri...there are some small climbs out there that would have sent my previous setup into the overheat zone.  Most of the time the temp gauge is below 180...175 or lower.  It was expensive by the time I bought new top/bottom tanks and side rails, plus the core, plus S&S putting it in.  I'm also running the Detroit pink 50/50 mix coolant.
Guys, what is too cool while running down the road?  170 ok?
Happy Trails,
Brent

[David Anderson]

Brent,

That is good to hear.  I'm taking my radiator to a shop Monday to upgrade to the best cooling technology available.  I'll keep you guys posted on the proposal they give me.

David

[David Anderson]

I got my results from the radiator shop in San Antonio.  My core is a 5 row 3/4" tube 32x37.5x4.5" fin area with a rated 10,000btu rejection.
They can build me a new core with 1/2" tubes 6" thick for a 11,200 btu heat rejection rating all for the nominal price of $2470.  LOL.  Darn, copper has gone up.   

I'm not sure if I want to do it this way.  I'm trying to get in touch with Tom at Dever Radiator to see what his take on it is.  I think he would have a better understanding since he builds this stuff to run in high mountain altitudes  Also, I emailed Voith USA to determine what the heat rejection is on my tranny.  It should be similar to an Allison, but I'd like to know. 

So, far, Richard's suggestion of the Hayden fans (see the thread about "auxiliary fans") is the cheapest idea. 

David

[David Anderson]

I just got off the phone with Tom at Denver Radiator and they can build a 7 row dimpled tube 12000 btu heat rejection core for me for about $1700.   I wonder if a 20% gain in efficiency is enough??

David

[busboy]

David,
I wonder why my radiator was so much more from Denver Radiator?  Is yours a different spec or size?
-Brent

[David Anderson]

I'm not sure.  I will reuse my tanks and rails, only replacing the core.  However, I may defer on this core replacement.  I had a long conversation with Gene Rochester today.  (Most of the older board followers will remember him).  Anyway, when he repowered his eagle with a 500hp 8v92, he had severe heating problems.  He finally switched to a big honking fan out of a GMC.  He remembered the  blades were twice the size of the OEM eagle fan.  He also enlarged the drive pulley to spin it faster.  It moved so much air it would suck your body up to it when you walked by. 

I later had a conversation with the owner of Texas Custom Coach.  He found a European 16 blade variable pitch composite fan that he has installed on 3 Eagles with 8-92's and solved each one's cooling problem.   Ironically, he was just ready to install one on his own bus.  This fan is about $450.  and can be obtained from Goodson Bus Sales.  I called Goodson today and will try to spec one out next Monday.  This will be much cheaper than a recored radiator and perhaps a bit better than the electric aux fans that we discussed on another thread. 

About this fan--I did talk to one guy at Bussin USA in 2005 that had it on his Eagle and was very pleased with the outcome.  I didn't see it, but it was discussed.   It seems counterintuitive that Gene's fan had less blades and more surface area, and the variable pitch fan has 16 blades.  I don't have an explanation for that. 

The fan issue and air volume was strongly emphasized by the head engineer at Atlas Radiator in Corpus Christi TX.  He noted that air volume was critical in these eagles with the 6 & 8 V92's with turbines.  It was always a problem, thus I'm leaning more that direction as a fix over fiddling with what the radiator shop told me is a fundamentally adequate radiator.

David