|
|
Veteran
Location: Kingsley Michigan | Anyone interested in how we got here should review the threads involving the moving of the radiator by Stephan Heinrichs.
I have calculated all of the unknowns of the present 440 radiator fan to be .55 cubic feet per revolution. This number times your rpm's will get you the total cubic feet per minute needed for your system with proper placement of the oversize Robert Shaw thermostat. As always in engineering such a project, error to the high side to prevent surprizes. Also, safety factors should be included in your thinking.
Happy Holidays to all: Barney  |
|
| |
|
Veteran
Location: Illinois |
Barney - Have you included in your calculations the Fan Pulley RPM relative to the Crank Pulley RPM???
Give me a call, 800.786.1536 - 8 to 5 central time, as I have question for YOU concerning prior parts order.
MERRY CHRISTMAS - Leslie Hoagland |
|
| |
|
Veteran
Location: Kingsley Michigan | Yes Les, I did compensate for the 15.4% difference in the diameters of the fan pulley versus the crankshaft. I also purposedly errored on the high side of all of the calculations to give the old system the maximum benefit of possible output so as not to under size any modified system.
While my cooling system works fine now, Mr. Heinrichs has got me thinking about that whole engine room heat and noise thing as Mr.Jacoby did with his hinged radiator grill. I will do the conversion using some puller type Procomp fans mounted on the exterior of the radiator. As far as I have found, 4 - 10", 1250 cfm, 8 amp fans would be considered a overkill by 25% but OK-- One fan will run constantly while the engine is on and for a minute or 2 after it is shut off. The rest of the gang will have staged on temps and all will have manual overides controled from the engine room to make routine oil and other inspections on the road a more pleasant detail. Also the electric fans will not impose an unnecessary (during warm up) and immediate load on the engine as the mechanical one does, to speak nothing of elongating the life of the water pump.
This might help the whole engine room noise and heat and cleaning of the radiator a lot less painfull. Lets face it, modern technology and materials can be of great benefit to our old designs and at the end of the day---an engine overheating is the ultimate resposibilty of the nut that is loose behind the wheel
Merry Christmas; Barn |
|
| |
|
Veteran
Location: Illinois | Barn -
The reason for my question is that your CFM calculation seems low as the amount of air coming out of the radiator with proper setup of fan to shroud and engine belts seems to be so much more at idle or reving engine to 3000 RPM than from the 2850 CFM fans that we mount on the passenger engine grille. This fact is comparative to be certain, BUT the engine pusher fan has to have CONSIDERABLE CFM since the rear engine pusher fan design has minimum RAM AIR EFFECT.
It will be interesting if you can mount lights to show which fans are functioning. This will indicate if the volume of air is sufficient at what speed - 50,60,70,80 MPH which will change, obiviously - with GCW, grade percent, wind speed/direction, and ambient temperature.
Also there is no denying that to hinge the radiator grille would be great, as we have done this on several customers coaches over the years; and I am going to do this to my coach when we complete some structural improvements at 400,000 miles after the first of the year.
In the distant past, we even spoke of gimbaling the radiator for acess to the engine from the rear. BUT we canceled that idea due to the many NEGATIVES.
Looking forward to your report when installation is completed.
HAPPY TRAILS - Leslie |
|
| |
|
Veteran
Location: Kingsley Michigan | Hey Les--you know what the sad part about this all is---the guy who helped me pull the engine out of my coach (for rebuilding), has a CFM meter as he works with refrigeration units but he forgot to bring it over the day he came over. Maybe someone else will volunteer their coach for tests and I will borrow the meter---maybe at a rally or something---
Barn |
|
| |
Our old radiator cooling change