1/3 of the energy of the fuel goes out as heat in the exhaust
1/3 as mechanical rotational useful output (like to drive the gennie)
1/3 as heat in the coolant loop

So that at least gives you some idea of how much heat you have to shed from the coolant loop.

Finest regards,

troy

so then does that make what goes to the coolant 1492watts or 5090BTU?

I used the cast iron radiator chart in my previous post to measure the BTU output of the cast iron radiator George B tested. It came to about 5,000 btu... So I found one about the same. But even George B. is saying on the same web page that theres about 20,000 btus to shed inthe coolant heat. So what I'm trying to figure is it 15-20k or is it 15-20k divided by 3...

Mike

I calculate a 50% loaded 6 HP Listeroid dumps about 15,000 BTU/hr into the cooling water.  According to a table in Marks Handbook, heat transfer from bare oxidized steel plate is about 2.2 BTU/degree F-hr-sq-ft. 

So, let’s say we had a tank measuring 16 inches in diameter, and 4 feet high.  It’d have about 17 sq-ft of surface area.  If we allowed it to get to 210 degrees F on a hot day, say 90 degrees F, the heat lost would work out this way:

(210-90)*17*2.2 = 4500 BTU/hr.

SO can I use that formula for the cast iron radiator I figured to use?

 Its a "tube type" 23"tall, 4 tube thick, and 7 sections.

Heres a cast iron radiator sizing chart: http://www.colonialsupply.com/resources/radiator3.htm
you can back up a page for more info.

According to the chart I have 17.5 EDR (equivalent direct radiation),and with your formula: 17.5 x 210-90 deg F. x 2.2= 4,620btu/h
if Im understanding it all correctly. 

This chart is for sizing the radiators in an enclosed room. I wonder how this can translate for our purposes....

I know the engine itself gives off heat and I figured I'd add a temp controlled fan to the radiator. So how to I calculate those two factors?

Mike

mikeptag,
Welcome aboard. Alot of information available here. What are you using your engine for? Did you deal direct with India or is there an importer in the the  US.

Thank You. Glad to stray into here. I will be posting photos as I work on the engine. As it is now photos are in Coppermine, link in my profile.
I will be hooking it to an ST Head. Perhaps I will directdrive it to a WOODMASTER, 4-in-1 Planer/Molder/Sander/RipSaw...I got the engine and Generator from George B. It seems to be well made as I look it over, but I am putting all new fuel lines, fuel filter, tank. I have a radiator and fan  for cooling for now, later I'll figure a way to utilize the heat.

Mike