Cooling Problem Solved!

[Bluemalibu]

   Accepting change sometimes comes slow for us dinosaurs. 

 

   For the last eighteen to twenty years, I have been a die-hard fan of the two-speed Lincoln Mark VIII electric cooling fan.  I have used it in combination with the largest Griffin or Champion aluminum radiator that I can stuff between the frame rails of a car, and have never been disappointed in dozens of builds.      Until now.

 

 

   The '72 had dual Flex-a-Lite fans mounted when I bought it.  While the Mark VIII swap saw an improvement in temps, I have been unable to adequately manage the cooling of the 504 ci engine.   We are told that 80% of a fuel's energy is converted into heat.   The 504 eats fuel at the rate of 4 miles per gallon.  That is a lot of BTUs to deal with.    The above combination of parts has only managed to keep the temps at 225* in city stop-and-go driving,  and at 210* in highway driving during 105* days.   While I have never experienced a boil-over,  I keep anticipating that I am always just five minutes away from an overheating emergency. 

 

  As Hot August Nights hits this week, with its 4-hour nightly cruise, I knew that I needed to solve this problem before I headed out to the show.

 

  Because the Mark VIII and aluminum radiator have always worked in the past, I began by addressing other possible  causes of the high temps... such as over lean mixtures, retarded timing,  etc.      No luck there.

 

  My next step was to remove the Caterpillar heat exchanger from the lower radiator hose that cooled the 4L80E.

 

 

 

   While this exchanger fit perfectly between the radiator and water pump, and provided the proper 1 1/2" connections,  I was afraid that it was creating a coolant restriction due to the elevated highway temperatures.    With its removal, I only saw a six degree improvement.   So, I looked deeper.

 

   My guess was that a 2" x 19" gap along the sides of the radiator was allowing the incoming air to bypass the radiator at highway speeds, and that the 70-75% coverage provided by the Mark VIII was insufficient to cool the circulating coolant.

 

   So,  I  pulled the fan assembly off of the car;

 

 

 

 

 

   And I began a serious search for the best fan available today.

 

  What I settled upon, is the dual fan setup for the 2013 Ford  F150.    This unit would provide full radiator coverage, while increasing CFM's by nearly a thousand.  I found one at a yard in Idaho for $50, and had it flown to me for an additional $20.

 

 After cutting ports for both upper and lower hoses, blocking the bypassing air with one-inch thick closed cell padding, rewiring for a dual fan assembly and engineering new mounts, here's what fitment looked like at 3:45am this morning:

 

 

 

 

 

 

    The acid test today involved thirty minutes of highway driving,  followed by forty minutes of stop-and-go city driving,  and then another half-hour on the freeway...  all completed during the 1 to 3pm heat of Northern Calif.

 

   Success!!!    At no time did the car climb above 178*       I am one happy camper.

 

     Doug

[dbreese]

Nice writeup Doug!! Glad you were able figure out the issue. 

 

David

[Bluemalibu]

  Thanks so much, David...

 

    I might have guessed that it would be another fellow enthusiast with a long history of Arrest Report writing, that would take notice.   LOL!!!

 

   Doug

[dbreese]

  Thanks so much, David...

 

    I might have guessed that it would be another fellow enthusiast with a long history of Arrest Report writing, that would take notice.   LOL!!!

 

   Doug

 

Yep, have written just a few. 

Out of curiosity what type relays did you use and what kind of temp control module?

 

TIA.

 

David 

 

David

[Bluemalibu]

 

Out of curiosity what type relays did you use and what kind of temp control module?

 

    Regular 30 amp automotive relays (plastic) won't hold up to the demands of these fans over the long term; as they briefly draw about 80 amps at start-up.  

 

   I used a Bosch 180 amp Continuous Duty solenoid on each fan.    http://www.amazon.com/BOSCH-TERMINAL-CONTINUOUS-SOLENOID-1987be2001/dp/B00FGJIX2M

 

  Finditparts.com carries them for $32 each.

 

  Ultimately, I will install a PWM soft start controller to cushion the demand on the circuitry at start-up...  but the current batch available have a hit-and-miss track record so far for dependability, so I am using a Dakota Digital dual-fan controller for the time being.       http://www.summitracing.com/parts/dak-pac-2750

 

  Doug

[dbreese]

That Dakota Digital controller is pretty slick! One day I may get rid of my old antiquated mechanical setup and go electric. LOL

 

David

[LS65Speed]

Doug

 

Do you have any details like the  P/N for the fan?  Can I assume that the same elections (alt) support the new fans? I have the CS130 and it works fine with my Mark VIII  fan. Wondering what you are running for an alternator. Have you checked the start-up draw of those fans from the 150?

 

Ray

[stangeba]

Great write up and information, thank you!

[Bluemalibu]

  Thanks so much, Bruce.

 

  Ray,  I too had a CS130 with the Mark VIII, but the F150 draws nearly double the amperage.  (Which coincides with the increased cooling capacity) So, I replaced the CS130 with a chrome AD244 that is pictured above.  The CS130's design only produces about 20 amps at normal cruising rpms of 1400 to 1800... even though it is advertised to be rated at  60 to 120 amps.  The AD244 will put out over 100 amps at 1500 rpm (Up to 240 amps at higher RPM)  and will produce 60 amps at idle.

 

   Patrick and I cruised Paso Robles for an hour  last night with the car idling the entire time.  I kept the dual fans energized along with the 145 watt Flosser headlights, and the voltage never dropped below 14.2. 

 

  At start-up, there is a very brief spike of about 85 amps... which quickly settles to about 20 amps.  A soft-start DC controller would alleviate this.

 

  The Motorcraft number is AL3Z8C607A.                   Doug