LV3 being modded

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mcrae0104

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Oct 27, 2009
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BJC
I could respond to your post above but I don't think you would listen based on the way you've treated others around here, so I won't. Good luck with your project.
 

TarDevil

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Jun 29, 2010
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Coastal North Carolina/USA
Someone on the internet said:

"It must be said that many experimental aircraft have had relatively inefficient radiator setups and consequent cooling problems"

"Most power losses are attributed to problems with the supporting systems, not the core engine. This is where careful design decisions pay benefits and poor practices often cause engine shutdowns."

"Shared information on various forums and learning from both good and bad experiences will result in better designs which should improve overall reliability."

http://www.sdsefi.com/air51.htm
It's encouraging to see you are gleaning information from credible sources!
 

pfarber

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Feb 21, 2019
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It's encouraging to see you are gleaning information from credible sources!
I've done nothing but echo those exact some concerns.

So I find a great possible solution that's never been tried: its lighter, performs better and uses less engine power.

Spend the next few weeks playing wack-a-mole with every less than informed opinion from people who have nothing significant to add.

Sprinkle on a personal attack or two because 'Internet courage' is a thing.

To date no one has even posted anything close to a credible reason not to try it.

I wonder if the author of those words would like to point out where I have made an error??
 

mm4440

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Jan 14, 2012
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LA area, CA
Hi, as has been mentioned, ground cooling problems are typically caused by low airflow through the heat exchanger not low coolant flow. My suggestion of an electric pump in series with an underdriven belt drive pump is for redundancy. An additional heat exchanger with an electrically driven fan can provide additional ground engine cooling and double as a cabin heater. The early Ford V-6 conversions had cooling (and other) problems. Fred Geshwender, an auto engine conversion pioneer, discovered that the stock water pump was crap at moving water and replaced it with a SVO racing water pump. No more cooling problems. That is the only coolant side problem that I have heard of. I had a cooling fan thermal switch fail while I was stuck in stop and go at LAX and the needle was headed to HOT. I opened the windows ahd set the heater on max and max fan and the needle stabilized while I got out of the airport and got some ram air flow through the radiator.
 

pfarber

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Feb 21, 2019
Messages
486
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Pennsylvania
Hi, as has been mentioned, ground cooling problems are typically caused by low airflow through the heat exchanger not low coolant flow. My suggestion of an electric pump in series with an underdriven belt drive pump is for redundancy. An additional heat exchanger with an electrically driven fan can provide additional ground engine cooling and double as a cabin heater. The early Ford V-6 conversions had cooling (and other) problems. Fred Geshwender, an auto engine conversion pioneer, discovered that the stock water pump was crap at moving water and replaced it with a SVO racing water pump. No more cooling problems. That is the only coolant side problem that I have heard of. I had a cooling fan thermal switch fail while I was stuck in stop and go at LAX and the needle was headed to HOT. I opened the windows ahd set the heater on max and max fan and the needle stabilized while I got out of the airport and got some ram air flow through the radiator.
I posted an article from Contact! magazine that used the same airframe I have (BD-4B) and a Ford V6. He used a belly mount radiator and noted cooling problems on taxi.

http://www.contactmagazine.com/Hangar_Talk/August-08/John_Steere.html

"However, there have been times on hot days, during long climb outs, that the thicker radiator may have been beneficial. " Its noted in other articles that he solved his taxi issue with the addition of a radiator cooling fan. (article from Experimental Aviation Technology Magazine, April, 2005) This article is much more detailed regarding the build.

I agree that the radiator must be properly sized and with sufficient airflow.. but the rules of thumb he used are echoed in many other articles.

There is another BD-4B with a V8 (a custom race engine) and he noted overheating on taxi. He said he just killed the motor. Not an option I like.

My thought process revolves around to critical areas of the design: proper radiator size and proper coolant flow. Its just a fact that at idle the mechanical water pump simply doesn't move enough coolant. Yes, you COULD have an over sized radiator, but for efficiency at cruise I must keep the radiator drag to a minimum. Making a larger radiator or exposing it to more air increases drag and weight just to solve the taxi issue.

I believe that an electric water pump would solve this issue with a 'cruise' sized radiator. Under size pulleys do the exact opposite.. they reduce coolant flow even more. I'm not really worried about dropping 5hp, but I am concerned about overheating, especially at climb out/taxi.
 
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