Home made fan shroud.

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Cope

Cope

Fusing with fire
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Made this today to try and bring down my temp. It seems to help.
 
Nice job...but, paint it black and it will run even cooler. Black radiates heat out while white reflects it back.
 
You are blocking a LOT of that radiator from getting air flow. All it can see is right through the fan opening. That ain't enough.
 
The shroud is 1/2 inch off the fins, sealed on the top, bottom and side tanks. I can feel it pulling air from the right hand side .
 
Cope said:
The shroud is 1/2 inch off the fins, sealed on the top, bottom and side tanks. I can feel it pulling air from the right hand side .
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I agree w/ rrr . I just finished reworking a single 16" shroud for two 14" fans. I painted it black to make it look better ! I used an alum. spoolgun to weld it, hard to make look good on that thin a metal. Got to finish wiring all 3 fans today . (two pullers/1 pusher)
 
Put some holes in the shroud and cover them with rubber flaps. So when the fan comes on, the flaps close and air is pulled through the fan, when driving down the road, the air pushes the flaps open and is able to escape thus cooling the coolant.
 
RichB said:
Nice job...but, paint it black and it will run even cooler. Black radiates heat out while white reflects it back.
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You are not really serious are you? Paint will just holds heat in, on the shroud probably won't make much of a difference either way but on the radiator, it would just make it worse.
 
5.7 hemi said:
Put some holes in the shroud and cover them with rubber flaps. So when the fan comes on, the flaps close and air is pulled through the fan, when driving down the road, the air pushes the flaps open and is able to escape thus cooling the coolant.
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Good Idea, or you could just add 2 smaller fans.
 
Agreed. Now if you insist on running a single fan, gotta use a 2 speed fan.
 
trapster said:
You are not really serious are you? Paint will just holds heat in, on the shroud probably won't make much of a difference either way but on the radiator, it would just make it worse.
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They call it a radiator because it RADIATES heat. There is a big difference in the amount of radiation based on color and temperature difference. Paint conducts heat and then radiates it from its surface depending on its color. If air is hotter than the surface, a black color then absorbs the heat while a white color reflects more heat.
 
RichB said:
They call it a radiator because it RADIATES heat. There is a big difference in the amount of radiation based on color and temperature difference. Paint conducts heat and then radiates it from its surface depending on its color. If air is hotter than the surface, a black color then absorbs the heat while a white color reflects more heat and absorbs less..
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I agree that the color of the shroud won't make much difference. The color of the tadiator would.
 
RichB said:
I agree that the color of the shroud won't make much difference. The color of the tadiator would.
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Got it done, w/ eception of the rubber flaps. I bought two flaps from jegs, man those things are flimsy! I`m going to drive it some before I put them in, kinda tired of messing w/ it. I spent an unreal amount of time wiring the fans up, they were designed to wire up diff. than the pusher I had in front. I had to run two diff ground set ups, because of the fast 2.0 fuel inj. controlling the fans, and I made a mistake and followed the directions that came w/ the dual fans. Took my dumbass forever to figure out! I hope they`ll keep it cool, it would be nice to run a full size filter instead of a shorty. I only painted the out side(engine side) flat black, inside is still alum..
putting two 14" fans in a universal 16" fan shroud and making them fit on a 22x19" core took a lot of fitting..-more to come----
 
RichB said:
They call it a radiator because it RADIATES heat. There is a big difference in the amount of radiation based on color and temperature difference. Paint conducts heat and then radiates it from its surface depending on its color. If air is hotter than the surface, a black color then absorbs the heat while a white color reflects more heat.
Click to expand...

So what you are saying is that in a pitch black environment, where color has no effect on anything, something painted black will radiate heat more than something painted white.
I think you are think of surfaces radiating heat from the sun, not surfaces radiating heat from within.
 
The flaps are thin so when moving they allow the air to pass on through without much resistance.
 
famous bob said:
I agree w/ rrr . I just finished reworking a single 16" shroud for two 14" fans. I painted it black to make it look better ! I used an alum. spoolgun to weld it, hard to make look good on that thin a metal. Got to finish wiring all 3 fans today . (two pullers/1 pusher)
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I swear I was talking about this on another thread just yesterday. But I didn't weld my homemade shroud I use the right stuff. Underneath the paint it looks like it's been welded but it's actually just Permatex. It's been on there for two and a half going on three years and looks perfect. Any kind of welding is completely unnecessary.
 
Every Spring we go thru a buncha cool rads/elec fans/ exotic shrouds that mostly overheat. Do yourself a favor, and search "overheat" to see a vast array of imaginative, exotic designs that didn't work, and the few that did . Cheers
 
j par said:
I swear I was talking about this on another thread just yesterday. But I didn't weld my homemade shroud I use the right stuff. Underneath the paint it looks like it's been welded but it's actually just Permatex. It's been on there for two and a half going on three years and looks perfect. Any kind of welding is completely unnecessary.
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I had the alum. shroud, I had a spool gun that I`ve never used, u think I`m not going to try it ?!
Get real !
Wired up a by pass today , to spin the new fans after shut down ,in case I get a wild hair and finally go to the dragstrip.
I have exactly 1/4" inch between the closest place on the upper offset 14" fan and the water pump bolts. I do have room for a full reg. size oil filter now . The new fans seem to be moving more air than the fixed belt driven fan at idle. Drive tomorrow------------------
 
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This is just a one piece of aluminum that I had from a sign company that I did some scrap metal work for. I took it and cut it to the correct size adding an inch each way and then bended the edges all the way around and again Permatex it all the way around. The Right Stuff Permatex held now for a couple of few years nicely and shows no signs of peeling or where.
IMG_20180402_180807.jpg
 
j par said:
This is just a one piece of aluminum that I had from a sign company that I did some scrap metal work for. I took it and cut it to the correct size adding an inch each way and then bended the edges all the way around and again Permatex it all the way around. The Right Stuff Permatex held now for a couple of few years nicely and shows no signs of peeling or where.View attachment 1715169746
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looks as good as mine! my fans are staggard up and down, the lower one hangs over the edge of the rad. and shroud on the pass side and the bottom. Had to build the offsets on the outside of the shroud so it would pull air thru the rad. only.
 
trapster said:
You are not really serious are you? Paint will just holds heat in, on the shroud probably won't make much of a difference either way but on the radiator, it would just make it worse.
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Guess that's why Chrysler painted all their rad. black huh ? Along w/ gm. ford, and all the foreign cars !l
 
famous bob said:
looks as good as mine! my fans are staggard up and down, the lower one hangs over the edge of the rad. and shroud on the pass side and the bottom. Had to build the offsets on the outside of the shroud so it would pull air thru the rad. only.
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Actually they're fans I bought here off the forum for 40 bucks shipped. I think they were off a motorhome. LOL
 
trapster said:
So what you are saying is that in a pitch black environment, where color has no effect on anything, something painted black will radiate heat more than something painted white.
I think you are think of surfaces radiating heat from the sun, not surfaces radiating heat from within.
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Exactly. If there is a temperature difference. To experience it, stand behind a window on a col..d black night and you will feel your body heat radiating out to the night sky.
I think the factor for surface color is called emissivity. I am going to check on that.
 
"Painting a radiator black would almost certainly make its performance worse. You have no guarantee it will be any blacker in the far infra-red, and the paint itself would act as a heat insulator degrading the radiators ability to transfer heat to the air."

You saw this part right ?
 
trapster said:
"Painting a radiator black would almost certainly make its performance worse. You have no guarantee it will be any blacker in the far infra-red, and the paint itself would act as a heat insulator degrading the radiators ability to transfer heat to the air."

You saw this part right ?
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Just fo the heck of it, I looked up emissivity factors. For radiant heat transfer, the emissivity of black paint is .97 to .99, while the emissivity of dull aluminum is
.20 to.30 . Big Difference! The emissivity of polished aluminum is only.05 .
I found this info on page 26 of Thermal Environmental Engineering by James K. Threshold. Color is important.
 
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